Quels sont les astres monstrueux + autres faits rares sur l'espace

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Transcript

00:00:00Hang on, dear space enthusiasts, because we are about to discover together the cosmic secrets that have been revealed this year.

00:00:08Giant stars with organic molecules, this year present themselves under the best auspices for astronomers.

00:00:14So, let's catch up everything you may have missed in 2023.

00:00:19To begin with, we have discovered real stellar monsters.

00:00:23Imagine looking up at the night sky to see stars that are not only big, but absolutely huge.

00:00:30Scientists used a top-notch telescope, the James Webb Space Telescope, to explore the first days of the universe.

00:00:39And during their pilgrimage, these researchers came across ancient stars that were 10,000 times larger than our sun.

00:00:47Yes, you heard right, 10,000 times.

00:00:50These giants of the stellar world were among the very first stars to form in the universe several billion years ago.

00:00:58Imagine a globular cluster, like a gigantic cosmic conglomerate, where each group has 100,000 to 1 million members.

00:01:06This cluster is similar to gigantic family reunions.

00:01:10All the stars are born at about the same time.

00:01:13But what makes these recently discovered monsters so special?

00:01:18Well, their cores, in other words their hearts, are much hotter than what we usually observe in stars.

00:01:25Researchers think that this intense heat could be due to the combustion of a large amount of hydrogen at very high temperatures.

00:01:32A bit like a gigantic galactic barbecue.

00:01:35Something fascinating is happening in these globular clusters.

00:01:39The little stars crash into their supermassive neighbors and thus acquire additional energy, a bit like an update.

00:01:46But the hiccup is that most of these clusters are aging, and that these supermassive stars have disappeared for a long time.

00:01:53The clusters we observe today only reveal clues about their existence.

00:01:58Scientists study them from mysterious traces left by their presence.

00:02:03The discovery of these monstrous stars is extremely important for our understanding of the universe.

00:02:09If scientists manage to gather more evidence to confirm their existence, it would be a major step forward.

00:02:17This would allow us to learn more about globular clusters and the formation of supermassive stars in general.

00:02:23But this was only the first fascinating discovery of 2023.

00:02:28The next one is rather sad.

00:02:30You see these beautiful rings that give your Saturn its ravaging look?

00:02:33Well, guess what?

00:02:35They could disappear in the not-so-distant future.

00:02:37Finally, on an astronomical scale.

00:02:39The Cassini mission of NASA, which explored Saturn from 2004 to 2017, allowed us to collect fascinating data on these rings.

00:02:48During the grand final of Cassini's race, during which it made breathtaking maneuvers through the orbit of Saturn,

00:02:56scientists noticed something surprising.

00:02:59The rings lost a lot of their mass every second, tons to be precise.

00:03:04This means that this superb aureole will only remain there for a few hundred million years at most.

00:03:10This may seem long for humans, but on the scale of the universe, it is practically a wink.

00:03:16What must be remembered is that we have discovered that the huge rings, like those of Saturn, do not last forever.

00:03:23They end up disappearing.

00:03:25At least, neither you nor I will be there to witness this moment.

00:03:30Scientists have a funny theory about what will happen when Saturn's rings disappear.

00:03:36They think that the other ice and gas giants of our solar system, such as Uranus and Jupiter, may also have had massive rings.

00:03:45But over time, these rings have crumbled to take on the appearance of thin bands of asteroids, like the one currently owned by Uranus.

00:03:54Saturn's rings are mainly made up of ice, but they are also sprinkled with rocky dust.

00:04:00This comes from asteroids and tiny meteors that crash on other celestial bodies and disintegrate.

00:04:07It's a bit like a storm of icy particles and cosmic debris.

00:04:12Research has also revealed that Saturn's rings appeared long after the formation of the planet itself.

00:04:19They were still forming when dinosaurs populated the Earth.

00:04:23In terms of age, they are therefore quite recent, as they are only a few hundred million years old.

00:04:30This discovery excited astronomers, because it means that a large-scale event occurred in the past of Saturn to create this amazing icy disk.

00:04:40But this is a mystery that is still waiting to be clarified.

00:04:44Scientists would like to understand.

00:04:48What exactly caused the formation of these rings?

00:04:51And why do they have such a breathtaking structure?

00:04:54Let's hope they succeed.

00:04:56But let's move on to something more optimistic, because we have another exciting news from space.

00:05:02Recently, scientists studied one of the most distant galaxies in the universe, and they found something amazing there.

00:05:10Organic molecules.

00:05:12The galaxy in question is called SPTO 41847.

00:05:18It is more than 12 billion light-years away from our little blue planet.

00:05:23Can you imagine such a distance?

00:05:25It is the most distant galaxy where complex organic molecules have never been detected.

00:05:30This is why observing this galaxy is like looking at something from the time when the universe was still a baby.

00:05:37We have no idea of its current appearance.

00:05:41The light that reaches us corresponds to what it was when the universe was only one and a half billion years old.

00:05:48Imagine being able to see things that go back so far in the past.

00:05:53What we found there bears a very complicated name.

00:05:56A polycyclic aromatic hydrocarbon molecule.

00:05:59Or more simply a molecule of HAPE.

00:06:01You are probably wondering, but what is this bidule?

00:06:05Well, guess what?

00:06:06We can actually find these molecules right here, on our good old planet.

00:06:11They can be found in things such as car exhaust smoke, or in forest fires.

00:06:17HAPE molecules are made up of carbon atom chains.

00:06:21And this is what they matter to us.

00:06:23They are considered as the basic elements of life.

00:06:26Realize only.

00:06:28The constitutive elements of life, these tiny carbon chains, were discovered in a very distant galaxy.

00:06:35It's like finding a needle in a haystack.

00:06:38Researchers have also discovered that the gas floating in this galaxy was filled with heavy elements.

00:06:43This is not nothing, because it suggests that many stars have succeeded in this galaxy, creating all these amazing elements.

00:06:51This means that this galaxy is potentially rich in many other elements.

00:06:56This discovery opens up a world of possibilities and raises so many exciting questions.

00:07:01How did these molecules form in such a distant galaxy?

00:07:05And since we are looking in the past, what happened to these organic molecules during this period?

00:07:11Were they able to evolve towards life?

00:07:14We are only revealing the surface of incredible things that are still waiting to be discovered.

00:07:19In fact, if all this happens so far, how did the scientists manage to discover such a thing?

00:07:26Well, once again, they had an instrument.

00:07:29The James Webb Space Telescope.

00:07:32This sophisticated machine was recently launched and has the ability to decouple in terms of observing the universe.

00:07:38When the scientists studied this distant galaxy, they encountered a small problem.

00:07:44The light coming from these distant objects was so weak that it was difficult to see or detect.

00:07:51But guess what? They had a brilliant idea to solve this problem.

00:07:56They used what is called the gravitational lens, which is a bit like the magnifying glass of nature.

00:08:02Imagine two perfectly aligned galaxies, as for a photo shoot.

00:08:07The light from the distant galaxy, the one in the background, is heading towards us.

00:08:11But during its journey, it crosses the foreground galaxy, which acts like a giant space lens.

00:08:17What happens next?

00:08:19The gravity of the foreground galaxy curves the light like a magnifying glass, making it even bigger and brighter.

00:08:26It is as if we had a cosmic zoom for our telescopes.

00:08:30This curvature of the light creates a super cool shape, called Einstein's ring.

00:08:36It is a halo or a ring of light surrounding the foreground galaxy.

00:08:41In fact, it is a way for nature to display the extensive S.S. magical power.

00:08:46Thanks to Einstein's magnificent gravitational lens and his magnificent rings,

00:08:51scientists can see objects further away more clearly and learn amazing things about the distant universe.

00:08:58And thanks to all this, they managed to discover the hidden chemical interactions of the first galaxies.

00:09:05Isn't it incredible?

00:09:07Scientists are frankly overwhelmed by this discovery.

00:09:10They did not expect to find such complex organic molecules in such an incredibly distant galaxy.

00:09:17And who knows?

00:09:18This may only be the beginning of a fascinating cosmic epic.

00:09:22So keep your eyes on the stars, dear space explorers.

00:09:27The universe is full of surprises, and who knows what other breathtaking discoveries await us?

00:09:32We can only hope to learn more about it in the future.

00:09:36We could get closer to the discovery of a huge and icy planet beyond Neptune's orbit.

00:09:42And sorry, Pluto, it's still not you.

00:09:45Recently, a map of the universe using data from a Hawaiian telescope

00:09:49eliminated about 78% of the possible emplacements of this mysterious, or H.R. Lee, of space.

00:09:56Some call it Planet 9, while others prefer Planet X.

00:10:01Whatever it is, it has been subject to controversy since its existence was suggested for the first time.

00:10:07And this is mainly due to the fact that no study so far has been able to answer the big question.

00:10:13Does it really exist?

00:10:15If it were to be discovered, Planet 9 would be classified as the fifth largest planet in our solar system,

00:10:21with a mass ten times greater than that of Earth.

00:10:24It is also thought that it would be gaseous, just like Uranus.

00:10:27An initial study of Planet 9, dating from 2016, suggests that this new colossal planet

00:10:33would have an orbit 20 times further from the Sun than Neptune,

00:10:37which is located at about 4.5 billion kilometers.

00:10:41As a result, Planet 9 would take between 10,000 and 20,000 years to accomplish a single orbit around the Sun.

00:10:49If its existence were proven, this still unknown world would dominate a region

00:10:53larger than any other known planet in our cosmic neighborhood.

00:10:58All these hypotheses are very intriguing, but without the slightest proof or observation allowing them to be substantiated.

00:11:04Before rejecting them as simple crazy assumptions,

00:11:07it is important to note that researchers have relied on complex mathematical models

00:11:12and computer simulations to speculate on the characteristics of this planet.

00:11:17Because that's what scientists do.

00:11:19The existence of this hypothetical planet would explain various mysterious interactions observed beyond Neptune.

00:11:25We are specifically talking about the Quaper Belt,

00:11:28a huge ring-shaped region filled with ice debris dating from the formation of the solar system,

00:11:34including comets and planets such as Pluto.

00:11:37What happens is that the six furthest objects in the Quaper Belt

00:11:43present elliptical orbits, which are all oriented in a similar direction to the physical space

00:11:49and tilted about 30 degrees down compared to the orbital plane of our eight known planets.

00:11:55What is not unusual is that despite the distinct orbital speeds around the Sun,

00:12:00they still have this alignment.

00:12:03The probability that such a concordance occurs by chance is extremely low, around 0.007%.

00:12:11Thus comes the theory of the New Planet,

00:12:13a massive hypothetical celestial body that offers a plausible explanation for this strange phenomenon,

00:12:19by potentially exercising a gravitational attraction that shapes its orbits.

00:12:25The initial theory did not go far in the face of accusations of observation bias and miscalculation.

00:12:31Then, in 2017, another study emerged,

00:12:34reviving the idea that perhaps, after all, the New Planet would be well there somewhere.

00:12:39This time, Spanish astronomers tried an innovative approach.

00:12:43By focusing on the observation of extreme trans-Neptunian objects,

00:12:47these celestial bodies orbit around the Sun in very elongated elliptical trajectories,

00:12:52with average distances exceeding 22 billion kilometers.

00:12:56Their research suggests that the distance between the orbital nodes of these objects and the Sun

00:13:01could provide us with clues about the location of the New Planet.

00:13:05See, these nodes are the points where the orbit of a celestial body intersects the plane of the solar system.

00:13:10When these objects reach such a point,

00:13:13they are more likely to interact with other celestial bodies of the system,

00:13:17which can then cause significant changes in their orbits, or even collisions.

00:13:22So, if the trajectory of these extreme trans-Neptunian objects remains stable, everything is fine.

00:13:28But if this is not the case, well, it is a sign that something else, something big, disturbs their orbit.

00:13:34And that's exactly what this study has discovered.

00:13:37There is something invisible there, which diverts these objects from their path,

00:13:41and this something could be a planet three to four hundred times farther from the Sun than the Earth.

00:13:47To this day, the study of extreme trans-Neptunian objects

00:13:51is the most tangible proof that we have of the existence of the New Planet.

00:13:55And if you are still not convinced by this theory,

00:13:58know that strange movements like this have already led to the discovery of planets in the past.

00:14:04Neptune, for example, was spotted because the movement of Uranus

00:14:08did not quite correspond to the predictions of Newtonian gravity.

00:14:11But this deviation of its orbit could be explained if it was caused by the attraction of an unknown planet.

00:14:18And that's how we discovered Neptune.

00:14:22Let's move on to 2021.

00:14:25And the debate persists around the mysterious New Planet.

00:14:28After having revised some old assumptions,

00:14:31studies are now looking for the idea that this planet would accomplish a revolution around the Sun every 7,000 years.

00:14:37It's a big news.

00:14:39Because that means that this planet could be closer than we thought,

00:14:43which would facilitate its detection by our telescopes.

00:14:46The study also suggests that there is a 99% chance

00:14:50that the orbits shifted from these distant objects are all due to this invisible planet,

00:14:55and not to a simple cosmic coincidence.

00:14:58At present, the chances that this whole anomaly is only random

00:15:02are reduced to 1 in 250,

00:15:05which is much better than a chance of 10,000, as in 2016.

00:15:11All these optimistic figures have brought us where we are today.

00:15:15To keep hope and develop better equipment to pursue the quest for the New Planet.

00:15:20As mentioned earlier, researchers in Hawaii have created a kind of treasure map,

00:15:26using the panoramic survey telescope and its rapid response system

00:15:31to eliminate 78% of its possible locations.

00:15:35It's very good news,

00:15:38given the difficulty of finding a planetary needle in a cosmic haystack.

00:15:44But unfortunately, the New Planet remains unreachable

00:15:47in the dark confines of our solar system.

00:15:50Enthusiasts are still convinced of its existence,

00:15:53and think that it is only a matter of time before we celebrate the discovery of a new neighbor.

00:15:58They are hoping for the Vera C. Rubin Observatory,

00:16:02which is currently under construction in Chile,

00:16:05which should be fully operational by the end of 2025.

00:16:09Over the next 10 years, this observatory will sweep the entire sky of the southern hemisphere

00:16:14every few nights with an 8-meter telescope,

00:16:17equipped with the largest digital camera in the world.

00:16:20The idea is to catalog the entire solar system, beyond Neptune,

00:16:24and track the movements of millions of celestial objects,

00:16:27including space debris, asteroids, comets and other stars.

00:16:32If the New Planet is actually there,

00:16:35this new generation telescope could be the one to achieve it.

00:16:42The existence of this mysterious planet is far from being accepted by the entire scientific community.

00:16:47It is simply because the New Planet is not the only explanation

00:16:50for the strange phenomena that occur on the part of Neptune.

00:16:53A theory suggests that a group of distant objects,

00:16:56such as dwarf planets, comets or moons,

00:16:59could collectively influence the orbits of extreme trans-Neptunian objects.

00:17:03Others believe that a black hole would be at the origin of all this.

00:17:07These ultra-compressed masses are among the densest objects in the universe,

00:17:11potentially capable of affecting the orbits of other objects,

00:17:15as is supposed for this ghostly New Planet.

00:17:21Another bold theory suggests that our current understanding of the laws of gravity

00:17:26would be wrong, or rather incomplete.

00:17:29The latter, known as modified Newtonian dynamics,

00:17:32suggests that these distant frozen objects exhibit this strange behavior

00:17:36not because of the interference of another planet,

00:17:39but rather because the immense gravitational field of the Milky Way influences them.

00:17:44However, even supporters of this theory recognize that it is too early

00:17:48to draw definitive conclusions.

00:17:51And much more in-depth research is still necessary.

00:17:56As we continue our track of the New Planet,

00:17:59some astronomers have gone even further,

00:18:02suggesting the existence of a hypothetical planet of X.

00:18:05It would have a mass and a size similar to that of Mars or Earth,

00:18:09and would be at the edge of Kuiper Belt.

00:18:13But here's the thing.

00:18:15If this supposed planet of X is actually as small as scientists think,

00:18:20it could not have enough gravity to clear its orbit of the surrounding debris.

00:18:25And it's quite similar to what's going on with Pluto.

00:18:28This is one of the reasons why it was retrograded in 2006.

00:18:33So, indeed, it's better not to get too carried away.

00:18:37This supposed planet of X could end up being classified as another dwarf planet.

00:18:42The Earth is not flat, but Jupiter could have been.

00:18:46Jupiter is one of our oldest neighbors.

00:18:49It is 4.6 billion years old, just like our Sun.

00:18:52And when it was still young, it probably formed in a protoplanetary disk.

00:18:57It all starts with the stars.

00:19:00When a star is still forming, it does not look like a round object.

00:19:04It's more like a large disk of matter.

00:19:07At this stage, hot winds blow from the north to the south.

00:19:11At this stage, hot winds blow from the north to the south.

00:19:15At this stage, hot winds blow from the north to the south.

00:19:18The dust of this disk contains elements like carbon and iron.

00:19:22Some of them collide and remain together, forming larger objects.

00:19:27The dust turns into pebbles, the pebbles turn into rocks,

00:19:32and the rocks hit each other, becoming larger and larger.

00:19:36The gas in the disk helps all these solid pieces to agglutinate.

00:19:40Some of them detach, but others remain together,

00:19:43and they become the basis of the planets.

00:19:46They are called planetesimals.

00:19:48Even gas giants like Jupiter began as tiny particles of dust,

00:19:54smaller than a human hair.

00:19:56Finally, they formed their own disk of matter.

00:20:00Then they began to rotate around our Sun,

00:20:03growing as they accumulated gas and rocks like a big ball of snow.

00:20:10Gas giants are special.

00:20:13They are born from the coldest parts of the disk.

00:20:16In these cold regions, the molecules are slower,

00:20:19making them easier to capture.

00:20:22The water can freeze, and tiny pieces of ice stick together

00:20:26and mix with the dust.

00:20:28These balls of salty snow then form the cores of vast planets

00:20:33like Jupiter, Saturn, Uranus and Neptune.

00:20:37In the warmer regions, close to the star,

00:20:40telluric planets like Mercury, Venus, Earth and Mars begin to form.

00:20:46After the birth of ice giants,

00:20:48there was not much gas left for these tiny celestial bodies,

00:20:51and it could take tens of millions of years

00:20:54for such planets to form after the birth of a star.

00:20:57Our Sun was growing at the same time,

00:21:00sucking in the gas close and pushing the distant objects even further.

00:21:04After billions of years, the disk has completely changed,

00:21:07turning into a spherical star with a bunch of giant and tiny planets,

00:21:12asteroids, moons, meteorites and comets around it.

00:21:20Recently, simulations have shown that these proto-planets,

00:21:23as we call these first dust conglomerates,

00:21:26did not start by looking like the planets we know.

00:21:30In the case of gas giants like Jupiter,

00:21:32they would look more like crushed balls or M&Ms.

00:21:37When the Sun was still young,

00:21:39the gas and dust disk surrounding it cooled down and became unstable.

00:21:44It began to break into large pieces.

00:21:47These gathered under the effect of an implacable gravity to create Jupiter.

00:21:52Then it became a spherical gas giant over time.

00:21:56Quantities of anomalies can occur during this process of planet formation.

00:22:00Have you ever wondered why Venus or Uranus rotate in the opposite direction?

00:22:05Usually, when things are formed from a rotating gas disk,

00:22:09they tend to rotate in the same direction.

00:22:12If you rotate a bunch of balls tied to a string, for example,

00:22:16they will all rotate in the same way.

00:22:18So, theoretically, all the planets should also rotate in the same direction.

00:22:24But there are also many objects that move quickly in our solar system,

00:22:28such as comets and asteroids.

00:22:30When they collide with the planets, especially during their first days,

00:22:34this impact can lead them to rotate in the opposite direction.

00:22:38Venus and Uranus have probably survived a large-scale collision.

00:22:42Fortunately, they were not ejected into space.

00:22:45The gravity of the Sun and neighboring planets kept them in their place.

00:22:53There are also what are called gravitationally locked planets.

00:22:57They are celestial bodies that rotate so that one side is always facing their star,

00:23:03while the other remains in perpetual darkness.

00:23:06Thus, one side is always very hot, while the other is extremely cold.

00:23:10If we lived on such a planet, we could only exist on a thin band between these two extremes.

00:23:16These planets are formed when they are very close to their star.

00:23:20The gravitational forces at work are intense and, over time,

00:23:24slow down the rotation of the planet until it corresponds to the time it takes to orbit around its star.

00:23:31Imagine that you are turning on your chair.

00:23:34Someone approaches you and, holding your chair in his hands, starts to turn with you.

00:23:39In this way, you will face each other all the time.

00:23:42Synchronous rotation planets work a little like this.

00:23:45Our Moon is also in synchronous rotation with the Earth.

00:23:49That's why we only see one side of it.

00:23:54We have discovered more than 5,000 exoplanets outside our solar system.

00:23:59Some of them have very strange orbits.

00:24:02There are some, for example, that have incredibly long orbits,

00:24:06thousands of years to make a single revolution around their star.

00:24:10Or very unequal orbits, similar to those of comets.

00:24:14Or those planets that are called hot Jupiters,

00:24:17which are very close to their star, much closer than Mercury is to our Sun.

00:24:21But these planets could not have formed where they are now.

00:24:25As their solar system evolved, they, for one reason or another, changed position.

00:24:31This rearrangement is called planetary migration.

00:24:37There are three ways this migration can occur.

00:24:40First, due to the gas and dust in rotation around the planet.

00:24:45When a planet collides with this matter,

00:24:49it can create spiral patterns in the gas.

00:24:52These patterns can either bring the planet closer to the center,

00:24:55or move it away, depending on how they mix.

00:24:58This is called a type I migration.

00:25:01This is what Jupiter experienced when it got closer to the Sun billions of years ago.

00:25:06And this also explains the existence of hot Jupiters.

00:25:10Secondly, large planets can move smaller ones, changing their trajectory.

00:25:15And thirdly, the gravity of the star can attract the planet, making its orbit circular.

00:25:24Have you ever heard of wandering planets?

00:25:27Imagine a lonely planet, floating in the vastness of space,

00:25:31without being attached to any star.

00:25:34These are the wandering nomads of our galaxy, condemned to wander eternally.

00:25:38And there are so many of them.

00:25:40There could be more planets in freedom than planets linked to a star.

00:25:44We are talking about thousands of billions of wandering bodies in our Milky Way.

00:25:50It is not uncommon for them to be as massive as our largest planet, Jupiter.

00:25:55But most of them would have a size more comparable to that of the Earth.

00:25:59There are even some that could have a thick atmosphere capable of keeping them warm.

00:26:04Although they are the eyes of every star,

00:26:06some of these planets may have horrors to cut the breath,

00:26:09while others may be entourages of moons containing liquid air,

00:26:13a potential havoc for life.

00:26:15There is even a chance that they may inhabit an extraterrestrial life.

00:26:19These planets could be hit by other stars,

00:26:21or even entire planetary systems, during their crazy races through space.

00:26:25Sometimes they can be captured by the gravity of a star for a certain time,

00:26:30before being ejected back into space.

00:26:33But how are they born?

00:26:34Sometimes, during this chaotic formation process,

00:26:37all the planets fail to stay close to their related stars.

00:26:41Some of them are expelled from their solar system,

00:26:44due to the powerful gravitational attraction of other planets,

00:26:48or passing stars.

00:26:50These ejected planets then become wandering planets.

00:26:57In 2012, astronomers discovered a solar system dating from the beginning of the universe.

00:27:02This system includes a star and two planets.

00:27:05It was nicknamed the Fossil System.

00:27:08Its star is incredibly old,

00:27:11about 13 billion years old,

00:27:13almost as old as our universe itself.

00:27:16This system is mainly composed of hydrogen and helium.

00:27:20This is unusual, because planets are generally formed from gas clouds

00:27:25containing heavier elements.

00:27:27It was then that we understood that the way planets were formed before

00:27:31was different from the way they are formed today.

00:27:34We know that the stars containing the most metals

00:27:37are the most likely to have planets.

00:27:40In astronomical language,

00:27:41metal means any chemical element other than hydrogen and helium.

00:27:46But in the primitive universe, there were not many heavy elements.

00:27:50Most of them were created inside the stars,

00:27:54and then dispersed in space when they exploded.

00:27:58So, when did the very first planets form?

00:28:02This newly discovered system helps to answer this question.

00:28:05These two giant planets are orbiting around a star,

00:28:08which is incredibly poor in metals and extremely old.

00:28:12This should be very rare, even impossible,

00:28:15but they exist, yet.

00:28:17This may mean that there are more planets in poor metal systems

00:28:21than we thought.

00:28:23Students will help us learn more about the formation of planets.

00:28:28The sun is about to turn around

00:28:30because its magnetic poles are inverting.

00:28:32Just like the Earth, the sun has a magnetic north and a magnetic south.

00:28:36However, unlike our planet,

00:28:38the process of inversion of the poles of the sun is more frequent

00:28:42and easier to predict.

00:28:44The next reversal is expected this year between April and August.

00:28:48As apocalyptic as it may seem,

00:28:50you don't have to worry.

00:28:52If you are about 30 years old,

00:28:54you have already experienced this phenomenon more than once,

00:28:56because the sun turns around every 11 years.

00:28:59You probably didn't notice any changes at the time,

00:29:02because this process has no major impact on terrestrial life.

00:29:06But this time, things could be a little different.

00:29:10On Earth, sea currents are movements that play a crucial role

00:29:14by influencing the climate and the weather

00:29:16and by distributing the heat of the equator to the poles.

00:29:19In the sun, these currents are more like a plasma ocean.

00:29:23But they do not only transport heat,

00:29:26they also transport electromagnetic energy.

00:29:29This happens because the sun is a huge ball of incandescent and ionized gas

00:29:34that continues to circulate inside its nucleus.

00:29:37By fusing these hydrogen atoms to form helium,

00:29:40our star releases a huge amount of energy

00:29:43producing these powerful electric currents.

00:29:46And every time you have such currents,

00:29:48you have magnetic fields.

00:29:50It's easier to visualize if you think back to this classic experiment

00:29:54with a copper wire and a nail that you probably made at school.

00:29:58When an electric current passes through a wire,

00:30:01it creates a magnetic field around it.

00:30:04So when you connect a wire to a battery and wrap it around a nail,

00:30:08this nail becomes magnetized.

00:30:10It's similar to the way electric currents

00:30:13generate magnetic fields around the sun.

00:30:17All of this process,

00:30:19thanks to which the sun generates its magnetic field,

00:30:22is what we call a dynamo.

00:30:24We cannot observe it directly,

00:30:26but we can see the effects on the surface of the sun.

00:30:29When plasma and magnetic flows become unstable,

00:30:32they manifest in the form of solar splashes.

00:30:36You know, those dark areas on the surface of the sun.

00:30:39We still don't know a lot about how this dynamo works,

00:30:42but scientists have understood something important

00:30:45after observing these solar splashes over the centuries.

00:30:48This process follows a certain pattern.

00:30:51About every decade, it reorganizes itself.

00:30:54The magnetic fields of the poles of the sun

00:30:57diminish until they completely disappear,

00:30:59then they return, but with an opposite polarity.

00:31:02In the 1950s, researchers discovered

00:31:05that when the solar splashes began to intensify,

00:31:08it meant that the poles were preparing for an inversion.

00:31:12But in recent years, solar activity has been out of the ordinary.

00:31:16More solar eruptions,

00:31:18electromagnetic radiation bursts,

00:31:20and more plasma ejections into space.

00:31:23It's as if we were sitting in the first row

00:31:25of the largest pyrotechnic show of the solar system.

00:31:28In fact, the sun has probably not been so animated

00:31:31over the last two decades.

00:31:33At present, experts believe that the magnetic fields of the poles

00:31:37are almost synchronous and are weakening little by little,

00:31:41getting closer and closer to zero.

00:31:43But we have not yet reached the point of inversion.

00:31:48Although it may seem that the sun reverses its poles every 11 years,

00:31:51like a clock,

00:31:52the truth is that it is not so clearly defined.

00:31:55This path is not made without obstacles,

00:31:57and some aspects of the phenomenon are still very difficult to predict.

00:32:01Take the last solar cycle, for example.

00:32:03The northern hemisphere began its magnetic inversion

00:32:06as early as June 2012,

00:32:08but then encountered an obstacle

00:32:10and stagnated around the neutral point until the end of 2014.

00:32:13During this time, in the southern hemisphere,

00:32:15things became more fluid,

00:32:17and the change in polarity occurred in 2013.

00:32:20This time, solar activity seems more regular.

00:32:23Things seem to unfold more smoothly during this cycle,

00:32:27with a more uniform transition of poles.

00:32:29But here's the thing,

00:32:30this inversion process never repeats itself,

00:32:33and that's what makes this phenomenon so interesting to observe.

00:32:37But at the same time,

00:32:38it is difficult to predict how this will affect us down here.

00:32:43Here on Earth,

00:32:44we have no war to worry about these intense solar explosions,

00:32:47which occur at 150 million kilometers away.

00:32:51But if, and we say well if,

00:32:53a solar storm were to hit our planet,

00:32:56the main threat it would pose

00:32:58would probably be the disturbance of communication satellites in space.

00:33:02Nevertheless,

00:33:03things could take a different turn

00:33:05during the planned inversion cycle for 2024,

00:33:07because the number of satellites in orbit has exploded in recent years.

00:33:11The Starlink system, for example,

00:33:13involves alone more than 4,000 of them.

00:33:16All these communication satellites and other GPS

00:33:19could be impacted, or even destroyed,

00:33:22by a powerful solar storm.

00:33:26Although the chances of a powerful solar storm hitting Earth are slim,

00:33:30it is not impossible.

00:33:31In 1859, during the Carrington event,

00:33:34a storm occurred near a peak of solar activity,

00:33:37causing overvoltages in the telegraphic lines,

00:33:40triggering fires,

00:33:41and disrupting world-scale exchanges.

00:33:44The Earth was silent

00:33:46when all these telegraphic communications were cut off.

00:33:49Just imagine what a solar storm

00:33:51could do to our vast fleet of satellites today.

00:33:54It could affect everything we rely on daily,

00:33:57from geolocation and telecommunications

00:34:00based in space to weather forecast services.

00:34:03Electricity distribution on the ground

00:34:06could also be affected.

00:34:08You can make a cross on YouTube,

00:34:10and even nice,

00:34:11because if such an event occurred today,

00:34:13it could put the Internet to bad use,

00:34:15cutting off countless people from the world.

00:34:18Predictions say that if a Carrington-type event

00:34:21occurred today,

00:34:22it would result in damage

00:34:24amounting to 600 to 2,600 billion dollars.

00:34:27And we are talking here only about the United States.

00:34:30Fortunately for us,

00:34:31storms as intense as the Carrington event

00:34:34only occur once every 500 years or so.

00:34:40Bad news for telecommunications satellites,

00:34:42but excellent news for observers of aurora borealis.

00:34:46During the Carrington event,

00:34:47dazzling auroras illuminated the sky,

00:34:50and the spectacle of polar lights

00:34:52spread far beyond ordinary countries.

00:34:54These aurora borealis were seen

00:34:56as far south as Cuba and Honolulu,

00:34:59while australian auroras were seen

00:35:01as far south as Santiago, Chile.

00:35:03For many people around the world,

00:35:05this was their first sight of such auroras,

00:35:08leaving them stunned in front of these unusually bright skies.

00:35:11Some then thought it was the end of the world,

00:35:14while others woke up unusually early,

00:35:17believing that the sun had risen

00:35:19after hearing the birds chirping and all this light.

00:35:22Today, we know that there is nothing strange about this,

00:35:25given that the appearance of auroras at such latitudes

00:35:28is one of the expected effects of the inversion of the magnetic poles of the sun.

00:35:31Typically, these iridescent phenomena

00:35:34are observed between 60 and 75 degrees of latitude,

00:35:37but during the last inversion of the magnetic poles,

00:35:40in 2013,

00:35:42intense auroras were observed below 50 degrees.

00:35:46Witnesses have described these auroras as being

00:35:49red-blooded, shooting on the sky,

00:35:52and shining so brightly that one could read a newspaper in their own light.

00:35:57It is important to study this phenomenon,

00:35:59rather than fearing it.

00:36:01The inversion of the magnetic poles of the sun

00:36:03is actually a perfect opportunity for scientists

00:36:05to better understand how our star works.

00:36:08And as there are still many pieces of the puzzle

00:36:10that is solar dynamo,

00:36:12we are still not able to understand

00:36:14why some cycles are more intense than others,

00:36:17or to predict when an ejection of coronal mass will occur exactly.

00:36:21But being able to predict them

00:36:23becomes more and more crucial

00:36:25as we venture into space.

00:36:27The more people are in orbit around the Earth,

00:36:30the more they are exposed to these strong solar storms.

00:36:33This is why the scientific community

00:36:35seeks to learn more precisely

00:36:37when such a storm could cause damage

00:36:39to our ships and our space stations.

00:36:42In addition, this would help meteorologists

00:36:44to make better predictions,

00:36:46not only on Earth,

00:36:48but also in space.

00:36:50The main goal would be to make space travel safer

00:36:53as our interest in missions

00:36:55inhabited by the Moon and Mars

00:36:57continues to grow.

00:36:58Another reason why it would be important

00:37:00to learn more about the inversion of the poles of the sun

00:37:03and to better understand

00:37:05how the mysterious heart of our star works.

00:37:08This could indeed help us

00:37:10grasp the aspect of other stars in the universe

00:37:12and perhaps bring us closer to the answer

00:37:14to the ultimate question.

00:37:16What are we doing here?

00:37:19If you want to travel in space,

00:37:21prepare to spend about 55 million dollars.

00:37:25But in the near future,

00:37:27you could probably travel in space

00:37:29by simply pressing a button without ruining yourself.

00:37:32Because space elevators

00:37:34could come into play.

00:37:36While the idea of a galactic elevator

00:37:38seems to come from a science fiction movie,

00:37:40it is a real possibility

00:37:42that could revolutionize space travel.

00:37:44With an estimated cost of 8 billion dollars,

00:37:47such an elevator could represent

00:37:49only a single investment

00:37:51that would last us forever.

00:37:55NASA alone

00:37:57spends about 2,700,000 dollars

00:37:59on rocket fuel

00:38:01every minute of flight.

00:38:03To launch a rocket,

00:38:05it would cost up to 178 million dollars.

00:38:07These costs could be considerably reduced

00:38:09if we used elevators.

00:38:11Most of the tallest buildings on Earth

00:38:13have massive foundations

00:38:15to help balance their weight.

00:38:17The more you look in the air,

00:38:19the more they shrink.

00:38:21Even the highest skyscraper in the world,

00:38:23the Burj Khalifa,

00:38:25is thick at its base

00:38:27and thin at its top.

00:38:29If we wanted to build something

00:38:31that looks like a gigantic elevator,

00:38:33we would need a huge amount of concrete

00:38:35to build the foundations,

00:38:37which goes against

00:38:39our original goal

00:38:41of saving money.

00:38:43Now, take a string,

00:38:45attach a ball to its end

00:38:47and start spinning it.

00:38:49The string in your hand will stay in place

00:38:51and the ball will spin around your hand.

00:38:53This is called centrifugal force.

00:38:55And the elevator will work the same way.

00:38:57The ball will be a base in space

00:38:59and the rope will pull towards the ground.

00:39:03The station

00:39:05through which we would enter

00:39:07in the elevator would be

00:39:09in the middle of the Atlantic Ocean

00:39:11and the cable would extend from there.

00:39:13For this to be possible,

00:39:15it must be perfectly synchronized

00:39:17with the rotation of the Earth.

00:39:19Otherwise, it will simply break

00:39:21or roll around the Earth

00:39:23like a whip.

00:39:25In addition, the orbit followed by the cable

00:39:27should form a perfect circle

00:39:29because the line could neither shorten

00:39:31nor extend.

00:39:33Many calculations have been made

00:39:35in order to find the ideal solution.

00:39:37Wait a minute.

00:39:39So that's what algebra is for.

00:39:41Who would have thought?

00:39:43In the meantime, we will not bother you

00:39:45with more math.

00:39:47Let's address directly the precise distance

00:39:49between the Atlantic Station

00:39:51and the one in space,

00:39:53which must be 36,000 km above the Earth,

00:39:55where the geosynchronous orbit begins.

00:39:57There,

00:39:59the four ascending forces

00:40:01are much stronger than the only descending force.

00:40:03This is why the station

00:40:05would remain in place.

00:40:07When you build a house

00:40:09or a building, you start from the bottom

00:40:11and progress upwards.

00:40:13But to create this marvel of engineering,

00:40:15we would need to go

00:40:17backwards and start from the top.

00:40:19The main problem

00:40:21here would be the weight.

00:40:23If the line was too heavy,

00:40:25it would disturb the orbit

00:40:27and the load would not work.

00:40:29We would therefore need

00:40:31to balance the space station

00:40:33to ensure flawless operation.

00:40:37Steel is one of the

00:40:39most robust materials on Earth.

00:40:41The cable of each elevator

00:40:43is made of steel.

00:40:45But when you need a cable

00:40:4736,000 km long,

00:40:49things can get a little complicated.

00:40:51Steel is difficult to break,

00:40:53but it is bulky

00:40:55and when you have to use

00:40:57a lot of it,

00:40:59problems start to arise.

00:41:01We use a lot of steel

00:41:03in construction,

00:41:05but we have lighter materials

00:41:07at our disposal

00:41:09which could exert less

00:41:11strain on the station

00:41:13and eliminate this problem.

00:41:15In addition, the cable should be

00:41:17fused because at the end

00:41:19the constraint would be

00:41:21practically non-existent.

00:41:23At the beginning,

00:41:25the cable would be barely

00:41:27more than 1 mm thick.

00:41:29After a lot of complicated calculations,

00:41:31we can determine its size

00:41:33at the end of the race,

00:41:35which represents such a long number

00:41:37that we would be unable

00:41:39to pronounce it.

00:41:41But believe us,

00:41:43it is a very, very large number.

00:41:45So steel is out of the question.

00:41:47Another candidate is Kevlar,

00:41:49which is 5 times more resistant

00:41:51than steel.

00:41:53The cable would then have

00:41:55a diameter between 80 and 170 m.

00:41:57It is much smaller

00:41:59than the diameter

00:42:01of such a steel cable.

00:42:03The bad news is

00:42:05that it would cost too much.

00:42:07So if we do not find

00:42:09the ideal material to build

00:42:11this cable,

00:42:13the very idea of a space elevator

00:42:15will never be a vast waste of time.

00:42:18If only we had

00:42:20a light, miraculous material

00:42:22capable of absorbing

00:42:24a pressure of 60 gigapascals,

00:42:26and which would also have

00:42:28a conicity ratio of 1.6.

00:42:30Oh, but wait,

00:42:32we do have such a material.

00:42:34These are called

00:42:36carbon nanotubes.

00:42:38They have a resistance of 130 gigapascals,

00:42:40which is much more

00:42:42than what we need.

00:42:44Nanotubes are made

00:42:46from carbon,

00:42:48and are 100,000 times thinner

00:42:50than human hair.

00:42:52This material is solid

00:42:54and has a good conductivity,

00:42:56which is made possible

00:42:58thanks to its unique

00:43:00atomic structure.

00:43:02We use this innovation

00:43:04in many things,

00:43:06from batteries to optics,

00:43:08and they can be

00:43:10entirely modified

00:43:12and adapted

00:43:14to our needs.

00:43:16The idea of a

00:43:18nanotube is

00:43:20a very simple one.

00:43:22It is a very simple

00:43:24and very powerful

00:43:26device.

00:43:28It is a very simple

00:43:30and very powerful

00:43:32device.

00:43:34It is a very simple

00:43:36and very powerful

00:43:38device.

00:43:40It is a very simple

00:43:42and very powerful

00:43:44device.

00:43:46It is a very simple

00:43:48and very powerful

00:43:50device.

00:43:52It is a very simple

00:43:54and very powerful

00:43:56device.

00:43:58It is a very simple

00:44:00and very powerful

00:44:02device.

00:44:04It is a very simple

00:44:06and very powerful

00:44:08device.

00:44:10Hey, are you looking for an escape atmosphere?

00:44:12Well, don't come here,

00:44:14we don't have any.

00:44:16Oops, probably not the best

00:44:18advertising slogan, is it?

00:44:20A few years ago,

00:44:22we could only create nanotubes

00:44:24of microscopic carbon, but

00:44:26over time, more research has been

00:44:28carried out to make them larger.

00:44:30Today, they reach a few

00:44:32centimeters. In 20 years,

00:44:34they could be several kilometers

00:44:36long. Carbon

00:44:38costs $ 1 per gram.

00:44:40If we did the math, we would see that

00:44:42it would take us about $ 1 billion

00:44:44to build this elevator.

00:44:46Yes, it seems expensive, but it is a

00:44:48long-term solution for space travel

00:44:50that could save us a lot

00:44:52of money. Everything

00:44:54looks perfect on paper.

00:44:56But the main reason why NASA

00:44:58chose not to pursue this project

00:45:00is that at present,

00:45:02there are probably more than 128

00:45:04million debris floating in the Earth's orbit,

00:45:06and they could pose a real

00:45:08threat to this elevator.

00:45:10It could, of course,

00:45:12be designed to resist

00:45:14a few impacts from time to time,

00:45:16but being constantly bombed

00:45:18was not part of the equation.

00:45:20Nevertheless, Bradley argues that an armada

00:45:22of surveillance devices detects these

00:45:24spatial debris. Thus,

00:45:26the elevator could be able to

00:45:28avoid them all.

00:45:30If something hit the elevator,

00:45:32or if the cable

00:45:34broke in one way or another,

00:45:36the consequences would not be too severe.

00:45:38Finally, if there were no passengers

00:45:40on board, of course.

00:45:42If the line was cut,

00:45:44the elevator would simply drift into space

00:45:46and would not pose any threat

00:45:48to anyone. In Japan,

00:45:50engineers are trying to build

00:45:52a space elevator.

00:45:54This one could also be

00:45:56used for mining in space.

00:45:58We could easily

00:46:00cover the cost of this elevator

00:46:02by catching asteroids in the process,

00:46:04because some of them are made of precious metals.

00:46:06We could then exploit them

00:46:08and repatriate them quickly on Earth.

00:46:14If one of the many

00:46:16possible apocalyptic scenarios comes true

00:46:18and humanity is eradicated,

00:46:20a black box

00:46:22will tell those who will come

00:46:24after what led us to our end.

00:46:26This strong room

00:46:2810 meters long located in a

00:46:30remote region of western Tasmania

00:46:32is supposed to document all the mistakes

00:46:34humanity has made and

00:46:36which caused the apocalypse.

00:46:38Artists, architects

00:46:40and researchers at the origin of the

00:46:42black box on Earth

00:46:44think that this reinforced steel installation

00:46:46will resist fire, water

00:46:48and all other natural disasters.

00:46:50Unless, of course,

00:46:52the planet is completely destroyed.

00:46:56Just like the black boxes

00:46:58on airplanes.

00:47:00This time capsule is supposed to help

00:47:02the civilization that will follow ours

00:47:04to avoid the tragic fate of our humanity.

00:47:08The project is entirely non-commercial

00:47:10and carries an important message.

00:47:12The box will be filled with

00:47:14storage disks and will be connected

00:47:16to the Internet.

00:47:18Solar panels on the roof will feed it

00:47:20with electricity and batteries

00:47:22will ensure the storage of emergency energy.

00:47:24Every time the sun shines in the sky,

00:47:26the black box will update

00:47:28its scientific data.

00:47:30An algorithm will sort these data

00:47:32in order to save only the relevant information

00:47:34for the project.

00:47:36We will measure the terrestrial and marine temperatures,

00:47:38the acidification of the oceans,

00:47:40the extinction of species,

00:47:42the use of land as well as

00:47:44human demography and energy consumption.

00:47:46Among the secondary data,

00:47:48we will find newspaper titles,

00:47:50social network posts and news

00:47:52on the main events

00:47:54of the project.

00:47:56The creators of the box decided

00:47:58to code and store their data

00:48:00in different formats,

00:48:02including binary code.

00:48:04Instructions on how to retrieve

00:48:06all this precious information

00:48:08will be engraved on the outside of the box.

00:48:12Some of the greatest brains

00:48:14working on this project fear

00:48:16that this may make some curious people

00:48:18want to force the box long before

00:48:20it's time to do it.

00:48:22A hard disk powered by solar energy

00:48:24will have enough space to

00:48:26collect data for 50 years.

00:48:28The most pessimistic scientific models

00:48:30do not predict the end of the world

00:48:32before this date.

00:48:34This great misfortune may not even happen

00:48:36in centuries.

00:48:38The idea of a box

00:48:40that records everything that happens

00:48:42before an aviation accident

00:48:44was born in the middle of the 20th century.

00:48:48At that time, the world's first

00:48:50aviation company,

00:48:52the De Havilland's Comet,

00:48:54crashed seven times in two years,

00:48:56killing 110 people.

00:49:00The Australian Department of Civil Aviation

00:49:02wanted to know what caused these accidents.

00:49:06Among the experts,

00:49:08there was Dr. David Warren,

00:49:10a chemist specializing in fuels.

00:49:12He realized that we simply

00:49:14didn't have enough data

00:49:16to draw conclusions.

00:49:18To tell what had happened

00:49:20before the accident,

00:49:22he remembered seeing a recorder

00:49:24recording sound on a steel wire

00:49:26at a commercial fair.

00:49:28So, he wrote to his superior

00:49:30to propose him to design

00:49:32a voice recorder

00:49:34that would follow what was happening

00:49:36in the cockpit.

00:49:38Flight data would also be recorded

00:49:40and stored in an unbreakable box.

00:49:42Aviation was not very important

00:49:44in Australia at that time,

00:49:46but Warren still began

00:49:48to work on a prototype

00:49:50in his garage.

00:49:52He showed his device

00:49:54to the British Air Registration Board

00:49:56secretary,

00:49:58and he loved the idea.

00:50:00Soon, Dr. Warren

00:50:02was able to form a whole team

00:50:04to help him develop a pre-production prototype.

00:50:08His invention does not actually

00:50:10have the name of a black box,

00:50:12but of a flight recorder,

00:50:14orange, not black.

00:50:16We probably say

00:50:18that it is black because it takes

00:50:20this color after an accident.

00:50:22Or maybe because the first boxes

00:50:24were painted like that

00:50:26to avoid solar reflection.

00:50:28Or because it is the name

00:50:30that scientists give to devices

00:50:32with input and output data

00:50:34and complex internal operation.

00:50:36So, the flight recorder

00:50:38consists of two parts,

00:50:40a data recorder

00:50:42and a vocal recorder.

00:50:44Historically,

00:50:46it was two boxes,

00:50:48but now it is two cylinders.

00:50:50The data recorder

00:50:52keeps the flight parameters,

00:50:54the exhaust gases,

00:50:56the temperature,

00:50:58the fuel flow,

00:51:00the speed, the altitude

00:51:02and the descent rate.

00:51:04The second cylinder

00:51:06records the sounds

00:51:08in the cockpit

00:51:10and processes these data.

00:51:12Sometimes,

00:51:14the two parts are combined

00:51:16and it looks like a box.

00:51:18The box records the data

00:51:20and sees them in the cockpit.

00:51:22But it is actually placed

00:51:24at the back of the plane

00:51:26where the structure of the aircraft

00:51:28will protect them in case of an accident.

00:51:30The black box has a locating beacon

00:51:32that is activated when in contact with water.

00:51:34It emits a signal for 30 days.

00:51:36The bright orange color

00:51:38of the recorder

00:51:40allows the search teams

00:51:42to locate it more easily.

00:51:44Sometimes, it takes a lot of time

00:51:46to find a box,

00:51:48and in some cases,

00:51:50it is never found.

00:51:52Long before the invention

00:51:54of the first aircraft,

00:51:56there was a black box

00:51:58with a universal range,

00:52:00the old library of Alexandria.

00:52:02In Antiquity,

00:52:04people in Egypt, Mesopotamia

00:52:06and the Middle East

00:52:08used it to preserve

00:52:10their traditions and heritage.

00:52:12The concept of a universal library

00:52:14became a reality

00:52:16when the Greeks

00:52:18started to think big.

00:52:20They were so impressed

00:52:22by what their neighbors did in Egypt

00:52:24that they organized expeditions

00:52:26to acquire knowledge.

00:52:28Alexander the Great,

00:52:30king of Macedonia,

00:52:32saw this new thirst for knowledge

00:52:34that he brought him

00:52:36everything he could learn

00:52:38about the regions that had not yet been explored.

00:52:40This allowed him to collect

00:52:42a lot of information on geography

00:52:44and contributed to the creation

00:52:46of a huge library.

00:52:48Most of the information

00:52:50was written in Greek.

00:52:52For example,

00:52:54Aristotle's writings

00:52:56were found in the corpus of literature.

00:52:58According to some sources,

00:53:00during this book hunt,

00:53:02if he found books,

00:53:04he took them to the library.

00:53:06If he decided that a book

00:53:08was precious,

00:53:10he made a copy of it

00:53:12that he gave to his owner

00:53:14with a compensation.

00:53:16The original remained at the library.

00:53:18Another story tells us that Ptolemy III,

00:53:20grandson of the founder of the library,

00:53:22offered the governor of Athens

00:53:24a huge compensation

00:53:26for the right to copy the texts

00:53:28of the greatest poets.

00:53:30It was the Roman Empire

00:53:32that, having accessed domination,

00:53:34burned all its knowledge

00:53:36without thinking that this would

00:53:38lead to their own loss.

00:53:40There was then no way

00:53:42to disseminate the information.

00:53:44A single source held

00:53:46most of the knowledge

00:53:48that humanity had accumulated.

00:53:50The great minds were not content

00:53:52to fill it.

00:53:54They also created important

00:53:56correspondences between the works,

00:53:58if the library of Alexandria

00:54:00had not burned,

00:54:02we would have today

00:54:04invaluable knowledge

00:54:06about the people who lived

00:54:08at that time.

00:54:10Some scientists think

00:54:12that this knowledge

00:54:14could have saved the Vikings

00:54:16who settled in Greenland

00:54:18several centuries ago.

00:54:20This could have also helped

00:54:22the population of Easter Island

00:54:24to identify and solve

00:54:26the problem of the soil.

00:54:30It is said that a person living

00:54:32at that time was exposed

00:54:34in one day to as much data

00:54:36as a person of the 15th century

00:54:38during his entire life.

00:54:40And there is a theory

00:54:42that all the papyruses

00:54:44of the library of Alexandria

00:54:46could contain a single USB key.

00:54:50So much data is generated

00:54:52every day that it could

00:54:54We are then talking

00:54:56about an overload of information.

00:54:58We are heading towards

00:55:00a world civilization,

00:55:02so if all this knowledge

00:55:04disappeared, we would lose

00:55:06not an empire, but the whole world.

00:55:08Imagine a wandering planet,

00:55:10a cosmic vagabond

00:55:12that no one would want to

00:55:14accompany at home.

00:55:16Basically, a wandering planet

00:55:18has already been ejected

00:55:20from its own stellar system

00:55:22by a cosmic lone wolf.

00:55:24These planets are not purely theoretical.

00:55:26They exist, and scientists

00:55:28have even detected them in our galaxy.

00:55:30In fact, estimates suggest

00:55:32that there could be a lot of

00:55:34these nomadic cosmos floating

00:55:36around the Milky Way.

00:55:38And they are not just small

00:55:40rocky universes like Earth.

00:55:42Some of them are massive

00:55:44gas giants, several times

00:55:46larger than Jupiter.

00:55:48These mastodons could potentially

00:55:50orbit around them.

00:55:52For example, one of the most

00:55:54famous wandering planets we know

00:55:56bears a complicated name.

00:55:58Here, read it yourself.

00:56:00It is located about 80 light years

00:56:02from Earth, and it was discovered

00:56:04in 2013.

00:56:06Its mass is estimated to be

00:56:08about 6 times that of Jupiter,

00:56:10and it would be about 12 million years old.

00:56:12And yes, it's not because

00:56:14these cosmic loners don't have stars

00:56:16that they are mega-cold.

00:56:18They can still generate heat

00:56:20and light from their own

00:56:22internal processes.

00:56:24Some can even have magnetic fields

00:56:26and auroras, just like Earth.

00:56:28In other words, wandering planets

00:56:30could potentially be habitable

00:56:32if they met the right conditions.

00:56:34So, what would life look like

00:56:36on such a planet?

00:56:38And could we possibly live

00:56:40in such a world?

00:56:42Well, existing on a wandering planet

00:56:44can be a very lonely existence.

00:56:46There is no place to relax,

00:56:48no cozy atmosphere to sunbathe,

00:56:50and no cosmic neighbors to barbecue with.

00:56:52Ouch.

00:56:54That's why we need to be creative.

00:56:56Let's start with the most obvious problem.

00:56:58It will be difficult to get rid of light

00:57:00and heat.

00:57:02How can we solve this problem?

00:57:04Well, we should probably invest

00:57:06in very sophisticated space heating

00:57:08and wear space suits,

00:57:10super warm.

00:57:12We could also invent a whole new way

00:57:14to get solar energy.

00:57:16For example, why not use geothermal energy?

00:57:18This is serious business.

00:57:20Each planet has

00:57:22an internal source of heat.

00:57:24Without it, they would be

00:57:26just cold rocks and lifeless

00:57:28floating in space.

00:57:30This source of heat could be used

00:57:32to power factories

00:57:34and spaceships.

00:57:36It's like having a big enough

00:57:38jacuzzi to power an entire city.

00:57:40And this city will be

00:57:42very safely located underground,

00:57:44closest to the source of heat.

00:57:46As for light,

00:57:48we should probably make

00:57:50ultra-powerful flashlights.

00:57:52Or maybe even learn to

00:57:54genetically create bioluminescent organisms

00:57:56to light our houses.

00:57:58Imagine space bases

00:58:00invaded by mushrooms and fluorescent plants.

00:58:02By the way,

00:58:04speaking of plants,

00:58:06the presence of plants would be

00:58:08quite difficult to obtain without stars.

00:58:10Well, we could use

00:58:12the same geothermal sources we talked about,

00:58:14or some chemical reactions

00:58:16to meet our needs.

00:58:18And maybe we would develop a taste

00:58:20for food rich in sulfur,

00:58:22or we would start fermenting our own drinks

00:58:24from boiling volcanic mud.

00:58:26Yum!

00:58:28But apart from food,

00:58:30we have a bigger problem.

00:58:32Living on an errant planet would be

00:58:34breathtaking, literally,

00:58:36because we would have no air.

00:58:38Errant planets do not have a stable,

00:58:40viable atmosphere.

00:58:42Everything depends on their size,

00:58:44composition, and other factors.

00:58:46But even if our new house

00:58:48had an atmosphere,

00:58:50it could be incredibly thin and precarious.

00:58:52We would not have beautiful blue skies

00:58:54or spectacular sunsets to admire.

00:58:56Instead, we would look

00:58:58into the infinite void of space

00:59:00where the stars would be brighter than ever.

00:59:02And forget about meteorological phenomena.

00:59:04Without atmosphere to create them,

00:59:06we would have no rain,

00:59:08no snow, no storm.

00:59:10And these are just the smallest problems.

00:59:12The worst is that the planet's temperature

00:59:14would fluctuate enormously,

00:59:16going from an unbearable heat

00:59:18to an unbearable cold.

00:59:20It would be like living in an oven

00:59:22that would be constantly turned on and off.

00:59:24And finally, we would be exposed

00:59:26to all kinds of space debris

00:59:28and cosmic radiation.

00:59:30So, if you don't want to turn into chips,

00:59:32you should invest in excellent solar protection.

00:59:34But how can we solve this problem?

00:59:36We would have to find a way

00:59:38to produce our own oxygen

00:59:40and probably create something

00:59:42like a biosphere of space air.

00:59:44For example, we could grow plants

00:59:46capable of generating oxygen,

00:59:48or we could learn to filter the air

00:59:50like a high-tech purifier would.

00:59:52Finally, we have one last problem

00:59:54that is the most important.

00:59:56Find water.

00:59:58And this is where the underwater oceans

01:00:00come in handy.

01:00:02Let's really dive into the heart of the matter.

01:00:04Aha!

01:00:06But seriously, scientists suggest

01:00:08that some of these planets

01:00:10could actually have underwater oceans.

01:00:12It would be like living on a giant water balloon

01:00:14that would have been buried underground

01:00:16with a floor made of ice and rocks.

01:00:18In other words,

01:00:20we could simply drown

01:00:22in these underground oceans.

01:00:24They could provide us with a source of water

01:00:26for food, agriculture and manufacturing.

01:00:28Maybe even other resources

01:00:30that we have never seen before.

01:00:32By the way,

01:00:34who knows what strange creatures

01:00:36could be hiding in these underground oceans?

01:00:38But don't worry,

01:00:40there's nothing to worry about.

01:00:42Even if we don't have an underground oasis,

01:00:44there are still other options.

01:00:46We could get water from comets,

01:00:48ice extraction,

01:00:50and even the atmosphere

01:00:52that we just created earlier.

01:00:54Finally, we have to find and extract resources

01:00:56to build our houses and other things.

01:00:58And a wandering planet

01:01:00doesn't necessarily have the same type of resources

01:01:02as the one orbiting around a star.

01:01:04It's like trying to find treasures

01:01:06in a desert.

01:01:08It's not really a win-win.

01:01:10We may have to rely on the resources

01:01:12of asteroids and other things like that.

01:01:14And if we want to extract resources

01:01:16from the planet itself,

01:01:18we may have to drill kilometers of ice

01:01:20and rocks.

01:01:22But if you're ready to take on the challenge,

01:01:24there's always a chance

01:01:26you'll end up on a wandering planet.

01:01:28And who knows,

01:01:30maybe you'll discover new resources

01:01:32even more precious than gold or diamonds.

01:01:34Great!

01:01:36It looks like we've solved

01:01:38the most important problems.

01:01:40There may still be other small difficulties.

01:01:42For example, we should also face

01:01:44very long days and nights

01:01:46depending on the rotation speed of our planet.

01:01:48And we wouldn't have a normal

01:01:50and regular day-night cycle.

01:01:52The rotation of our planet

01:01:54would be totally unpredictable.

01:01:56Maybe we'd have weeks of night

01:01:58followed by weeks of day,

01:02:00which could really disrupt our sleep schedules.

01:02:02Maybe we should make a particularly strong coffee

01:02:04to keep up

01:02:06during these long and dark nights.

01:02:08But theoretically,

01:02:10we can adapt to all these things

01:02:12and overcome all the challenges.

01:02:14And finally, welcome to the wandering planet,

01:02:16where the sun never rises,

01:02:18but where adventures never stop either.

01:02:20Thanks to our advanced technology,

01:02:22we have managed to create

01:02:24a comfortable and habitable environment

01:02:26in this once sterile world.

01:02:28The sky above us

01:02:30is now a beautiful shade of blue

01:02:32filled with white clouds

01:02:34and an occasional herd of flying creatures.

01:02:36What more could you ask for?

01:02:38When we venture out of our underground habitats,

01:02:40we are welcomed by a world

01:02:42full of surprises.

01:02:44Plants and strange animals

01:02:46have adapted to the unique conditions

01:02:48of this planet,

01:02:50with bioluminescent lights

01:02:52shining in the dark.

01:02:54And be careful if you want to go swimming

01:02:56in the underground oceans.

01:02:58They could house strange creatures

01:03:00who want to feast on...

01:03:02Well, you know what I mean, right?

01:03:04Maybe.

01:03:06As you can see,

01:03:08we have created tentacular cities

01:03:10and prosperous communities

01:03:12powered by the geothermal energy of the planet.

01:03:14We have also created a lot of artificial light sources

01:03:16that illuminate dark and cold nights.

01:03:18We still have a few guiding problems

01:03:20and time measures,

01:03:22but things are not as boring as before, are they?

01:03:24Overall, living on a wandering planet

01:03:26would certainly have its challenges,

01:03:28but it could also be

01:03:30a pretty exciting way to discover the universe.

01:03:32And who knows,

01:03:34maybe one day we will find such a planet

01:03:36and transform it into an animated intergalactic metropolis.

01:03:42But until then, let's take advantage of our dear Earth

01:03:44and protect it.

01:03:46For thousands of years,

01:03:48humans only knew the planets

01:03:50Mercury, Venus, Mars, Jupiter and Saturn,

01:03:52which they could observe

01:03:54with a simple telescope

01:03:56or even with the naked eye

01:03:58if the conditions were met.

01:04:00But in 1781,

01:04:02a famous astronomer,

01:04:04Sir William Herschel,

01:04:06discovered a new planet of icy blue colors.

01:04:08At first, people thought

01:04:10it was a star,

01:04:12but later they realized

01:04:14it was actually a planet.

01:04:16Today, we know it as Uranus,

01:04:18a planet more than 19 times

01:04:20farther from the sun than the Earth.

01:04:22It is so far that it takes

01:04:2484 years to go around the sun.

01:04:28This astronomer also discovered

01:04:30many other interesting things in space,

01:04:32such as double stars and nebulae.

01:04:34In the middle of the 19th century,

01:04:36scientists noticed

01:04:38that something was pulling Uranus

01:04:40and strangely changing its orbit.

01:04:42They thought there must be

01:04:44another planet in space,

01:04:46and they used mathematics

01:04:48to predict where it would be.

01:04:50Finally, they discovered Neptune

01:04:52with a telescope in 1846.

01:04:54It was too visible

01:04:56alone and rising

01:04:58from its hallowing amount of sun.

01:05:00All this was so exciting.

01:05:02Who knows how many other planets

01:05:04could be there,

01:05:06covered in the darkness

01:05:08of our own solar system.

01:05:10Something unusual was happening

01:05:12in the sky.

01:05:14A small teluric planet

01:05:16called Mercury behaved strangely.

01:05:18It did not follow the predictable

01:05:20orbit we expected.

01:05:22One of the astronomers

01:05:24was a brilliant French scientist,

01:05:26Urbain Le Verrier.

01:05:28He came up with a theory

01:05:30that there could be another planet

01:05:32in our solar system that no one

01:05:34had discovered yet,

01:05:36and it would be somewhere

01:05:38in our solar system.

01:05:40The hypothesis that he named Vulcan

01:05:42in reference to the Roman god of the forge

01:05:44would have an incredibly hot surface,

01:05:46and it could constitute

01:05:48a potential explanation

01:05:50for Mercury's strange behavior.

01:05:52He never really claimed

01:05:54that Vulcan was the only thing

01:05:56capable of disrupting Mercury's orbit.

01:05:58But excited by the possibility

01:06:00of discovering a new planet,

01:06:02astronomers from all over the world

01:06:04took hold of the idea.

01:06:06Some scientists did not believe

01:06:08that it was possible

01:06:10that they could have missed

01:06:12another planet as large as Mercury.

01:06:14It would have been difficult

01:06:16not to notice it

01:06:18until then.

01:06:20But there was a slim chance

01:06:22that a smaller planet

01:06:24existed within Mercury's orbit

01:06:26and that it was too close to the sun

01:06:28for anyone to see it.

01:06:30According to a theory,

01:06:32it would be about 13 million

01:06:34kilometers from the sun.

01:06:36Mercury is the planet whose orbit

01:06:38is the most eccentric of our stellar system,

01:06:40but the closest point to the sun

01:06:42is about 28.5 million kilometers.

01:06:44Vulcan would therefore be

01:06:46less than half that distance.

01:07:00Vulcan's position,

01:07:02the furthest from the sun,

01:07:04would still be too close to it

01:07:06to be seen with the naked eye,

01:07:08even at twilight.

01:07:10The only chance to see Vulcan

01:07:12would be during a solar eclipse

01:07:14or when it would pass

01:07:16itself in front of the star,

01:07:18which, according to this theory,

01:07:20would happen 2 to 4 times a year.

01:07:22According to this same theory,

01:07:24the mysterious planet was so close

01:07:26to the sun that it could only be

01:07:28seen during a total solar eclipse

01:07:30Astronomers scrutinized the sun

01:07:32in the hope of seeing Vulcan.

01:07:34They tried, but whatever they did,

01:07:36they could never find

01:07:38this mysterious planet.

01:07:40Some astronomers claimed to have

01:07:42spotted it during an eclipse,

01:07:44but no one was able to confirm it

01:07:46or prove it.

01:07:48The theory of Vulcan

01:07:50gradually faded into oblivion.

01:07:52Einstein had another idea in mind.

01:07:54You know his theory of general relativity,

01:07:56don't you?

01:07:58General relativity was not

01:08:00a kind of natural force,

01:08:02but the result of the curvature

01:08:04of space-time due to the presence

01:08:06of supermassive space bodies

01:08:08like planets and stars.

01:08:10Planets rotate around the sun

01:08:12in their usual orbit

01:08:14because space-time is curved,

01:08:16which means that planets fall

01:08:18in some way towards the central star

01:08:20of our solar system.

01:08:22And Einstein tried to explain

01:08:24Mercury's unusual orbit

01:08:26Contrary to other planets

01:08:28of our solar system,

01:08:30Mercury's orbit was not circular.

01:08:32Instead,

01:08:34it seemed to oscillate slightly,

01:08:36as if an invisible force attracted it.

01:08:38According to Einstein,

01:08:40this phenomenon could have been

01:08:42due to the colossal gravity of our sun

01:08:44that curves the fabric of space-time

01:08:46around it.

01:08:48According to him,

01:08:50it was possible that it slightly

01:08:52modified Mercury's orbit.

01:08:54Although Einstein's theory

01:08:56provided a more elegant explanation

01:08:58of Mercury's strange orbit,

01:09:00some scientists

01:09:02continued to believe in Vulcan.

01:09:04It was all the more difficult

01:09:06to give up the idea

01:09:08that Mercury is also

01:09:10the most difficult planet

01:09:12to observe where we are.

01:09:14But as a result,

01:09:16more and more researchers

01:09:18began to accept Einstein's theory

01:09:20despite their convictions.

01:09:22Then they waited

01:09:24for a total solar eclipse

01:09:26to test Einstein's theory

01:09:28and no longer because of Vulcan.

01:09:30Vulcan is not the only

01:09:32hypothetical planet

01:09:34that everyone has ever talked about.

01:09:36Since the modern era,

01:09:38some estimate that a mysterious planet

01:09:40could be located outside

01:09:42our solar system.

01:09:44But it is more likely to exist.

01:09:46No one has observed it directly yet.

01:09:48But computer simulations

01:09:50show that this so-called

01:09:52planet 9 or planet X

01:09:54would probably be somewhere

01:09:56beyond Neptune.

01:09:58Neptune and planet X

01:10:00could be of similar size.

01:10:02The latter could therefore be

01:10:0410 times larger than Earth

01:10:06and orbit around our sun

01:10:08following an elliptical curve

01:10:10that would be on average

01:10:1220 times farther from the sun than Neptune.

01:10:14A year could last there

01:10:16between 10,000 and 20,000 terrestrial years.

01:10:18For comparison,

01:10:20a year on Neptune lasts 100,

01:10:22105 terrestrial years.

01:10:24An object of this size

01:10:26moving beyond Neptune

01:10:28could explain the strange orbits

01:10:30of some objects in the belt of Kuiper.

01:10:32This belt is the zone

01:10:34of our solar system

01:10:36which is located beyond Neptune

01:10:38and its orbit.

01:10:40There are very likely

01:10:42numerous asteroids,

01:10:44discometies,

01:10:46principal elements

01:10:48constituis des glaces.

01:10:50There is another hypothetical planet

01:10:52named Nibiru.

01:10:54Do you remember these rumors

01:10:56of the end of the world in 2012?

01:10:58One of the most popular scenarios

01:11:00was that of Nibiru which,

01:11:02according to some,

01:11:04was supposed to hit our planet

01:11:06at the end of the year.

01:11:08Of course, nothing happened.

01:11:10We are still there.

01:11:12But the idea of Nibiru

01:11:14is that a man named Zecharia Sitchin

01:11:16mentioned Nibiru in his book

01:11:18The Twelfth Planet,

01:11:20claiming that it orbited around the sun

01:11:22every 3,600 years.

01:11:24But there is no chance

01:11:26that a planet with such an eccentric orbit

01:11:28does not disturb the other planets

01:11:30of our solar system with its own gravity.

01:11:32And if it was really

01:11:34so close to Earth in 2012,

01:11:36we were supposed to be able to distinguish it

01:11:38with the naked eye.

01:11:40Simple calculations have shown

01:11:42that Nibiru is almost as bright as Mars

01:11:44in its lowest luminosity

01:11:46and brighter than the lowest stars

01:11:48that can be observed in the city.

01:11:50Maybe we will have more chance

01:11:52in the 3,500 years to come.

01:11:54In 2011,

01:11:56a comet named Elena appeared

01:11:58and many thought

01:12:00it could be the famous Nibiru.

01:12:02But when we observe comets

01:12:04and planets with telescopes,

01:12:06we realize that they have a different appearance.

01:12:08The comet has a chevrolet

01:12:10that is a gaseous atmosphere

01:12:12and it looks like a planet

01:12:14in its orbit.

01:12:16In addition, this comet did not hit Earth.

01:12:18It got too close to our sun

01:12:20and then disintegrated.

01:12:22The remaining debris will continue

01:12:24to move towards the external solar system

01:12:26for the next 12,000 years.

01:12:34The vast expanses of the universe

01:12:36contain an infinity of secrets and possibilities.

01:12:38And here is one of the most intriguing questions.

01:12:40What would life look like

01:12:42and us as humans

01:12:44on other planets?

01:12:46Imagine a world where the laws of physics,

01:12:48the conditions and the environment

01:12:50are so different from what we are used to.

01:12:52How would we evolve

01:12:54to adapt to these new strange lands?

01:12:58Let's see.

01:13:00Mercury is the planet closest to the sun

01:13:02and has a very fine atmosphere.

01:13:04The temperatures there are extreme,

01:13:06the day reaching more than 426 ° C

01:13:08and the night

01:13:10going down to less than 179 ° C.

01:13:14So,

01:13:16what can we do to survive

01:13:18at these insane temperatures

01:13:20and constant solar radiation?

01:13:22We can perhaps turn into metal

01:13:24as if by magic.

01:13:26Titanium and platinum, for example,

01:13:28can perfectly withstand these high temperatures.

01:13:30But more seriously,

01:13:32there is a solution.

01:13:34The temperatures are not so extreme.

01:13:36If we lived underground,

01:13:38we could develop big eyes

01:13:40to better capture the light.

01:13:42We could also have a thicker skin

01:13:44to protect us from intense radiation.

01:13:46In fact, we have two options.

01:13:48Become Iron Man

01:13:50or become moles.

01:13:52Let's move on to Venus.

01:13:54This planet is extremely hostile.

01:13:56First of all, Venus is known

01:13:58for its thick atmosphere,

01:14:00more toxic than your ex.

01:14:02The planet is covered with carbon dioxide

01:14:04and its surface is completely dry,

01:14:06which makes it incredibly suffocating.

01:14:08The average temperature there

01:14:10is about 452 ° C,

01:14:12which makes it one of the

01:14:14warmest planets in our solar system.

01:14:16Do not forget

01:14:18the incredible pressure that reigns there.

01:14:20Staying on Venus is like

01:14:22diving 920 meters underwater.

01:14:24Only the most resistant terrestrial microbes

01:14:26could survive in such conditions.

01:14:28So, if you want to live on Venus,

01:14:30you may have to transform

01:14:32into a microbe.

01:14:34Alas, as we are not microorganisms,

01:14:36we would have to wear special equipment

01:14:38to survive.

01:14:40Maybe we should develop

01:14:42an exoskeleton resistant to heat

01:14:44to protect us,

01:14:46as well as new lungs

01:14:48capable of filtering the toxic particles

01:14:50from this atmosphere.

01:14:52Let's talk about our favorite

01:14:54scarlet cousin, Mars.

01:14:56The first notable change

01:14:58is that gravity on Mars

01:15:00is much weaker than on Earth,

01:15:02so your muscles and bones

01:15:04will tend to atrophy.

01:15:06To compensate for this difference,

01:15:08you will have to eat more

01:15:10and probably go to the gym.

01:15:12You will also have to adapt

01:15:14to low atmospheric pressure

01:15:16and colder temperatures.

01:15:18You need a way to keep

01:15:20the heat, right?

01:15:22This means that you will have

01:15:24a thicker layer of fat.

01:15:26An important change would occur

01:15:28at the skin level.

01:15:30Your skin is like a big barrier

01:15:32that protects you from discomforts

01:15:34such as bacteria, UV rays

01:15:36or the fact of looking like

01:15:38a scorched monster.

01:15:40What would happen then?

01:15:42Well, you would probably

01:15:44turn orange,

01:15:46because of carotenoids.

01:15:48Carotenoids are a type of nutrient

01:15:50found in foods such as carrots,

01:15:52potatoes, tomatoes, etc.

01:15:54They have only one drawback.

01:15:56If you eat too many pumpkins

01:15:58grown on the spot,

01:16:00you will gradually turn orange.

01:16:02But it may not be so bad.

01:16:04Maybe life on Jupiter would be easier?

01:16:06Oh yes, surely!

01:16:08Except that there is no solid ground.

01:16:10This planet is composed of hydrogen and helium,

01:16:12and that's why it's called a gas giant.

01:16:14You would simply fall

01:16:16through huge clouds.

01:16:18And even if you managed to land

01:16:20and walk on something,

01:16:22you would end up in a fog.

01:16:24So how would we evolve there?

01:16:26First, our size could change

01:16:28to resist the immense pressure.

01:16:30Second, the fluctuations

01:16:32of temperature on Jupiter are huge.

01:16:34The surface is terribly cold

01:16:36and the temperature increases considerably

01:16:38under the outer layers of the atmosphere.

01:16:42Third, if you lived on Jupiter,

01:16:44there would be no oral language.

01:16:46This gas giant absorbs radio waves.

01:16:48So even if you spoke,

01:16:50no one could hear you.

01:16:52There would be no music either,

01:16:54so no party.

01:16:56Maybe we could communicate

01:16:58in sign language?

01:17:00But it's not that simple.

01:17:02Jupiter is perpetually agitated

01:17:04by violent winds and powerful storms.

01:17:06So it is unlikely that you can see anything there.

01:17:08Even if we evolve in one way or another,

01:17:10our life would not be easy there.

01:17:12Before landing on Saturn,

01:17:14you will probably want to admire

01:17:16its emblematic rings up close.

01:17:18But that's impossible,

01:17:20because the rings of Saturn

01:17:22are made up of a lot of ice particles

01:17:24floating in space.

01:17:26So it would be extremely difficult to land.

01:17:28So let's go straight to Saturn.

01:17:30At first glance,

01:17:32this planet doesn't seem so bad.

01:17:34Some layers of this gas giant

01:17:36have rather pleasant temperatures.

01:17:38If we dive deeper into the planet,

01:17:40it is even relatively warm,

01:17:42up to minus 3 degrees in its second layer.

01:17:44This is an average temperature

01:17:46Unfortunately,

01:17:48it is only one of its many layers.

01:17:50The rest of the planet is incredibly cold.

01:17:52To survive on Saturn,

01:17:54we would have to make a lot of effort.

01:17:56In addition to the cold,

01:17:58we would have to accommodate

01:18:00the hostile environment of the planet,

01:18:02in particular its extreme storms,

01:18:04its violent winds and its radiation.

01:18:06To protect us from these conditions,

01:18:08we would still need to develop

01:18:10a resistant skin,

01:18:12isolation techniques, etc.

01:18:14The next planet is Uranus.

01:18:16The environment of Uranus is very different

01:18:18from that of Earth,

01:18:20with much colder temperatures,

01:18:22the absence of solid surfaces

01:18:24and a very different atmosphere.

01:18:26It's like another Jupiter,

01:18:28but in blue tones.

01:18:30But we could fall worse.

01:18:32There is even water on Uranus.

01:18:34The only problem is that the planet

01:18:36is full of ammonia,

01:18:38this radical product

01:18:40that we use for cleaning.

01:18:42How to survive in such a dark

01:18:44and hostile environment?

01:18:46We would need a thicker skin

01:18:48to face these extreme temperatures.

01:18:50We would also need a bigger eye

01:18:52to see better in the dark.

01:18:54Finally, we could be led to develop

01:18:56a new auditory system,

01:18:58like that of dolphins.

01:19:00It would be pretty funny, wouldn't it?

01:19:02Let's move on to Neptune.

01:19:04If human beings were to evolve on Neptune,

01:19:06they would have to adapt

01:19:08to these difficult conditions.

01:19:10Neptune is another gas giant.

01:19:12The only difference is that this planet

01:19:14could well have a solid core.

01:19:16If we were to live on Neptune,

01:19:18we would have no choice but to float

01:19:20or swim through its methane-rich atmosphere.

01:19:22We would also have to develop branches

01:19:24or a similar device to breathe.

01:19:26In fact, we would become either reptiles

01:19:28from space or cosmic fish.

01:19:30On Neptune, gravity

01:19:32is slightly higher than that of Earth,

01:19:34but violent winds make it very difficult

01:19:36to stay in place.

01:19:38If we were to stay in the wind,

01:19:40we would have to be much heavier.

01:19:42Again, it's about eating a lot

01:19:44and working out.

01:19:46Yes, yes, technically,

01:19:48it's not a planet,

01:19:50but we still love them

01:19:52and we can't leave them alone.

01:19:54A small, distant and incredibly cold world.

01:19:56Pluto is even smaller than our Moon.

01:19:58And for this reason,

01:20:00there is almost no gravity.

01:20:02It will therefore be very difficult

01:20:04to stand on it.

01:20:06And if we don't want to have vertigo,

01:20:08we will have to develop

01:20:10a whole new nervous system.

01:20:12But Pluto could be worse.

01:20:14For example, there is liquid water

01:20:16under its surface,

01:20:18and even some frozen mountains.

01:20:20It might be possible to survive

01:20:22if we had adequate equipment,

01:20:24clothes, supplies, and...

01:20:26No, forget it, life is too complicated.

01:20:28Whatever the theory of Mercury's heat

01:20:30to Neptune's glacial temperature,

01:20:32each planet presents a unique set

01:20:34of potentials and opportunities for evolution.

01:20:36Even if we will never know

01:20:38what humans would look like

01:20:40on these other worlds,

01:20:42it is fascinating to consider

01:20:44the infinite possibilities

01:20:46that are offered to us.

01:20:48Let's never stop looking

01:20:50towards the stars

01:20:52and asking ourselves such questions.

01:20:54Exploring the vast expanses

01:20:56of the universe,

01:20:58scientists have made

01:21:00incredible discoveries.

01:21:02These exoplanets,

01:21:04discovered in 2022,

01:21:06are really out of the ordinary.

01:21:08So hang on,

01:21:10because the future of these discoveries

01:21:12is more radiant than ever.

01:21:14Number 1. New types of exoplanets.

01:21:16Red dwarfs represent

01:21:18more than 70% of all stars.

01:21:20In September 2022,

01:21:22scientists decided to examine

01:21:24the little worlds

01:21:26that revolve around them.

01:21:28And what they observed

01:21:30were exoplanets made up

01:21:32of half rocks and half water

01:21:34in the form of liquid or ice.

01:21:36According to the researchers,

01:21:38these planets would come from

01:21:40a material from far away,

01:21:42beyond the line of ice,

01:21:44where temperatures are extremely low.

01:21:46They would then be brought

01:21:48closer to their star

01:21:50where astronomers detected them.

01:21:52This discovery could have

01:21:54enormous repercussions

01:21:56on the quest for life in the cosmos.

01:21:58Number 2. A Jupiter-sized world.

01:22:00Imagine a massive and mysterious planet,

01:22:02a kind of Jupiter

01:22:04hidden in the galaxy.

01:22:06Well, we have just discovered

01:22:08one orbiting a star

01:22:10located at 379 light-years away.

01:22:12We called it TOI 2180 b,

01:22:14and it's already talking about it.

01:22:16Why?

01:22:18First of all,

01:22:20because it is a planet

01:22:22that is not entirely covered

01:22:24by the ocean.

01:22:26This is much longer

01:22:28than most of the gas giants

01:22:30we have observed so far.

01:22:32But that's not all.

01:22:34The temperatures of this world

01:22:36are surprisingly low,

01:22:38with an average of 77 degrees.

01:22:40In comparison,

01:22:42it is between

01:22:44minus 189 and minus 139 degrees Celsius

01:22:46on a planet like Saturn.

01:22:48It is actually a link

01:22:50between the recently discovered

01:22:52giant exoplanets

01:22:54and our Jupiter.

01:22:56But the question remains,

01:22:58why is this planet so different?

01:23:00Scientists are still looking

01:23:02to understand.

01:23:04Let's hope we will soon have answers.

01:23:06Number 3. The Hulk planet.

01:23:08The surface of this planet

01:23:10is covered with fusion magma

01:23:12and a year is only half a day long.

01:23:14Welcome to TOI 1075 b,

01:23:16an exoplanet

01:23:18nicknamed Hulk planet

01:23:20by scientists.

01:23:22Located 200 light-years away,

01:23:24this super-Earth

01:23:26is one of the most massive

01:23:28ever discovered.

01:23:30Its proximity to its star

01:23:32makes its surface reach

01:23:34a temperature of 1050 degrees Celsius.

01:23:36The heat is such

01:23:38that the rock evaporates instantly

01:23:40and the air is filled

01:23:42with vaporized rocks.

01:23:44But if its temperature is impressive,

01:23:46its size is even greater.

01:23:48TOI 1075 b

01:23:50is almost ten times bigger

01:23:52than Earth's,

01:23:54making it one of the biggest

01:23:56super-Earths ever discovered.

01:23:58But the mystery does not end there.

01:24:00This planet orbits in only 14.5 hours,

01:24:02making it one of the shortest

01:24:04orbital periods ever recorded

01:24:06for a planet of this size.

01:24:08Enough to enrich our catalogue

01:24:10in an exciting way.

01:24:12Number 4. Three condemned planets.

01:24:14Astronomers have discovered

01:24:16three planets evolving

01:24:18in a dangerous dance

01:24:20next to declining stars.

01:24:22Ten years ago,

01:24:24scientists did not even imagine

01:24:26that such planets could exist.

01:24:28These gas giants,

01:24:30similar in size to Jupiter's,

01:24:32orbit far too close to their star.

01:24:34They practically walk

01:24:36on the razor's edge.

01:24:38Let's take the example of one of them,

01:24:40called TOI 2337 b.

01:24:42In less than a million years,

01:24:44its orbit will rush it

01:24:46I wouldn't be here anymore,

01:24:48of course.

01:24:50As these stars live their last days,

01:24:52they attract their neighbours

01:24:54like black holes,

01:24:56modifying their orbits

01:24:58and risking to cause

01:25:00catastrophic collisions.

01:25:02In addition, as these planets

01:25:04get closer, their atmospheres

01:25:06heat up, causing incredible

01:25:08density differences.

01:25:10But the study of these worlds

01:25:12could provide us with precious

01:25:14information about our solar system.

01:25:18Number 5.

01:25:20An atmosphere of barium.

01:25:22Here are two extremely hot planets,

01:25:24each with an atmosphere

01:25:26made up of the heaviest element

01:25:28ever found on an exoplanet,

01:25:30barium.

01:25:32These planets, WASP 70 b

01:25:34and WASP 121 b,

01:25:36are gas giants,

01:25:38known as ultra-hot Jupiters,

01:25:40orbiting very close to their star.

01:25:42They are like fireballs,

01:25:44with one side facing the star

01:25:46and cooking at high temperatures

01:25:48to vaporize iron and other metals.

01:25:50And when the iron vapour is swept

01:25:52towards the nocturnal side of the planet,

01:25:54it turns into liquid

01:25:56and falls in the form of an iron rain.

01:25:58And these planets have

01:26:00a little surprise in store for us.

01:26:02Barium is a heavy metal,

01:26:04about 2.5 times heavier than iron.

01:26:06Yet scientists have detected

01:26:08it in the upper layers of their atmosphere.

01:26:10This is a real mystery

01:26:12that we are still trying to solve.

01:26:14Imagine landing

01:26:16on such a planet

01:26:18and seeing an iron and barium averse.

01:26:20It would be absolutely terrifying.

01:26:24Number 6. The Balloon Planet.

01:26:26Get ready to be blown away.

01:26:28We have just discovered

01:26:30a planet in the form of

01:26:32an American football ball.

01:26:34And it looks nothing like

01:26:36what we have seen so far.

01:26:38Here is WASP-103b,

01:26:40an ultra-hot exoplanet

01:26:42located more than 1,000 light-years away

01:26:44from Earth.

01:26:46This gas giant,

01:26:48very close to its star,

01:26:50is deformed by an intense gravitational force.

01:26:52But it's not just

01:26:54a funny oddity.

01:26:56It's also a precious scientific discovery.

01:26:58By studying the passages

01:27:00of the planet around its star,

01:27:02we were able to measure its deformation.

01:27:04It's as if we were

01:27:06taking an instant of a moving planet

01:27:08and it gave us indications

01:27:10of the extreme conditions

01:27:12that these objects can endure.

01:27:14It's really a great discovery.

01:27:16Number 7. A Zodiacal Light.

01:27:20Ready for a cosmic ghost story?

01:27:22Chinese scientists

01:27:24have discovered a frightening phenomenon

01:27:26on three distant exoplanets.

01:27:28This is the Zodiacal Light,

01:27:30a light similar to

01:27:32the one we see on Earth

01:27:34in the sunset.

01:27:36But it's not just a strange sight.

01:27:38We could have clues

01:27:40about the composition of these potentially habitable worlds.

01:27:42Imagine that you look at the sunset

01:27:44from a dark place on Earth

01:27:46and that, instead of darkness,

01:27:48a triangle of light appears.

01:27:50This is the Zodiacal Light.

01:27:52It's due to the reflection of the sun's light

01:27:54on the dust particles of the solar system,

01:27:56the remains of asteroids and comets.

01:27:58Researchers have analysed

01:28:0047 potentially habitable exoplanets

01:28:02and discovered that

01:28:04three of them, called Kepler-69c,

01:28:06Kepler-1229b

01:28:08and Kepler-395c,

01:28:10all super-Earths,

01:28:12presented this phenomenon.

01:28:14This discovery could give us a lot of information.

01:28:16It could reveal information

01:28:18about the presence of asteroids and comets

01:28:20in these systems.

01:28:22It would be very difficult to detect them otherwise.

01:28:24So it's pretty cool.

01:28:26Number 8.

01:28:28A planet with silicate clouds.

01:28:30This is VHS-1256b.

01:28:32Nothing to do

01:28:34with video tapes.

01:28:36It's a strange and exotic world

01:28:38full of mystery.

01:28:40A place where the clouds are made of sand

01:28:42and where the sky is always red.

01:28:44It's not science fiction,

01:28:46but a real discovery

01:28:48made by the brilliant brains of NASA.

01:28:50This exoplanet,

01:28:52Nen Brune,

01:28:54makes waves in the astronomical community.

01:28:56It is far too massive

01:28:58to be a planet,

01:29:00almost 20 times the size of Jupiter.

01:29:02But it's not quite a star either.

01:29:04It's something intermediate,

01:29:06a cosmic enigma that defies any definition.

01:29:08But what is really extraordinary

01:29:10with VHS-1256b

01:29:12is its atmosphere.

01:29:14Scientists have discovered that this strange world

01:29:16is enveloped by thick clouds of silicate grains,

01:29:18similar to sand.

01:29:20This is the first time

01:29:22that this type of cloud is detected on an exoplanet.

01:29:24This discovery

01:29:26will not fail to modify

01:29:28our perception of the universe

01:29:30and the possibilities of life beyond our own world.

01:29:32And that's it.

01:29:34The year 2022 was rich

01:29:36in incredible and revolutionary discoveries

01:29:38concerning exoplanets.

01:29:40But this is just the beginning.

01:29:42We can only imagine

01:29:44the other wonders

01:29:46that await us as scientists

01:29:48and researchers continue to explore

01:29:50the vast expanses of space.

01:29:52So let's continue to study our beautiful sky.

01:29:54Who knows what secrets

01:29:56the stars still hold for us?

01:29:58Let me tell you

01:30:00a little story.

01:30:02In a very, very distant stellar system,

01:30:042,600 light years away,

01:30:06to be more precise,

01:30:08there is an exoplanet

01:30:10called Kepler-1658b.

01:30:12It's a gas giant

01:30:14similar to our Jupiter.

01:30:16But what sets it apart from Jupiter

01:30:18is that this poor planet

01:30:20is doomed.

01:30:22It will spiral towards its star,

01:30:24which will end up causing

01:30:26a burning collision.

01:30:28But the most interesting thing is

01:30:30that astronomers would have remained

01:30:32totally ignorant of this fact

01:30:34if they had not had a very small clue.

01:30:36It was an absolutely tiny change

01:30:38in the orbit of this planet.

01:30:40And it would have gone completely unnoticed

01:30:42if astronomers had not compared

01:30:44more than a decade of data

01:30:46collected by different telescopes.

01:30:48Concretely,

01:30:50astronomers observed this exo-Jupiter

01:30:52passing between our planet

01:30:54and its star once every two weeks

01:30:56over the last 13 years.

01:30:58And they noticed

01:31:00that the planet's orbit

01:31:02was getting smaller and smaller.

01:31:04Every year,

01:31:06Kepler-1658b needs

01:31:08131 milliseconds less

01:31:10to make a revolution

01:31:12around its star.

01:31:14If this trend continues,

01:31:16the planet will certainly collide

01:31:18in 2.5 million years.

01:31:20Even before this discovery,

01:31:22computer simulations

01:31:24already predicted that some planets

01:31:26could eventually crash

01:31:28on their star.

01:31:30But this is the first time astronomers

01:31:32have acquired concrete evidence

01:31:34of such an outcome

01:31:36by measuring almost imperceptible changes

01:31:38in the orbit of a celestial body.

01:31:40They now know for sure

01:31:42what happens when a planet

01:31:44is about to crash on its star,

01:31:46but they're probably not there

01:31:48to witness it.

01:31:50But let me tell you a little more

01:31:52about this doomed planet.

01:31:54It was discovered by NASA's

01:31:56Kepler Space Telescope,

01:31:58now out of service.

01:32:00Launched in 2009,

01:32:02its mission was to find planets

01:32:04orbiting other stars,

01:32:06called exoplanets.

01:32:08And the very first exoplanet

01:32:10spotted by the telescope

01:32:12was the gas giant we just mentioned.

01:32:14To confirm that this space body

01:32:16was indeed an exoplanet.

01:32:18This star is like a denser version

01:32:20of Jupiter.

01:32:22It takes the equivalent of 6 Jupiters

01:32:24in terms of matter,

01:32:26compresses them into a ball

01:32:28about 1.1 times bigger,

01:32:30and that's the job.

01:32:32The planet is in synchronous rotation

01:32:34with its star,

01:32:36which means it makes a full turn

01:32:38every time it completes a revolution

01:32:40around the star.

01:32:42And that's the job of the gas giant

01:32:44facing the star.

01:32:46It's the same thing for our Moon.

01:32:48Our natural satellite

01:32:50is in gravitational lock with the Earth.

01:32:52That's why we only see

01:32:54half of its surface.

01:32:56What attracts the exo-Jupiter

01:32:58to its star?

01:33:00Well, it's the same process

01:33:02that moves the Moon away from the Earth.

01:33:04When a Moon is in orbit around a planet,

01:33:06or when a planet is in orbit

01:33:08around a star,

01:33:10the two gravities interact

01:33:12and exert an attraction on the mass of the other.

01:33:14That's what causes the tides on Earth.

01:33:16This attraction releases energy

01:33:18and it can accelerate

01:33:20or slow down an object.

01:33:22In the first case,

01:33:24the space body will move away little by little.

01:33:26In the second,

01:33:28it will start to get closer.

01:33:30And that's exactly what happens

01:33:32to this gas giant.

01:33:34Its star has a mass 1.5 times higher

01:33:36than that of our Sun.

01:33:38So it's not surprising that these tides

01:33:40gradually slow down the movement

01:33:42of the planet,

01:33:44attracting it inwards.

01:33:46All of this seems quite tragic.

01:33:48But this potential collision is not,

01:33:50by far, the strangest thing

01:33:52that happens in space.

01:33:54Let's look at other cases.

01:33:56Betelgeuse, for example,

01:33:58a red giant located in the constellation

01:34:00of Orion, started to darken

01:34:02in 2019.

01:34:04And that disconcerted astronomers.

01:34:06At that time,

01:34:08the star had already swelled

01:34:10to reach phenomenal proportions.

01:34:12If it had to replace our Sun,

01:34:14its surface would extend well beyond

01:34:16Jupiter's orbit.

01:34:18Then Betelgeuse became less bright

01:34:20during the fall of 2019.

01:34:22And this process continued

01:34:24until February 2020.

01:34:26The changes were perceptible to the naked eye.

01:34:28And for good reason.

01:34:30The brightness of the star had dropped

01:34:32by two thirds.

01:34:34At that time, astronomers were convinced

01:34:36that Betelgeuse was about

01:34:38to explode into a supernova.

01:34:40They continued to observe the star,

01:34:42but unexpectedly,

01:34:44it regained its usual brightness.

01:34:46Thanks to the Hubble Space Telescope,

01:34:48scientists understood

01:34:50that the star had ejected

01:34:52part of its matter

01:34:54and that it partially blocked

01:34:56its light.

01:34:58What would you say about exoplanets

01:35:00like Barbapapa?

01:35:02Barbapapa is a star

01:35:04located outside our Solar System.

01:35:06Also known as Superpuff,

01:35:08they have the lowest density

01:35:10ever recorded,

01:35:12which gives them an airy

01:35:14and fluffy appearance.

01:35:16Although they look like

01:35:18the most emblematic snack

01:35:20of amusement parks,

01:35:22these planets are absolutely huge.

01:35:24To think about it,

01:35:26scientists constantly discover

01:35:28very strange things in space.

01:35:30For example,

01:35:32a strange object

01:35:34that looks like

01:35:36no other known space object.

01:35:38ORCs, or strange radio circles,

01:35:40are only visible

01:35:42through radiotelescopes.

01:35:44They could be supernova remains,

01:35:46but some astronomers

01:35:48even claim

01:35:50that they could be

01:35:52the entrance of a glass hole.

01:35:54They are hypothetical tunnels

01:35:56between two points

01:35:58in the Milky Way.

01:36:00Their unusual formation

01:36:02consisted of blue transitory

01:36:04luminous phenomena

01:36:06hovering above the planet's surface.

01:36:08They were two types of

01:36:10sparkling lightning

01:36:12that occur for short periods

01:36:14of time, a few milliseconds

01:36:16at most.

01:36:18They spread from top to bottom

01:36:20to the planet's surface.

01:36:22On Earth, these lightnings

01:36:24generally occur at a height

01:36:26of a few millimeters.

01:36:28Perhaps because they simply

01:36:30don't have any.

01:36:32These space bodies

01:36:34float freely across the Universe

01:36:36and can literally be found

01:36:38anywhere.

01:36:40They are also quite difficult

01:36:42to detect because

01:36:44wandering planets

01:36:46produce only low-emissions.

01:36:48But not so long ago,

01:36:50astronomers spotted

01:36:52the smallest wandering planet

01:36:54in the Milky Way.

01:36:56It has a radio wavelength

01:36:58of a few milliseconds,

01:37:00but it receives as much energy

01:37:02as our Sun produces

01:37:04in several days.

01:37:06Most of these fast radio waves

01:37:08come from far away,

01:37:10far beyond the Milky Way.

01:37:12But recently, astronomers

01:37:14detected a few

01:37:16from our own galaxy,

01:37:18and their source

01:37:20was a magnetar

01:37:22which is the strongest

01:37:24material in the Universe.

01:37:26Formed from the remains

01:37:28of extinguished stars,

01:37:30this substance is compressed

01:37:32to form layers of matter

01:37:34similar to spaghetti.

01:37:36They can break,

01:37:38but only if you apply

01:37:4010 billion times the pressure

01:37:42necessary to break the steel.

01:37:44Not so long ago,

01:37:46researchers discovered

01:37:48that one of the stars

01:37:50was 75 million light-years away.

01:37:52Normally,

01:37:54it's too far for astronomers

01:37:56to clearly distinguish

01:37:58individual stars,

01:38:00unless they are huge.

01:38:02And the star we're talking about

01:38:04was clearly shining 2.5 million times

01:38:06brighter than our Sun.

01:38:08Astronomers saw this star

01:38:10for the last time in 2011.

01:38:12They decided to examine it

01:38:14more closely after a few years,

01:38:16but it was already too late.

01:38:18Such massive stars

01:38:20usually end their existence

01:38:22in extremely bright supernovas.

01:38:24But astronomers

01:38:26didn't notice anything like this.

01:38:28There is a theory

01:38:30that the star would collapse

01:38:32into a black hole

01:38:34without producing supernovas beforehand.

01:38:36This phenomenon happens

01:38:38at the end-of-life of stars,

01:38:40but remains extremely rare.

01:38:42There are black holes,

01:38:44and there could also be

01:38:46supernovae,

01:38:48but their existence

01:38:50has not yet been proven.

01:38:52Unlike their huge cousins,

01:38:54these hypothetical mini-black holes

01:38:56could be really, really tiny,

01:38:58not bigger than an atom.

01:39:00Their mass could vary,

01:39:02but these miniature bodies

01:39:04could have the mass

01:39:06of a thousand cars.

01:39:08A theory says

01:39:10that a huge amount

01:39:12of micro-black holes

01:39:14could be crossed

01:39:16by one or two mini-black holes

01:39:18every day.

01:39:20More than 7,000 light-years away

01:39:22is the Nebula of the Eagle,

01:39:24a young cluster of stars

01:39:26only 5.5 million years old.

01:39:28The Hubble Space Telescope

01:39:30managed to take a photo

01:39:32of several dark shapes

01:39:34near the centre of this nebula.

01:39:36These are the pillars of creation,

01:39:38an active region of star formation.

01:39:40Admittedly, it has style!

01:39:4450 cm with Earth's gravity.

01:39:46Checked.

01:39:48Now the simulator

01:39:50will recreate Mercury's surface.

01:39:52Wow, it's super hot here!

01:39:54Yes, it's like being

01:39:56next to a volcano.

01:40:04You jump to a height of 1.20 m.

01:40:06Let's go to Venus.

01:40:08Wow, that's scary!

01:40:10On the real planet Venus,

01:40:12everything is toxic.

01:40:18Yes, the gravity on Venus

01:40:20is almost the same as on Earth.

01:40:22Let's go to the Moon.

01:40:28The gravity on the Moon

01:40:30is 10 times less strong

01:40:32than on Earth.

01:40:342.70 m.

01:40:36The next planet is Mars.

01:40:38Not bad here!

01:40:40The gravity on Mars

01:40:42is the same as on Mercury.

01:40:461.20 m.

01:40:48Get ready to struggle now!

01:40:50What? What are you...

01:40:52There is no solid surface

01:40:54on Jupiter.

01:40:56Although Jupiter is larger in size,

01:40:58its surface gravity

01:41:00is only 2.4 times stronger

01:41:02than Earth's.

01:41:04It's good for me!

01:41:06Let's go to Saturn.

01:41:08No solid surface here either.

01:41:10Saturn's gravity is more or less

01:41:12the same as Earth's.

01:41:14Let's go to Uranus.

01:41:18It's so cold!

01:41:20Here, however, it's 5 times hotter

01:41:22than on the real planet Uranus.

01:41:241.20 m.

01:41:26Let's go to Uranus.

01:41:281.20 m.

01:41:30It's so cold!

01:41:32It's 5 times hotter

01:41:34than on the real planet Uranus.

01:41:36I can't feel my legs anymore!

01:41:381.20 m.

01:41:40The gravity is so less strong

01:41:42than on Earth.

01:41:441.20 m.

01:41:46Get me out of here!

01:41:481.20 m.

01:41:50We discovered Kepler-22b,

01:41:52a small exoplanet

01:41:54in the sign constellation.

01:41:56Does it seem trivial to you?

01:41:58Actually, it's very important.

01:42:00Kepler-22b is a planet

01:42:02located in the habitable zone

01:42:04discovered by the Kepler telescope.

01:42:06In other words,

01:42:08there may be water on this planet.

01:42:10And if there is water,

01:42:12there may be life.

01:42:14Kepler-22b could become

01:42:16our new home.

01:42:18So let's take a closer look.

01:42:20You should know that discovering

01:42:22new planets is not easy at all.

01:42:24Not all of them can be seen

01:42:26by our ultra-sophisticated telescopes,

01:42:28but sometimes stars are so small

01:42:30and dull that it is difficult

01:42:32to find them in the sky.

01:42:34This is the case with Kepler-22.

01:42:36Scientists had to use a special method.

01:42:38First, they take a lot of pictures

01:42:40of the star at different times.

01:42:42Then they observe

01:42:44and wonder if there are dark spots

01:42:46on this star somewhere.

01:42:48If they find one,

01:42:50it means it could be a planet.

01:42:52These pictures help us discover

01:42:54very important things.

01:42:56For example, the size, radius

01:42:58and proximity to the star.

01:43:00And finally,

01:43:02we can study the question

01:43:04of whether we could live there.

01:43:06We now know that Kepler-22b

01:43:08is very similar to our planet

01:43:10and could potentially become

01:43:12a second Earth.

01:43:14It is also very close to us

01:43:16at only 635 light years.

01:43:18Of course, that's about

01:43:203 quadrillion kilometers.

01:43:22But it's one of the closest options.

01:43:24Kepler-22, the star of Kepler-22b,

01:43:26is a yellow dwarf.

01:43:28It is very similar to our Sun.

01:43:30Same size, same radius,

01:43:32even its age is almost identical.

01:43:344 billion years.

01:43:36The difference lies

01:43:38only in its luminosity.

01:43:40It is about 20% later than the Sun.

01:43:42So, even if you fold your eyes,

01:43:44you won't see this star

01:43:46in the night sky.

01:43:48Planet Kepler-22b

01:43:50is about 2.4 times larger

01:43:52than our Earth.

01:43:54And that's a good thing.

01:43:56A larger radius means more water

01:43:58and potential space to live.

01:44:00Even if going from one city to another

01:44:02would take some time.

01:44:04Imagine a three-day flight.

01:44:06We don't know the exact mass of this planet,

01:44:08but scientists think it is higher

01:44:10than that of the Earth.

01:44:12It could even be up to 36 times

01:44:14higher than that of our planet.

01:44:16What does that mean?

01:44:18A huge gravity.

01:44:20If the planet is 36 times heavier

01:44:22than the Earth,

01:44:24then the gravity there will be

01:44:26about 6 times stronger.

01:44:28You can barely carry a bag

01:44:30of 10 kilos of potatoes,

01:44:32so try a bag of 50 kilos.

01:44:34Not to mention that you can

01:44:36become much heavier yourself

01:44:38on this planet.

01:44:40You will have to be incredibly muscular

01:44:42just to walk there and go to work.

01:44:44The worst thing is that with such gravity,

01:44:46it would be incredibly difficult

01:44:48They need at least a little freedom

01:44:50to get up from the ground.

01:44:52What about the animals?

01:44:54Our dogs and cats should turn into

01:44:56small balls of muscle to survive there.

01:44:58But if this planet already has

01:45:00its own animals or other inhabitants,

01:45:02we can roughly imagine

01:45:04what they could look like.

01:45:06They probably have a lot of legs

01:45:08to facilitate their movement.

01:45:10They are not really big,

01:45:12but slender and extremely strong.

01:45:14Some kind of giant spiders,

01:45:16very muscular giants.

01:45:18The good news is that

01:45:20all this information is not confirmed.

01:45:22If we are very lucky and that

01:45:24the gravity there turns out to be

01:45:26just a little higher than that of the Earth,

01:45:28then of course it will be

01:45:30much easier to live there.

01:45:32We also know that Kepler-22b

01:45:34is about 15% closer to its star

01:45:36than we are to the Sun.

01:45:38If Kepler-22b existed

01:45:40in our solar system,

01:45:42it would be located somewhere

01:45:44between Jupiter and Venus.

01:45:46Does this mean that we are all going to burn?

01:45:48No. As I said earlier,

01:45:50the Kepler-22 star is rather cold,

01:45:52barely 5,600 degrees Celsius.

01:45:54This is why we can assume

01:45:56that the temperatures on Kepler-22b

01:45:58are about the same

01:46:00as those we have on Earth.

01:46:02In any case, if the planet rotates

01:46:04around its star in the same way

01:46:06that the Earth rotates around the Sun,

01:46:08which we do not really know.

01:46:10Kepler-22b can rotate around its star

01:46:12like Uranus, for example.

01:46:14What? You did not know

01:46:16that Uranus is lying on its side

01:46:18and that it also has rings?

01:46:20Yes, Uranus also has rings,

01:46:22like Saturn, but they are vertical.

01:46:24The universe is really a fascinating place.

01:46:26In short, if Kepler-22b

01:46:28is similar, then its climate

01:46:30will not be very hospitable,

01:46:32to put it nicely.

01:46:34Incredibly cold winters

01:46:36will be followed by boiling summers.

01:46:38And as for planets in synchronous rotation,

01:46:40we could live more or less comfortably

01:46:42on the narrow strip of land

01:46:44located between the two extreme hemispheres.

01:46:46Let's hope that this will not be the case

01:46:48and that the planet rotates normally.

01:46:50But everything is not so bad.

01:46:52Studies show

01:46:54that there may be an ocean

01:46:56on Kepler-22b.

01:46:58You already know that water is synonymous with life.

01:47:00But in this case,

01:47:02it is also a big advantage

01:47:04because a planet covered by an ocean

01:47:06always has more stable temperatures.

01:47:08The ocean absorbs a part of the heat

01:47:10and distributes it evenly on the planet.

01:47:12The hot parts cool down

01:47:14and the icy parts warm up.

01:47:16Besides,

01:47:18this is exactly what happened to the Earth

01:47:20billions of years ago.

01:47:22When our planet began to have

01:47:24its first small puddles of water,

01:47:26our beloved moon helped

01:47:28these puddles of water spread

01:47:30all over the planet.

01:47:32Thanks to this, the incandescent rock

01:47:34that was our Earth turned into

01:47:36a small puddle full of life.

01:47:38So if Kepler-22b has water

01:47:40but no atmosphere,

01:47:42scientists think that the average temperature

01:47:44there could be around

01:47:46minus 11 degrees Celsius.

01:47:48But if there is also an atmosphere

01:47:50similar to that of the Earth,

01:47:52then the temperature can reach 22 degrees Celsius,

01:47:54which would be ideal.

01:47:56And finally,

01:47:58a year there is equivalent to

01:48:00290 terrestrial days,

01:48:02or about 9 months.

01:48:04So, unfortunately,

01:48:06we would have to ignore

01:48:08this beautiful view of the moon.

01:48:10But the good news is that we would probably

01:48:12be able to see the sun

01:48:14as a small distant star.

01:48:16We could admire it in this night sky

01:48:18while still paying attention

01:48:20to these giant spiders.

01:48:22That's all we know for now.

01:48:24Unfortunately, it is quite difficult

01:48:26to explore such planets,

01:48:28so that there is still a lot of very important

01:48:30data that we do not know.

01:48:32For example, what kind of planet is it?

01:48:34Yes, we lack the most crucial

01:48:36information on Kepler-22b.

01:48:38We do not know if it is a

01:48:40telluric planet or not.

01:48:42And if this is not the case,

01:48:44then all the information mentioned above

01:48:46is useless.

01:48:48It may be a gas planet,

01:48:50or a planet covered with gas

01:48:52with a solid nucleus like Neptune,

01:48:54or an aquatic world covered

01:48:56by a giant ocean.

01:48:58It would be better if it were an aquatic planet.

01:49:00We could build a kind of underwater city there.

01:49:02We could filter the water

01:49:04and eat fish.

01:49:06Until we evolve into an amphibious species.

01:49:08Would it be considered an evolution

01:49:10if we went back to our origins?

01:49:12Anyway, scientists

01:49:14think that Kepler-22b

01:49:16could turn out to be a planet similar

01:49:18to Neptune.

01:49:20Some astronomers have even put the planet

01:49:22in the category of mini-Neptunes.

01:49:24Yes, it is a real planet category.

01:49:26But this has not yet been proven.

01:49:28And even if Kepler-22b

01:49:30turns out to be a telluric planet,

01:49:32we still do not know what the atmosphere

01:49:34over there looks like.

01:49:36Or even if there is one.

01:49:38And if it turns out to be like that of Venus,

01:49:40it would be extremely toxic.

01:49:42It would then be necessary to dig deeply

01:49:44underground to survive

01:49:46in one way or another on this planet.

01:49:48And it would also be necessary to find a source of heat

01:49:50because it is rather cold underground.

01:49:52There are many possibilities

01:49:54with Kepler-22b.

01:49:56So far, we do not have a clear answer.

01:49:58But let's hope that scientists

01:50:00will find them before we

01:50:02embark the first people in shuttles

01:50:04and send them on the conquest of Kepler-22b.

01:50:06It would be embarrassing

01:50:08if it turned out to be a gas planet

01:50:10or an ultra-toxic atmosphere.

01:50:26You must be happy to have brought

01:50:28your thermal suit, right?

01:50:30To leave the space ship,

01:50:32the Earth will need the help

01:50:34of a gravity machine

01:50:36because the gravity on Pluto

01:50:38is barely a fifteenth

01:50:40of that of the Earth.

01:50:42Gravity is the force

01:50:44that pulls us to the ground.

01:50:46The more the mass of a space body is weak,

01:50:48the more the force of gravity

01:50:50will pull us to the ground.

01:50:52The more the force of gravity

01:50:54pulls us to the ground,

01:50:56the more the mass of a space body is weak,

01:50:58the more its gravity is weak.

01:51:00So on Pluto,

01:51:02you can't do any sport

01:51:04that involves running.

01:51:06If you did,

01:51:08you would probably fly away.

01:51:10But you can try to lift elephants.

01:51:12After all,

01:51:14you can't do it on Earth.

01:51:16On Pluto,

01:51:18lifting an elephant

01:51:20of 900 kg

01:51:22The atmosphere of this planet

01:51:24is dark and cold.

01:51:26You could feel overwhelmed

01:51:28by the gigantic size of the planet.

01:51:30It's not for nothing that we call it

01:51:32the ice giant.

01:51:34Maybe today you would like

01:51:36to do winter sports?

01:51:38To say that Neptune lives in perpetual winter

01:51:40is an euphemism.

01:51:42The average temperature on the planet

01:51:44is about minus 225 degrees Celsius.

01:51:46But gravity here is only

01:51:4810% stronger than that of the Earth,

01:51:50so it makes no difference.

01:51:52This world has no solid surface,

01:51:54so you won't be able to leave the spaceship.

01:51:56Is it a ice hockey rink

01:51:58that I see?

01:52:00Take your ice skates and your stick

01:52:02and get ready to play

01:52:04against the other passengers.

01:52:06What would you say

01:52:08about a quick stop on Uranus?

01:52:10It is another ice giant

01:52:12and the gravity here is 90%

01:52:14of that of the Earth.

01:52:16You could pump a few times

01:52:18and the ice surface of the planet

01:52:20is composed of water, methane

01:52:22and ammonia in liquid form.

01:52:24There is no solid ground on which to walk.

01:52:26But if you found a way out,

01:52:28you would feel lighter than on Earth.

01:52:32If you weighed 45 kilos at home,

01:52:34you would weigh 40 kilos here.

01:52:36We could call it a Uranian regime.

01:52:38When you approach Saturn,

01:52:40be careful of its rings,

01:52:42which are not really rings.

01:52:44They are made up of pieces of asteroids

01:52:46and meteors that fly around the planet.

01:52:48The mass of Saturn is so large

01:52:50that it attracts many other objects

01:52:52on its orbit.

01:52:54And right now, you are one of them.

01:52:56It is time to be creative with your training.

01:52:58Did you plan to experiment

01:53:00with parachuting?

01:53:02If you fall free in the atmosphere of Saturn,

01:53:04you will reach a speed

01:53:06of 48 km per second.

01:53:08Don't forget to open your parachute.

01:53:10If you think about it,

01:53:12you won't be able to touch the ground anyway.

01:53:14The mass of Saturn is pure gas.

01:53:16A little funny anecdote.

01:53:18At one time, Saturn prevented

01:53:20the formation of the 10th planet

01:53:22of the solar system.

01:53:24The debris of the planet,

01:53:26which is now partly Saturn's rings,

01:53:28could have melted to form a planet.

01:53:30But they were attracted to Saturn's orbit instead.

01:53:32You approach Europe,

01:53:34one of Jupiter's moons.

01:53:36Gravity here is so low

01:53:38that you feel weightless.

01:53:40Let's say there is a climbing wall over there.

01:53:42Normally, this sport requires

01:53:44a lot of physical strength.

01:53:46But here, you will only have to

01:53:48carry 13% of your weight.

01:53:50Your ascent to the top

01:53:52will be easy in these conditions.

01:53:54Entering the atmosphere of Jupiter,

01:53:56you will feel like you are

01:53:58inside a cloud.

01:54:00Do you see this red spot in the corner

01:54:02at the bottom left?

01:54:04It is a storm twice the size of Earth

01:54:06that has been raging for hundreds of years.

01:54:08To have a little fun,

01:54:10I will count to 100.

01:54:12Ready, go!

01:54:14Gravity here is very strong.

01:54:16It is 2.5 times more powerful

01:54:18than gravity on Earth.

01:54:20So you will probably be exhausted

01:54:22after 30 seconds.

01:54:24Too bad!

01:54:26Oh oh!

01:54:28Attention to the passengers of the ship!

01:54:30Please fasten your seatbelts.

01:54:32You could have strong turbulence.

01:54:34To go from Jupiter to Mars,

01:54:36you will have to cross an asteroid belt.

01:54:38If you feel like doing something, relax.

01:54:40There is a distance of 480,000 km

01:54:42between the asteroids.

01:54:44Let's stop on Ceres,

01:54:46the only dwarf planet of the asteroid belt.

01:54:48Here, gravity will make you feel

01:54:50very strong.

01:54:52What would you say to train

01:54:54to throw a tree trunk?

01:54:56Kabers are heavy logs

01:54:58that can be up to 6 meters long.

01:55:00The goal is to throw them

01:55:02as far as possible.

01:55:04Here, an 80 kg pole seems to weigh 2,

01:55:06Are you ready for the competition

01:55:08to throw a tree trunk on Ceres?

01:55:10Woohoo!

01:55:12Finally, Mars!

01:55:14Do you remember the supports on the hands

01:55:16that you always wanted to try?

01:55:18Here is where to do them.

01:55:20The gravity of Mars is about 2.5 times

01:55:22weaker than that of Earth.

01:55:24This means that you will probably be able

01:55:26to lift the weight of your own body

01:55:28without any difficulty.

01:55:30As people want to terraform Mars,

01:55:32opening a gym here is not a bad idea,

01:55:34is it?

01:55:36To all passengers and crew members,

01:55:38we start our descent towards Phobos.

01:55:40It is one of the moons of Mars.

01:55:42The gravity here is incredibly weak.

01:55:44If you have always dreamed of having

01:55:46superhuman strength,

01:55:48this is the ideal place for you.

01:55:50You can train here by doing,

01:55:52for example, artistic gymnastics.

01:55:54Start by making the wheel,

01:55:56then move on to figures executed in the air.

01:55:58On Phobos, you can do triple back flip

01:56:00in a blink of an eye.

01:56:02Ah, look!

01:56:04The Earth is about to appear on the horizon.

01:56:06From here, it is majestic.

01:56:08But we are not going to stop there.

01:56:10Instead, we will visit the sister of the Earth,

01:56:12Venus.

01:56:14She has almost the same mass as the Earth,

01:56:16which means that they have a similar gravity.

01:56:18Earthlings cannot survive

01:56:20on the surface of Venus

01:56:22because of the large amount of ammonia

01:56:24in its atmosphere.

01:56:26But let's imagine that you can practice

01:56:28sports in the open air here.

01:56:30For this, you have to cover yourself

01:56:32with a huge ball

01:56:34and constantly bump into other players.

01:56:36People play this game on Earth.

01:56:38On Venus, with its slightly lower gravity,

01:56:40it could be a little easier.

01:56:42But still,

01:56:44you have to take into account

01:56:46that you will have a ball of 10 kilos like a vest.

01:56:48A bit like a hamster on Earth.

01:56:50Not to mention that your outfit will limit

01:56:52your arms and legs.

01:56:54It will be a challenge, but it seems fun to me.

01:56:56We continue.

01:56:58If you land on the sunny side of Mercury,

01:57:00you will know temperatures

01:57:02of 426 degrees Celsius.

01:57:04If you feel tired

01:57:06after your training session in space,

01:57:08a moist and relaxing sauna

01:57:10will do you great good.

01:57:12You will feel like a whole new person

01:57:14when you arrive on the next planet.

01:57:16We will fly as close as possible to the sun

01:57:18so that you can feel its gravity.

01:57:20The mass of the sun is huge.

01:57:22It is more than

01:57:24333,000 times the mass of the Earth.

01:57:26And gravity is extremely powerful here.

01:57:28You would have a hard time lifting

01:57:30an object as light as a bottle of water

01:57:32if it was possible to walk

01:57:34on the surface of the sun.

01:57:36Too hot, you say?

01:57:38Well, I guess it's much cooler

01:57:40if you come back at night.

01:57:42Haha, I'm kidding.

01:57:44On the way back,

01:57:46we will stop on the moon,

01:57:48the natural satellite of our Earth.

01:57:50Walking on the surface of the moon is like jumping.

01:57:52You can jump up to 10 meters,

01:57:54or try parkour.

01:57:56If you play basketball,

01:57:58scoring a point will be very difficult.

01:58:00But you can jump higher than the basket

01:58:02and do a spectacular slam dunk.

01:58:04And why not baseball?

01:58:06If you throw the ball up,

01:58:08you will probably never see it again.

01:58:10Finally, we land on Earth.

01:58:12Sorry to disappoint you,

01:58:14but you won't come back with superhuman strength.

01:58:16Even when you lifted an elephant,

01:58:18gravity helped you a lot.

01:58:20But it was a good trip,

01:58:22don't you think?

01:58:53Don't forget to fasten your seatbelt.

01:58:55Our first destination is a gas giant

01:58:57called TRES-2b.

01:58:59It is 750 light years away from us.

01:59:01If we used an ordinary space ship,

01:59:03it would take us about 10 million years

01:59:05to get there.

01:59:07TRES-2b is orbiting a yellow dwarf,

01:59:09a star similar to our sun.

01:59:11And it is about 1.5 times the weight of Jupiter.

01:59:13So, how do we get there?

01:59:15Well, it's easy.

01:59:17We take a plane,

01:59:19and it's about 1.5 times the weight of Jupiter.

01:59:21So, what's so special about it?

01:59:23Well, if you are afraid of the dark,

01:59:25you certainly won't want to visit this place.

01:59:27It is the planet of the eternal night,

01:59:29the darkest of all the planets

01:59:31that we knew.

01:59:33But it is not that far from its star.

01:59:35So, how is it done?

01:59:37The fact is that the surface of TRES-2b

01:59:39reflects the light even more badly

01:59:41than coal.

01:59:43Because of this,

01:59:45it looks like there is

01:59:47no light at all.

01:59:49If you flew over the surface of this planet,

01:59:51it would be as if you were moving

01:59:53with a bandeau on your eyes.

01:59:55But wait!

01:59:57In fact, there is light.

01:59:59A strange glow of a deep red

02:00:01surrounds the surface of the planet.

02:00:03This glow comes from its burning atmosphere,

02:00:05which makes TRES-2b

02:00:07an extremely hot planet.

02:00:09The air there is even hotter than lava.

02:00:11Terrifying, isn't it?

02:00:13But you haven't seen anything yet.

02:00:15We are now going to go

02:00:17to an even more horrible place

02:00:19than this one.

02:00:21NASA didn't exaggerate

02:00:23when it had to give it a nickname.

02:00:25This time,

02:00:27it's not just one planet,

02:00:29but three at the same time.

02:00:31They are also quite far away,

02:00:33at 2,300 light-years from the Sun.

02:00:35It would take us about 35 million years

02:00:37to reach them by shuttle.

02:00:39All these planets are located

02:00:41in the constellation of the Virgo

02:00:43which is much lighter than Earth.

02:00:45These three exoplanets

02:00:47are called Poltergeist,

02:00:49Droger and Phobetor.

02:00:51Nice name, isn't it?

02:00:53It's because each of these planets

02:00:55is about to become a ghost.

02:00:57Their particularity is that they

02:00:59do not revolve around a star,

02:01:01but around a pulsar.

02:01:03Pulsars are neutron stars

02:01:05whose magnetic field

02:01:07is extremely powerful.

02:01:09To put it simply,

02:01:11when a star explodes,

02:01:13it emits a very fast periodic signal.

02:01:15Indeed, the star rotates

02:01:17at an unimaginable speed,

02:01:19several thousand rotations per second.

02:01:21At the same time,

02:01:23it emits a strong electromagnetic radiation

02:01:25that affects everything

02:01:27around it.

02:01:29You have probably already guessed

02:01:31what is happening to our zombie planets.

02:01:33They are slowly and gradually destroyed

02:01:35under the gigantic influence

02:01:37of these radiations.

02:01:39One day, they will disappear

02:01:41without a trace.

02:01:43Ghost planets orbiting a living dead?

02:01:45Yes, the term

02:01:47zombie world is quite appropriate.

02:01:49It is not surprising

02:01:51that the scientists nicknamed this pulsar

02:01:53the Lich.

02:01:55Its official name is, for its part, very long.

02:01:57At least, we can say that it shrinks its elbows

02:01:59before disappearing forever.

02:02:01This planet also has a super long name.

02:02:03So, a little patience.

02:02:05HD-189733

02:02:07HD-189733

02:02:09B

02:02:11This gas giant is 65 light years away from us.

02:02:13It would take us about

02:02:15a million years to get there

02:02:17aboard our space ship.

02:02:19HD, uh ...

02:02:21The mass of this planet is slightly larger

02:02:23than that of Jupiter,

02:02:25and it revolves around its star,

02:02:27an orange dwarf, all alone.

02:02:29At first glance, it will look like

02:02:31everything there is nice.

02:02:33A pretty blue color and spirals on the surface.

02:02:35It looks like a summer sky,

02:02:37or like the scum of the waves in the ocean,

02:02:39don't you think?

02:02:41But the appearances are really misleading,

02:02:43my friend.

02:02:45This planet owes its pretty cobalt blue color

02:02:47to its misty and burning atmosphere.

02:02:49It contains grains of silicate

02:02:51that condense under the effect of heat.

02:02:53In other words,

02:02:55the clouds of this planet are raining ...

02:02:57green.

02:02:59Yes, it's raining pieces of burning green.

02:03:01And if that wasn't enough,

02:03:03Jupiter is on the surface

02:03:05and it moves at a speed of

02:03:078690 km per second.

02:03:09Just to compare,

02:03:11the fastest wind ever recorded on Earth

02:03:13had a speed of 408 km per hour,

02:03:15which is about 20 times less strong.

02:03:17And because of this,

02:03:19hundreds of thousands of green splashes

02:03:21are at all times projected horizontally

02:03:23over the entire surface of the planet

02:03:25at a dizzying speed.

02:03:27Too bad for the one who would try to land here.

02:03:29But this is not the only example

02:03:31of strange rain in our universe.

02:03:33For example,

02:03:35it rains molten iron

02:03:37on the planet Dimidium,

02:03:39or let's take what we call

02:03:41the carbon planets.

02:03:43Their existence has not yet been proven,

02:03:45but if they really exist,

02:03:47they would be covered by thousands

02:03:49of black and toxic clouds.

02:03:51And it would rain hydrocarbons

02:03:53as well as burning liquid asphalt.

02:03:55And all these raindrops would explode

02:03:57in a matter of seconds.

02:03:59Nothing special, right?

02:04:01The next planet, however,

02:04:03is really very, very strange.

02:04:05It was not content to rotate

02:04:07around its star.

02:04:09It lived inside.

02:04:11This cosmic miracle

02:04:13is called KOI 55b

02:04:15or Kepler 70b.

02:04:17This planet is very far from us,

02:04:194000 light years away.

02:04:21It would take about 70 million years

02:04:23for our spaceship to take us there.

02:04:25KOI 55b is much lighter than Earth

02:04:27and makes a complete revolution

02:04:29around its star in just 2 hours.

02:04:31A long time ago,

02:04:33it was an ordinary planet

02:04:35similar to Earth and the size of Jupiter.

02:04:37It was peacefully revolving

02:04:39around its red dwarf star KOI 55.

02:04:41But everything changed

02:04:43about 700 million years ago.

02:04:45You may have heard that

02:04:47in a few billion years,

02:04:49our sun would begin to grow

02:04:51and become huge,

02:04:53but it's the fate of red dwarfs.

02:04:55Sooner or later, they grow

02:04:57and become incredibly hot

02:04:59blue giants.

02:05:01And that's exactly what happened

02:05:03with KOI 55.

02:05:05This star began to grow in size

02:05:07and to warm up,

02:05:09gradually turning into a white blue giant.

02:05:11It was ready to devour

02:05:13its closest planets.

02:05:15But KOI 55b

02:05:17didn't care.

02:05:19When the star reached it,

02:05:21the planet simply settled

02:05:23inside.

02:05:25In addition, after a while,

02:05:27it even left its star

02:05:29simply placing itself on a new orbit.

02:05:31How is this possible?

02:05:33The time spent inside its star

02:05:35transformed KOI 55b

02:05:37into a big white hot rock.

02:05:39It's one of the hottest planets

02:05:41we've discovered so far.

02:05:43The temperature reaches

02:05:456,650°C.

02:05:47It's hotter than our sun,

02:05:49which is, I remind you,

02:05:51a real star.

02:05:53And inexplicably,

02:05:55its existence continues as if nothing happened.

02:05:57Unfortunately, sooner or later,

02:05:59the planet will eventually disappear.

02:06:01It evaporates slowly

02:06:03due to its incandescent atmosphere.

02:06:05But still, it will have survived

02:06:07its journey through the star.

02:06:09Which is far from being an ordinary feat,

02:06:11unless we can say.

02:06:13What a willpower!

02:06:15However, not all planets are as lucky.

02:06:17Some of them are gradually destroyed

02:06:19by their star.

02:06:21This last planet is sadly

02:06:23solitary.

02:06:25It's 870 light years away from us.

02:06:27Our journey by ship would take

02:06:29about 25 million years.

02:06:31The mass of this planet is about

02:06:331.5 times larger than Jupiter's.

02:06:35It's a place as sad as dark.

02:06:37This condemned gas giant,

02:06:39which looks a lot like Jupiter,

02:06:41revolves around its star

02:06:43all alone.

02:06:45It is located so close to its star

02:06:47that its orbital period lasts only one day.

02:06:49Of course, because of this proximity,

02:06:51the star gradually absorbs

02:06:53WASP-12b.

02:06:55Its intense heat slowly destroys

02:06:57and devours the planet's atmosphere.

02:06:59It only has about 10 million years left.

02:07:01But here's something

02:07:03even more interesting.

02:07:05Because of a rare phenomenon of stretching,

02:07:07WASP-12b now has the shape of an egg.

02:07:09It doesn't even look like

02:07:11a real planet anymore.

02:07:13It's also very hot.

02:07:15The surface temperature of this gas giant

02:07:17is 2,204 °C.

02:07:19In addition, a spectrographer

02:07:21of cosmic origins,

02:07:23or SOC in abbreviated,

02:07:25discovered that the planet exchanged

02:07:27matter with its star.

02:07:29They are so close to each other

02:07:31that part of their chemical elements

02:07:33pass through them.

02:07:35It's a common phenomenon

02:07:37in very close binary star systems.

02:07:39But it's the first time scientists

02:07:41have discovered a truly unique system.

02:07:43Frankly, if I was guaranteed

02:07:45total security,

02:07:47I would be delighted to go

02:07:49to some of these planets.

02:07:51And you? Let me know in the comments.

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