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00:00Mars. The god of war and the source of man's science fictional demise. It has fired our imagination for thousands of years. We know the dry, barren planet was once flowing with vast reservoirs of water, the sky thick and filled with clouds, and the tantalizing possibility of life. It is the only other place in our solar system that man might one day call home.
00:30NASA Jet Propulsion Laboratory, California Institute of Technology
01:00We earthlings have fired numerous probes and satellites towards the red planet, an invasion
01:11of sorts not for conquest but for knowledge.
01:15What happened to Mars?
01:17Is there or has there ever been life on the planet?
01:20A fundamental question that needs to be answered is life as we know it on Earth, even the simplest
01:28type of microbial life unique.
01:31If we were to go to Mars and we were to find evidence of early microbial life or maybe even
01:37present life that somehow survived in the near surface, would it be the same as the early
01:43life that developed on Earth?
01:45That's a very fundamental question.
01:47Does life emerge generally in planets where the conditions for life are favorable if we
01:53find out that they were favorable on Mars?
01:56Or might life take its own unique path in different environments and turn out differently?
02:04We have bombarded Mars with satellites and landers but there have been more failures than successes.
02:10The Soviets established two Mars orbiters while NASA landed two Viking landers carrying complex
02:16analytical laboratories and searched for signs of microbial life.
02:20Their findings were inconclusive.
02:28Further missions to Mars still had a high mortality rate but the successes were outstanding with
02:33robotic probes operating for years beyond their initial missions.
02:41In fact, Mars is a planet occupied solely by robots on the surface and satellites peering
02:46down from above.
02:52All these instruments perform admirably in their specified fields of endeavor, giving us
02:57a much clearer picture of the planet and its history.
03:00The science was following the water, what happened to it and where it is now.
03:08Thanks to the specific instrumentation on board the mission, we were able to tell us what
03:14kind of ice did we find.
03:16And the result is that there is a mix of CO2 ice or carbon dioxide ice and water ice.
03:23And it's very important to characterize it, especially for the water ice or frozen water,
03:28because one of the main objectives of any mission to Mars is to trace the water on Mars in every
03:34form, liquid if possible, solid water vapor.
03:39So it's very important to study the ice because it's one of the reservoirs of water on the planet.
03:45The science was conclusive.
03:47There was water on Mars.
03:49There were ancient lakes and rivers, even an ocean.
03:52We needed to learn more.
03:56With the advancement of analytical technology, computer power and robotics, a new rover was
04:01constructed.
04:02Big, complex and heavy, it required a new way to land on Mars safely.
04:09Engineers came up with a system that couldn't be fully tested here on Earth.
04:16It required a lot of things to happen correctly on time and in order.
04:21This was the Skycrane and the rover Curiosity was the first to try it out.
04:26A controlled re-entry with heat shield, aerobraking with a parachute, all pretty standard.
04:33Then a rocket-powered Skycrane drops from the aeroshell and gently descends toward the surface,
04:38spooling out the rover below on cables.
04:41The rover touches down, cuts the cables, and releases the Skycrane to fly off and crash
04:47harmlessly.
04:49The Curiosity rover has been an astounding success, traversing the terrain for over ten years,
04:54taking samples, drilling and studying rock formations, zapping samples with a powerful
04:59laser and photographing its progress.
05:02Now in the belly of that rover is an instrument called SAM.
05:07It's an instrument suite that has a couple different instruments in it that allow us to
05:10look at different types of gases.
05:13It helps us understand the chemical composition of the atmosphere and the end of minerals that
05:19might be found in the rocks and the soils on the surface.
05:23In particular, it helps us identify organic molecules that might be present.
05:28So the sorts of evidence we're looking for, sorts of signatures of past life that we would
05:32be looking for would be signatures of microbial life.
05:35So not realistically looking for dinosaur bones and that kind of thing.
05:39If life ever existed on Mars, we expect it to have been microbial microorganisms.
05:53Orbiters including Mars Odyssey and Mars Express have been hunting down life as well from orbit.
06:19After ten years of mission, we have achieved a global view of Mars.
06:24And then we know at every location on the surface if you find some special minerals or not.
06:29So we have really the global view that tells us the history of Mars.
06:34Mars Express has for the first time detected methane.
06:38And also the concentration in the atmosphere varies from a place to another, from a season
06:43to another.
06:45This discovery has been very debated in the scientific community because, in fact, methane
06:51should not be there because it's being destroyed in the atmosphere by the ultra-electric radiation.
06:57So if methane is there, there must be a source of methane.
07:01And for the time being, the origin of this source is largely unknown.
07:06However, with curiosity prowling around Gale Crater, it too detected seasonal methane.
07:13Now methane has been found previously in the Martian atmosphere by both Earth-based telescopes
07:19and space-borne orbiters.
07:21But this is the first time that we've actually seen a sharp increase and decrease in the abundance
07:25of methane in the atmosphere in Gale Crater.
07:28What this really means is that present-day Mars is an active environment.
07:33The big question is, what is the origin of this methane now being released?
07:39The two principal areas are, first, by analogy with the Earth, it could be released and produced
07:45initially primarily by biology.
07:48This would be microbial activity, acting on certain chemicals below the surface, and then
07:53producing methane as a byproduct.
07:55But, of course, we can't state with certitude that it is biologically produced.
08:02And so we also consider geochemical mechanisms in which carbon dioxide is actually combining
08:10with water and producing methane under very high temperatures and pressures.
08:15And that methane can then be released in the atmosphere separately.
08:17Now, at this point, we don't have enough evidence to tell us whether or not the organics we're
08:24finding are biological or non-biological in origin.
08:28There are several viable non-biological explanations, including this organic material could have come
08:33down from space, from meteorites or comets, or organics can be formed by geological reactions
08:39in the rock itself.
08:41Now what's exciting about this discovery is it gives us new hope in the search for chemical
08:46evidence of life.
08:47We found the organic material.
08:48Now the next step is trying to figure out what its origin is.
08:51The main engine start, ignition, and liftoff of the Atlas V with MAVEN, looking for clues
08:59about the evolution of Mars through its atmosphere.
09:04The latest NASA orbiter mission is MAVEN.
09:07Launched in November 2013, it made orbit 10 months later.
09:17MAVEN is the Mars Atmosphere and Volatile Evolution mission.
09:21Our goal is to study the role that loss to space has played in the history of the atmosphere.
09:27Where did the water go?
09:28Where did the CO2 go from the early planet?
09:31These are important questions to understand how Mars went from an early, warm, wet environment
09:39to the cold, dry environment we see today.
09:42There's evidence of water flowing on Mars at one point in time, perhaps even oceans on Mars.
09:51And what happened that it's so barren at this point in time?
09:55And a key part of that is the atmosphere, and it's a much thinner atmosphere than what scientists
10:01believe it was at one point in time.
10:03So the stripping away of that upper atmosphere, that's what MAVEN is going after, the climate
10:08change at Mars.
10:10One of these processes is called sputtering, where atoms are knocked away from the atmosphere
10:18due to impacts from energetic particles.
10:21The Sun constantly emits high-energy photons.
10:24When these enter a planet's atmosphere, it can crash into a molecule, knocking loose an
10:28electron and turning it into an ion.
10:32When this happens, in the presence of a magnetic field, the ions are captured and spin around
10:36the field.
10:37Conveniently, the Sun generates a giant magnetic field that is carried by the solar wind.
10:44As the magnetic field sweeps past the planet, these ions are carried away.
10:50Depending on where they form, other ions will not be carried away, but will hit the top of
10:55the atmosphere.
10:56These ions crash into other molecules and fling atoms everywhere.
11:01Some of these atoms can be knocked or sputtered into space, causing atmospheric loss.
11:05As this process continues over billions of years, Mars' atmosphere has disappeared and,
11:16along with it, the water.
11:18How much water has Mars lost this way?
11:22We used the world's three major telescopes for infrared astronomy.
11:29From the ground, we could actually take a snapshot of the whole hemisphere of the planet on a single
11:34night.
11:35Water naturally carries a heavy isotope of hydrogen, deuterium, which remains trapped in
11:40the water cycle, while normal hydrogen is lost to space.
11:44Detecting the amount of deuterium enrichment tells us how much water has been lost.
11:51Now we know that Mars' water is much more enriched than terrestrial ocean water in the heavy
11:56form of water, the deuterated form.
11:59Immediately, that permits us to estimate the amount of water Mars has lost since it was
12:03young.
12:04So, in the ancient past, we have some indications that water was flowing on the surface, but
12:18how much water was there?
12:19We're talking about oceans, we're talking about small rivers, little rain.
12:24So these definitions of how much water was on the planet was very undefined.
12:27A major question has been, how much water did Mars actually have when it was young, and
12:34how did it lose that water?
12:35The findings indicate that only 13% of an ancient ocean remains on the planet today, now stored
12:41in the polar ice caps.
12:4387% of this ocean has been lost to space.
12:48This means that early Mars would have looked much different than it does today, with a significant
12:53portion of its surface covered by water.
12:56So the really interesting question is, could it form a sea or an ocean?
13:00And indeed, it would.
13:02In the Northern Plains, which is a relatively flat region but depressed from the rest of
13:05the planet, it would form an ocean that was approximately 20% of the planet's surface area.
13:13So that is a respectable ocean.
13:16This ocean had a maximum depth of around 5,000 feet, or around one mile deep.
13:20It's deep, not as deep as the deepest points of our oceans, but comparable to the average
13:25death of the Mediterranean Sea.
13:28By combining Martian topography with the new estimate for water loss, the researchers
13:33were able to simulate Mars' ancient ocean and its escape to space.
13:38As Mars lost its atmosphere over billions of years, it lost the pressure and heat needed
13:43to keep water liquid, causing the ocean to shrink and recede northward.
13:48The remaining water eventually condensed and froze over the North and South Poles, giving
13:53Mars the ice caps that we see today.
13:55We now know that Mars was wet for a much longer time than we thought before.
14:03Curiosity shows it was wet for one and a half billion years, already much longer than the
14:08period of time needed for life to develop on Earth.
14:11And now we see that Mars must have been wet for a period even longer.
14:15It's fascinating that we can learn so much about 4.5 billion years ago, what measurements
14:20are taken right now.
14:21And ultimately we can conclude this idea of an ocean covering 20% of the planet, which
14:26opens the idea of habitability and the evolution of life on the planet.
14:32Building on this knowledge, scientists are developing the next series of robotic probes to be sent
14:37to Mars in the coming years. This time, NASA is building on its successes, utilizing hardware
14:44and systems that they know will work.
14:47We've been to Mars before with the JPL Lockheed Martin team. We've been to the surface of Mars
14:53before successfully with Phoenix. We know how to operate the arm. The surface operations
14:59are much, much simpler than Phoenix. We're putting two instruments on the surface and then
15:03we're leaving them there with no ground-in-the-loop interaction, repetitive weekly uplink-downlink
15:10sessions. We're just made to do this mission.
15:14The InSight mission is a geophysical mission to Mars. It's going to go to Mars and take its
15:19vital signs. It's going to take its heartbeat, the seismic activity of the planet.
15:24So we're going to be doing that using a seismometer, a very high-precision seismometer, using techniques
15:30that have been well-developed on Earth to get the understanding of the crust, mantle and
15:35core and sort of the relationship between those. It's going to take its temperature by
15:39measuring the thermal gradient of the surface, which tells how much heat is coming out.
15:42We also have a heat flow probe. We call it HP cubed. And what that does is it's going
15:47to basically take the temperature of Mars and from that it'll be able to understand what
15:51the thermal flux is over the course of a full Martian year. And it's going to sort of measure
15:56its reflexes by looking at how the rotation wobbles with the tile effects of the sun.
16:03Our final experiment is called RISE. And that's going to be looking at the, basically the wobble
16:09of Mars to help understand what the core size may be in composition.
16:17The European Space Agency is also well along with ExoMars, a rover with advanced drilling
16:22capability due to be launched by 2018. Its principal goal, to drill down deep in search of microorganisms.
16:37What is new with ExoMars, with the rover in particular, is what we call the mobility. Mobility not
16:43only horizontal, but also vertical. And this is a peculiar thing that we have on board ExoMars mission.
16:49So we will be able to sample material from below the surface. That is quite important to understand
16:56if there is any sign of past life activity on Mars. We will be looking for the first time in the third
17:03dimension. The third dimension being depth. And we think that is where we have the highest chance
17:10of making an interesting discovery regarding the presence of organic molecules in Mars.
17:26It's a whole planet out there with a complicated history. It's that history is a story that's stored
17:33in the rocks. And our job is to figure out that story. And what that story of that planet tells us about
17:39this planet that we live on. So where Curiosity takes rocks and grinds them up into powder and looks
17:45at their bulk constituents, what this mission would need to do is be able to look in a microscopic level
17:51and examine the rocks for these very tiny and detailed messages that they would be sending to us
17:57about the past life that could have lived there. This that I'm holding up here is a classic biosignature
18:03from the earth. It's a fossil. We're not actually expecting to see a fossil of shells or other
18:08components. But what we want to be able to see are with this instrumentation are the fine scale layering
18:15that one might see in a rock in which we can see dark and light toned layers. And those dark and light
18:21tone layers are telling a story.
18:30When will NASA send astronauts to Mars?
18:33Five, four, three, two, one.
18:38And liftoff at dawn. The dawn of Orion and a new era of American space exploration.
18:45The first test flight of the Orion crew capsule is complete. The hardware and systems are ready
18:53for mass production. The components, the engineering, the manufacturing are all underway,
18:58with NASA looking back to what worked in the past and utilizing it for the future.
19:02The solid rocket booster technology straight from the space shuttle has been extended and tested.
19:19NASA's new Space Launch System, or SLS, is coming closer to fruition, reusing the space shuttle's main
19:26engines as the new system's workhorses, saving billions of dollars and years in research and development.
19:32NASA's new Space Launch System, or SLS, is coming closer to the future.
19:36NASA's new Space Launch System, or SLS, is coming closer to the future.
19:38NASA's new Space Launch System, or SLS, is coming closer to the future.
20:00The Europeans are teaming up with NASA to provide
20:02the service model for Orion, allowing for long-duration, deep space flights.
20:15Autonomous Martian landing systems are well-advanced and being tested.
20:19Software and hardware are fully integrated for both manned and unmanned Martian landings.
20:24And when they get there…
20:26Desert RAT stands for Desert Research and Technology Studies. This is a group of engineers and scientists.
20:33We're looking to test out new concepts, procedures, equipment, like rover concepts,
20:39to see how they work in the field environment.
20:41So the team tests these technologies to make sure that in future human space flight missions,
20:45we'll be able to do science as best as we can.
20:49That's something that NASA's never done, two human rovers at the same time.
20:53So we're really trying to develop how do you use these assets at the same time,
20:58and interesting things that you might not think about are your communications.
21:02So you potentially have four astronauts talking all at the same time to a mission control or
21:06science communication background.
21:07It's just like running a real mission, say…
21:09Think about Apollo mission to the moon.
21:12You had the astronauts on the moon, you had the people mission controlled,
21:16but there was a science background you didn't hear about,
21:18but the astronauts were getting information from there.
21:22Arizona has a very good climate for these types of analog studies.
21:27You have pretty much open plains, and you have a lot of geological features
21:30that are analogous to places on the moon and on Mars.
21:33Long-term space voyages are being replicated on the ground and in orbit with the ISS.
21:48Surface habitats, power systems, food and oxygen supply manufacturing are also on the drawing board.
21:55The human flight component would like to see an experiment where resources on the surface of
22:03Mars from the rocks or the atmosphere could be used to generate fuel or other parts that would
22:10enable future exploration in cutting the ties, so to speak, to Earth.
22:15So you wouldn't necessarily have to bring everything with you.
22:17You can actually manufacture it on the planet, and that's a really exciting additional component
22:22that we've been exploring and analyzing in this work.
22:29NASA isn't the only one with its eye on this prize.
22:32ESA, and now the Indian Space Research Organization, have a spacecraft orbiting Mars,
22:38and they did it on their first attempt.
22:42Private enterprises are hard at work as well.
22:44Mars 500, Mars One, the Mars Society, Mars Foundation, and the Mars Initiative, to name a few.
22:51And they have volunteers lining up already for a one-way trip to Mars.
22:58It is inevitable that we will set foot on Mars in the very near future.
23:02We will stay and learn her secrets.
23:07Perhaps in the future we will be able to alter the atmospheric density through terraforming,
23:12and return Mars to the world that it once was,
23:15awash with oceans and rivers, clouds and rain.
23:20Maybe some of us could call it home.
23:23And again.
23:28Yes!
23:30That one dobrze nope.
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