Prêt à voir votre esprit époustouflé par des faits incroyablement cool sur la Terre ? Dans cette vidéo, nous plongeons dans les choses les plus folles concernant notre planète que vous ne connaissiez probablement pas, comme pourquoi la Terre bourdonne, comment nous fonçons à travers l'espace, et ce qui se passe réellement sous vos pieds. Ces faits sont si fascinants qu'ils pourraient bien faire fondre vos glaciers mentaux (ne vous inquiétez pas, c'est une bonne chose). Que vous soyez un passionné de sciences ou que vous aimiez simplement les anecdotes surprenantes à partager lors des soirées, cette vidéo est remplie de suffisamment de moments impressionnants pour vous tenir en haleine. Faites-nous confiance, vous ne regarderez plus jamais le sol sur lequel vous marchez de la même manière. Alors prenez un encas, installez-vous confortablement, et préparez-vous à voir la Terre comme vous ne l'avez jamais vue auparavant ! Animation créée par Sympa.
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https://www.eastnews.ru
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Musique par Epidemic Sound https://www.epidemicsound.com
Pour ne rien perdre de Sympa, abonnez-vous!: https://goo.gl/6E4Xna
----------------------------------------------------------------------------------------
Nos réseaux sociaux :
Facebook: https://www.facebook.com/sympasympacom/
Instagram: https://www.instagram.com/sympa.officiel/
Stock de fichiers (photos, vidéos et autres):
https://www.depositphotos.com
https://www.shutterstock.com
https://www.eastnews.ru
----------------------------------------------------------------------------------------
Si tu en veux encore plus, fais un tour ici:
http://sympa-sympa.com
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FunTranscript
00:00These cumulus clouds that you see in the sky
00:04weigh the equivalent of a Boeing 747 or a 100-elephant.
00:08If you doubt my words, let's do the math.
00:11Researchers have determined that the density of water inside a cumulus
00:15was about 0.5 g per cubic meter.
00:18Clouds take various shapes,
00:21but a cloud of this type usually has a cubic shape
00:24and a volume of 1 billion cubic meters.
00:27By multiplying this volume by the density,
00:29we get an impressive weight of more than 500 tons.
00:32And to answer your eventual curiosity,
00:35this giant remains suspended in the air
00:37because its density is lower than that of the atmosphere around it.
00:42Giraffes are 30 times more likely to be struck by lightning than you are.
00:46Between 1996 and 2010,
00:49five deadly cases involving giraffes struck by lightning were reported.
00:54But since there were about 140,000 of them in the world during this period,
00:58this mortality rate for 1,000 giraffes per year is relatively high.
01:03Lightning prefers to strike objects that are higher up,
01:06which makes giraffes easy targets.
01:08However, scientists think they may have learned to avoid this situation
01:13by seeking refuge in thunderstorms
01:15or by moving quickly to densely wooded areas.
01:19The oldest animals on Earth are glass sponges.
01:22Their life expectancy can reach 15,000 years.
01:25Scientists have discovered the oldest glass sponge in the Ross Sea,
01:29a region of Antarctica.
01:31In the East China Sea,
01:33other researchers have found the skeleton of a glass sponge
01:36that would have lived for about 11,000 years.
01:39These sponges could not have existed during the last ice age.
01:42They spend their entire existence fixed to solid surfaces,
01:46filtering water to feed on bacteria and plankton.
01:51Earth's rotation is slowing down,
01:54which leads to an extension of the days.
01:56A long time ago, a terrestrial day lasted only 19 hours,
01:59but this delay has extended to 24 hours,
02:02mainly due to the gravitational attraction of the Moon,
02:05which slows down our planet.
02:07Extreme events, such as earthquakes,
02:10can temporarily influence the speed of this rotation.
02:14A Chilean earthquake in 2010 probably slightly shortened our days.
02:19However, since 2020, the days tend to become longer again.
02:25Scientists still can't agree on whether the water is really wet.
02:31Some say that the water itself is not wet,
02:34but that it can make other objects wet by sticking to it.
02:37Others consider that water is wet because it is a liquid and contains humidity.
02:42Water can also seem wet when it cools the skin by evaporating.
02:46The humidity of an object depends on two forces.
02:49The cohesive forces that hold water droplets together,
02:52and the adhesive forces that allow water to stick to other surfaces.
02:56Water does not adhere well to impermeable tissues,
02:59which remain dry due to the domination of cohesive forces in this particular case.
03:03There is no world map that is perfectly precise,
03:06unless it is on a real scale.
03:08Indeed, our planet is spherical while the paper is flat.
03:12In the 16th century, Gerardus Mercator developed a cylindrical cartographic projection,
03:17still used today, and which bears his name.
03:20Although this projection is convenient for navigation,
03:23because the North is always at the top,
03:25it deforms the high and low parts of the map a lot.
03:28Thus, Groenland seems 14 times larger than it really is,
03:32while Alaska is represented by the size of Brazil.
03:36About 4 billion years ago,
03:38the Earth's atmosphere was radically different from the one we know today.
03:42But volcanoes have played a decisive role.
03:45Many volcanoes erupted across the globe,
03:48releasing carbon dioxide that filled the sky
03:51and constituted the essence of the atmosphere.
03:54Tiny primitive plants used this carbon dioxide
03:58to develop by photosynthesis, thus producing oxygen.
04:02One theory suggests that the steam released by volcanoes
04:06would be cooled and transformed into water, thus forming the oceans.
04:10It took about 2 billion years for oxygen to diffuse enough in the air
04:15to allow animal life.
04:18If, for some reason, you decided one day to stack all the bacteria
04:22and germs of the planet on top of each other,
04:25it would extend over 10 billion years of light.
04:28However, you would not perceive this thread,
04:31which would be about 75 times thinner than a human hair.
04:35If you wound this long chain of bacteria around our galaxy,
04:39the Milky Way, it would go around it more than 20,000 times.
04:43Shattering, isn't it?
04:46It turns out that there is rust on the Moon,
04:48and it is possible that it has traveled from Earth to get there.
04:52Rust usually forms in the presence of oxygen and water,
04:56two elements that the Moon has in negligible quantities.
04:59However, when this star crosses the magnetic tail of the Earth,
05:03terrestrial oxygen can reach it thanks to solar winds.
05:06This oxygen could then combine with low amounts of water and iron
05:11at the lunar surface to form rust.
05:16Even a small asteroid can take our planet out of its orbit.
05:20But don't worry, you probably won't notice any difference.
05:23The impact will depend on many factors,
05:26such as the resistance of the asteroid,
05:28its speed and the type of terrain it touches.
05:31In general, when space rocks hit the Earth,
05:34they disintegrate or turn into gas before reaching the ground.
05:38However, the larger ones,
05:40like the one that caused the extinction of the dinosaurs,
05:43can cause catastrophic phenomena,
05:45such as giant waves, earthquakes and climate change.
05:50The Earth is not as solid as a rock inside,
05:53but rather similar to soft clay
05:55due to the intense heat and pressure exerted under the surface.
05:59This flexibility allows the mantle to move slowly over millions of years,
06:03which explains the occurrence of earthquakes,
06:05volcanic eruptions and the drift of continents.
06:09During the last glacial period,
06:11huge glaciers covered the Earth's surface,
06:14exerting pressure on the malleable mantle below.
06:17This made the mantle slightly sink.
06:19When the glaciers melted, the mantle began to rise again,
06:22and the Earth began to rise.
06:24Even today, in regions such as Canada, Greenland and Scandinavia,
06:29the Earth continues to rise because of this phenomenon.
06:33Our planet is covered with cosmic dust.
06:36Every year, about 5,000 tons of this matter falls on Earth.
06:40These interstellar particles are smaller than a grain of sand
06:44and often thinner than a human hair.
06:46Scientists go into the depths of Antarctica,
06:49where there is little precipitation and where the snow is extremely pure,
06:53to detect these tiny particles.
06:55Most of this dust comes from comets.
07:00If you are a big introvert, Greenland is the perfect place for you.
07:04It is the least populated region in the world,
07:06with only 0.14 people per square kilometer.
07:10Wow, I've never really seen a tenth of a person.
07:13Anyway, most of Greenland is covered with ice,
07:17so that its inhabitants live mainly on the west coast.
07:21And for your information, it has been inhabited for more than 4,500 years,
07:25so it must not be so bad at the bottom.
07:29The ground on which you walk is actually recycled.
07:32First, hot and melted magma rises to the surface
07:35and cools down to become solid rock.
07:38Then, thanks to the tectonic forces, this rock is pushed up.
07:43Over time, the wind, the rain and other forces
07:46separate pieces of this rock.
07:49These pieces are taken and end up being deposited in layers.
07:53The latter are compressed, forming sedimentary rocks like sandstone.
07:57Sometimes, if these sedimentary rocks are pushed deeply under the surface of the Earth,
08:02the heat and pressure transform them into a new type of rock,
08:05called metamorphic rock.
08:07A long time ago, life on Earth could have been purple instead of green.
08:12Shildas Sarma, a molecular biologist at the University of Maryland,
08:16thinks that the first microbes used a special molecule
08:20to capture sunlight, which made them purple.
08:23Today, the plants of Greenland are green
08:26because they use chlorophyll to capture sunlight
08:29and transform it into energy.
08:31But before the existence of chlorophyll,
08:33it was retinal molecules that fulfilled this function.
08:36They absorbed the green light of the sun
08:39and reflected the red and purple light,
08:42which gave the microbes a purple hue.
08:44Like little grapes of grapes, really.