How the Universe Works - S08E02 - NASA's Journey to Mars
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00:00NASA has set its sights on Mars.
00:07Its goal is to send humans to the red planet in the next 20 years.
00:14Looking up at Mars in the sky, I really do feel like I'm looking at a place that someday there will be people walking around on it.
00:22It feels so much like Earth in so many ways.
00:26And it's a place that really captures my imagination as a result.
00:31It's the most Earth-like environment we see in our solar system.
00:34So we're not going to leave it alone. We're going to try to do this.
00:39But conquering our planetary neighbor is a tougher challenge than we ever thought possible.
00:45It's an isolated environment where a million things can go wrong, where there's absolutely no hope of rescue.
00:54There are so many hurdles to overcome for human exploration of Mars, and it makes it quite difficult.
00:59Sure, we can get there, but are we going to be in one piece?
01:03Sometimes it feels like Mars is designed to keep us away.
01:07Are we doomed to fail in this endeavor?
01:15NASA Jet Propulsion Laboratory, California
01:26The red planet. Earth's neighbor.
01:30And the destination of NASA's most ambitious mission to date.
01:36But this expedition will be harder than we ever thought possible.
01:41It hurts to think of how hard it is.
01:44It's the farthest a human being has ever been from the Earth.
01:47We've got to take every precaution.
01:50As NASA astronauts arrive at Mars, they will face a huge obstacle.
01:56Landing on the planet is a daunting task.
02:02In the past, Mars hasn't always rolled out the welcome mat.
02:07Mars is kind of like a graveyard for spacecraft.
02:10It's actually really hard to send something from Earth and land it on Mars.
02:15This is how the European Space Agency hoped its $250 million Schiaparelli lander would touch down in 2016.
02:26But the lander's systems got it wrong.
02:31The parachute detached early, sending the craft into freefall for 33 seconds.
02:40Schiaparelli smashed into the surface at 335 miles per hour,
02:46leaving a deep black scar in the Martian landscape.
02:51It turns out that Mars is actually a particularly difficult planet to land on.
02:55Even humanity's most brilliant engineers, we've got about a 50% success rate when it comes to landing on Mars.
03:02The red planet is littered with dead spacecraft that didn't nail the landing.
03:09And for NASA's first crew descent to Mars, the space agency must learn from these mistakes.
03:17But as the crew hurtles towards the surface, they're battling the same problem as all the landers that failed before.
03:28The Martian atmosphere is 100 times thinner than Earth's, so it can't provide the drag needed to slow a spacecraft down.
03:38So it's not like the Earth where you can have these big giant parachutes that gently glide you down to the surface.
03:47You can use some of the air, but it's hard.
03:53The red planet's thin atmosphere is a problem that has been billions of years in the making.
04:00Mars doesn't have a large atmosphere because it's constantly being peeled away due to the lack of protection of a magnetic field.
04:10The solar wind can strip away an atmosphere.
04:14On Earth, a liquid metal core creates a magnetic field, which shields the planet and helps maintain the atmosphere.
04:25But Mars is different.
04:294.5 billion years ago, Mars and Earth formed from dust and gas in space.
04:39Mars formed where building materials were scarce.
04:43Its growth was stunted.
04:47So Mars is much smaller than the Earth.
04:49It's a factor of 10 smaller than the Earth.
04:51And that factor of 10 in mass is important.
04:55All of that extra mass allows the inside of the Earth to stay warm and to have a core that's rotating, which generates a magnetic field.
05:054.5 billion years ago, the churning heart of Mars started to cool and solidify.
05:13With no hot core, there's no magnetic field being generated.
05:18All of the high-velocity charged particles coming from the sun pick away at the atmosphere and slowly tear it away.
05:28We know it's losing atmosphere every second due to the solar wind.
05:32So, you know, bye-bye atmosphere.
05:44With little Martian atmosphere to work with, NASA had to be creative to get its cruelest landers to the Martian surface.
05:57In 2012, the revolutionary Skycrane landed the Curiosity rover using parachutes and retro rockets.
06:08Previous missions have used both a parachute and something else, like a bouncy ball inflated around the spacecraft.
06:21I don't think a human crew is going to be too pleased if they're going to be bouncing onto the surface in an airbag rolling to a stop, right?
06:28To land people on Mars, NASA needs some new tricks.
06:34The 2020 rover will overcome the challenge with the Advanced Supersonic Parachute Inflation Research Experiment, ASPIRE.
06:46It will rapidly slow down the craft with the force of an airplane jet engine.
06:56This is fine for the rover. It's actually going to work no problem, but it's not going to work for people.
07:02A human lander will weigh far more than the 2,300-pound rover.
07:07Not even supersonic parachutes could land a crew safely on Mars.
07:14NASA will need a new plan.
07:18One idea is to use the thin Martian atmosphere in a unique way.
07:24There's an idea of coming in really fast, getting to the thick part of the atmosphere, and then going horizontal to the ground and gliding and losing your momentum that way.
07:37As the astronauts descend, they tilt the nose of the lander towards the Martian surface, aiming for the thickest part of the atmosphere close to the ground.
07:48Then they pull up at the last second, using friction from the atmosphere to slow the craft.
07:57The descent engines switch on for the final touchdown.
08:08Is this a crazy idea? I mean, yeah, it's a little bit weird. I don't know if we'd really think about it, doing something like this.
08:15But, I mean, you've got to think outside the box sometimes.
08:18Right now, NASA's plans for landing a craft on Mars are still on the drawing board.
08:24But even if they can get astronauts onto the surface, the thin atmosphere isn't done with them yet.
08:31It causes swirling dust storms that cover the planet's entire surface.
08:38Mars doesn't just have dust devils. It has dust hell.
08:42And these towering clouds have killed before.
08:48If NASA's astronauts arrive on Mars as planned in 2035, the settlers will find one of the Red Planet's biggest challenges is its dust.
09:07It's sticky. Basically, light from the sun can give this stuff a static charge, and then it clings to stuff.
09:15So it's not just a matter of, like, you know, standing on a doormat outside your space habitat and shaking yourself off.
09:22It's going to get in your space suit. It's going to coat your visor. It's going to cover your solar panels.
09:27If you get it in your lungs, it's not a good thing. We have to figure out how to clear this stuff out.
09:34300 feet. Minus 11.
09:37Through the 60s and 70s, Apollo astronauts walked on the moon.
09:44When they returned to their landing module, they brought moon dust back with them.
09:51The lunar dust clogged seals, caused equipment to overheat, resulted in false instrument readings, and even made astronauts sick.
10:01You don't want to be breathing in fine, dusty material.
10:05By itself, you can get things like silicosis.
10:08It's a, you know, almost basically a lung cancer that you can get just from breathing in the dust itself.
10:12You don't want to do that.
10:15The red planet is covered in sticky dust.
10:19And new research suggests it all came from one place.
10:27The Medusa Fossey Formation.
10:30A 600-mile long volcanic deposit formed 3 billion years ago.
10:35It was around half the size of the United States.
10:39But the Martian winds have eroded this structure and spread the dust across the entire planet.
10:48When the wind whips up this dust, it can have disastrous consequences.
10:54The real problem is just that all these fine particles get lofted into the atmosphere, and it takes a really long time for them to settle back out.
11:02And what the dust does is it just gets up in the sky and it sits there, and sits there, and sits there.
11:08As more material gets lifted into the atmosphere, it forms huge dust storms.
11:15The storms are so huge, they block out the sunlight and cool the Martian surface.
11:23Creating a temperature difference between the ground and atmosphere that causes winds to increase and the storms to grow.
11:34And NASA's Opportunity rover knows firsthand the dangers of being trapped in one.
11:41Opportunity was a NASA rover sent to Mars to hunt for signs of past water on the surface and potentially signs of past life.
11:54This is a rover that we really worked with so long, knew so well, and who had come up with so many amazing new results from Mars.
12:03June 2018. Opportunity was 15 years into its mission.
12:11When giant clouds of dust appeared on the horizon, NASA could only watch as the storm grew and grew.
12:21Once this dust storm coated the entire planet, it blocked the sun, and the sun was the source of Opportunity's power.
12:31Opportunity works using solar panels, and so it gradually got less and less and less electricity.
12:37For Opportunity, there was no escape.
12:42Lost in the darkness, Opportunity's power reserves slowly ran dry.
12:49The rover fell silent.
12:53We thought, well, maybe once the dust storm clears up, the panels can fire up again and we can get it back, but it just never woke up.
13:02If NASA astronauts do make it to Mars, the storms could damage more than the crew's power supply.
13:12When the storms begin to blow, they crackle with electricity.
13:18Just like you can create a static charge by rubbing your foot on the carpet or a balloon on your hair, this happens at large scale in these dust storms on Mars.
13:27The sand grains rub up against each other, and that creates the static charge.
13:32So you get these electrical flows that occur.
13:36Here on Earth, we see this in volcanic eruptions as the dust, the ash, burbling out of one of these huge eruptions.
13:42You'll see lightning discharges in those volcanic plumes from this same charge transfer.
13:48If you're in a place with a lot of electrostatic discharge, that means sparks are going to fly, which is really terrible for operating instruments.
13:56To survive on Mars, the settlers are going to need a protective shelter.
14:03The key word to living on Mars is protection. Protection from the cold. Protection from the lack of atmosphere. Protection from the radiation from space.
14:16NASA could build shelters, but Martian history offers them a shortcut.
14:23Millions of years ago, the planet's volcanoes erupted huge amounts of lava.
14:34But the silver lining is that as the lava was flowing away, it did that through underground tubes.
14:40And then as the lava evacuated away, it left behind empty caverns, just like this really big lava tube that we're standing in right now.
14:48Martian gravity is a third as strong as Earth's, thanks to the red planet's lower mass.
14:54So when Martian lava flows underground, it meets less resistance and can carve out monstrous cave systems.
15:02Natural astronaut shelters, hidden away from the red planet's dust storms.
15:08If you actually then seal them, you can fill them with air, you've got a great place to live.
15:14These tunnels are ready made for people to move into. We already have the keys.
15:21But a lava tube may not be everyone's idea of home sweet home.
15:26Because they're a natural feature, you can't pick and choose where they are. You have to go to where they already exist.
15:36Building their own shelters gives the astronauts more options where they can live.
15:42And they can be built by robots before the settlers arrive.
15:48We could even send 3D printers. I'm talking about something that actually uses the rock there and makes something like concrete.
15:55And it could build structures for us to live in.
16:00NASA challenged the tech industry to develop Martian shelters built by autonomous robots.
16:07It sounds like something out of a wonderful science fiction story. But we already have this technology.
16:12We on Earth can actually 3D print houses already by actually just adding concrete.
16:16So we have all of the technology necessary to do this. Now it's just, do we have the will?
16:23In May 2019, NASA announced the winning team.
16:28AI Space Factory built a structure that withstood rigorous pressure and impact testing.
16:34It can be 3D printed in 30 hours and made from materials found on Mars.
16:40Once scaled up, the habitat could protect settlers from the inhospitable conditions on the Red Planet.
16:48Even with shelters, the settlers will need to eat, breathe and drink.
16:59But there is no food, breathable oxygen or liquid water on Mars.
17:05So even though Mars is the closest friendly environment to life that there is to the Earth, it's really not all that friendly.
17:12Without easy access to the essentials of life, will settling on Mars be possible?
17:21Compared to Earth, life on Mars is a recipe for disaster.
17:29If you look at it as a human being who wants to live there, yeah, this is an alien world that's going to try to kill you at every step.
17:36It's far away. It's cold. There are just so many reasons why we really wouldn't be happy campers on Mars.
17:43So why on Earth are we talking about sending people there?
17:47Well, the next closest planet, Venus, it's way worse.
17:51Its surface is super hot. It's got horrible chemicals in the atmosphere.
17:56So in comparison, Mars looks like a great, great place to visit.
18:00It's close. It's relatively Earth-like.
18:03And although there are many challenges, there are challenges that we could overcome.
18:08To settle on Mars, NASA's astronauts need a few essentials.
18:13If we want to live there, short-term or long-term, you know, what do you need physically?
18:18Well, you need air. You need water. You need food.
18:22Those are all things that we can bring with us, but it's a lot easier if they exist there on Mars.
18:31The settlers will need to grow their own food, but the Martian ground is poisonous.
18:38Mars' dust looks really benign. It looks kind of like dust you would find in southern Utah.
18:43But it turns out it contains a lot of something called perchlorates.
18:47And these materials are really toxic to human life.
18:51Perchlorates are chemicals formed by electricity produced in Martian dust storms.
18:58And they make up around one percent of the Martian soil.
19:04Which doesn't sound like much, but this could be a significant problem for any humans living on the surface of the Red Planet.
19:12Food grown in the Martian dirt will absorb the perchlorates, posing a health hazard for the astronauts.
19:20But that's not all.
19:22Direct exposure to the toxic soil will make astronauts very sick.
19:29One of the effects that perchlorates have biologically in our bodies is to sort of mess with and alter the function of our thyroid glands.
19:38Astronauts will get rashes, feel nauseous. Extended exposure to the dirt could even kill them.
19:47And Mars is not the sort of place where you would ever want to get seriously ill.
19:51Millions of miles from all the hospitals and health care of the Earth.
19:58There are ideas of how to clean the poisonous soil, using water or bacteria, but the technology is not ready.
20:08The first settlers will need to find a safer way to grow food.
20:12And NASA has the solution.
20:16Hydroponics will provide all the food a Martian settler might need.
20:21Instead of growing in soil, the settlers will grow crops in water.
20:27So all you need to do is bring the seeds or the plants and then have them grow right there in water.
20:33But if we decide to grow our crops hydroponically on Mars, then we still have this problem of needing lots and lots of water.
20:41But before astronauts water their plants, they'll need water to drink.
20:47And Mars hasn't had running water for millions of years.
20:53We've all seen the movies of people stranded in different places and having to survive.
20:57And they can last for months without food.
20:59But a human cannot last beyond three days without water.
21:08Astronauts on the International Space Station recycle water from bathing, breath, urine and sweat.
21:15But they still need 1,500 gallons sent up each year.
21:21Each delivery weighs over six tons.
21:26Transporting water to Mars will add a lot of weight to the manifest.
21:32You have to use fuel to launch it.
21:34But then you also have to use more fuel to launch the weight of the other fuel.
21:38And so on and so on.
21:40You have to keep to an absolute minimum the amount of weight you try to launch from Earth.
21:46So if NASA wants to set up residence on Mars, astronauts will need to find a water source.
21:54Even though no liquid water exists on the planet's surface, there are other places to look.
22:01It turns out there is a lot of water on Mars.
22:04It's trapped underneath the ground, beneath the dirt and the soils at high latitudes.
22:08It's also found in huge volumes up at the polar ice caps.
22:12Ice you melt and it becomes water. You can drink it. Yay!
22:15You can grow plants and do things like that.
22:17In fact, if you were to melt all of Mars' polar ice, then you would be able to cover the globe in water.
22:24So ice is an extremely important thing to have access to.
22:28So if we do go to Mars to explore and live there, following the ice is the way it's going to go.
22:35Even if NASA astronauts can turn the Martian ice into drinking water,
22:41without another resource, settlers will be dead in three minutes.
22:46That resource is oxygen.
22:50There is oxygen on Mars, but it's not in the air. You can't breathe it.
22:53It's bound up in the dirt and combined with iron to make iron oxide, giving it its characteristic,
23:01And so we need to bring it with us, and that's a huge amount to bring,
23:05or we need to make it at Mars, and that's really difficult.
23:09We can deliver oxygen to the ISS.
23:13But the trip to Mars is long, so there will be few supply missions.
23:20Once you're on Mars, you can't pull out your app and order an oxygen delivery ticket.
23:25Once you're on Mars, you can't pull out your app and order an oxygen delivery to your door.
23:30You got to take it with you, and that's a lot of oxygen.
23:34NASA astronauts will need a way to make oxygen on the Red Planet,
23:38and the space agency is working on a solution.
23:46When their 2020 rover arrives on Mars,
23:49it will carry out the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE.
23:58MOXIE will take carbon dioxide from the Martian air,
24:02and use electricity to split that CO2 and release oxygen that astronauts could breathe in the future.
24:11This test will create oxygen on another planet for the first time.
24:16But MOXIE can't make enough for a crewed mission to Mars.
24:21MOXIE will be able to make about half a pound of oxygen per day,
24:26which is only enough to keep a human alive for about six hours.
24:31NASA needs to significantly scale up the technology to support a whole crew on Mars.
24:39But even if the astronauts can survive on the Red Planet,
24:44can they actually reach it?
24:48This is a long trip in a bathtub with three other people.
24:51It's really challenging.
24:53I think we're still asking ourselves this question, how will we do it?
25:01NASA's solution is Orion,
25:04a 28-ton spacecraft nearly twice the mass of a school bus.
25:10The rocket that launches Orion will need to produce millions of pounds of thrust.
25:17And that's a problem.
25:19If we decided tomorrow, like, hey, you know what, let's go to Mars, we can't.
25:24We don't have powerful enough rockets to do it.
25:29In 1969, NASA's Saturn V rocket fired Apollo astronauts to the Moon
25:35with 7.6 million pounds of thrust.
25:38That's the power of more than 34 jumbo jets.
25:42A Saturn V could have sent astronauts to Mars.
25:46Not anymore. We stopped making them.
25:50To break free from Earth's gravity, the space rocket must travel at 25,000 miles an hour.
25:57To achieve that, NASA is building the most powerful rocket in the world.
26:03The Space Launch System, or SLS,
26:05is the rocket that's being designed to carry Orion off of Earth and beyond low Earth orbit.
26:11And the philosophy is, hey, remember those big rockets that we used to make back in the 60s and stuff?
26:17Let's do that again, but more so.
26:22It's really big. It's larger than the Saturn V rocket that was built to carry the Apollo spacecraft
26:27and is therefore going to be the largest rocket built.
26:31The Space Launch System will be taller than the Statue of Liberty.
26:37Its gargantuan engines will thrust the rocket through the atmosphere
26:41with the horsepower of 160,000 Corvettes, producing 8.8 million pounds of thrust.
26:50The SLS will be able to blast the Orion capsule into space and send it on its way to Mars.
27:00Unfortunately, the rocket has fallen behind schedule.
27:04Its maiden test flight was set for December 2017.
27:09Now it's scheduled for the end of 2020.
27:14Critics see the SLS as a waste of money, with the project reported to be billions of dollars over budget.
27:23The key to doing any of this is to have the access to space be affordable.
27:28If it's out of the question to spend the money to do it, we're never going to be able to do it.
27:32And with SpaceX developing reusable rockets, NASA's single-use SLS is beginning to look even less appealing.
27:42The reason air travel is inexpensive is because we figured out how to use planes over and over again, basically.
27:48If we can do that with rockets as well, we don't have to keep building them over and over again.
27:54You can take the rocket, go into space, bring most of that rocket back down and reuse it.
28:00You can save tens or even hundreds of millions of dollars per flight.
28:05They're doing it from the standpoint of making money.
28:08If they bring their rocket back, they can use it again. That makes a lot of sense.
28:11That brings us that much closer to setting foot on the surface of Mars.
28:17It's still hoped NASA's space launch system will go to Mars in the 2030s.
28:25But even though the red planet is our neighbor, the timing of our visit will be complicated.
28:32If you're planning a family vacation and you want to get in the car, it's easy, right?
28:36You look at a map and you say, I live in City A and I want to go to City B and I'll just take the highways there.
28:41Well, great. Now imagine that City A is moving this way at 50 miles per hour and this city is moving this way at 200 miles per hour.
28:49Now what do you do? Well, that is a very small problem compared to getting to another planet.
28:55The timeline of a Mars mission, the scheduling, if you will, is all governed by celestial mechanics, the orbits of the planets.
29:01It's not just you pick a time to go to Mars randomly whenever you feel like going.
29:05You've literally got to wait for the planets to be aligned, right?
29:09On average, the distance from the Earth to Mars is about 140 million miles.
29:14But this is changing all the time because we are both planets that are orbiting the sun.
29:18So about the closest that Earth ever comes to Mars is a distance of about 35 million miles.
29:27But in other times when we're on the opposite side of the sun from Mars, it can be as much as 250 million miles.
29:34Launching near the time of Mars' closest approach shortens the journey.
29:41So NASA can save on fuel and resources, boosting the mission's chances of success.
29:48But this planetary alignment only happens every 26 months.
29:54So if NASA misses a launch window, it will have to wait for over two years for another go.
30:01But simply picking the right time isn't enough.
30:08Mars and the Earth are both orbiting the sun, so Orion can't fly in a straight line to Mars.
30:16Instead, it will use what's known as a Hohmann transfer.
30:21What we want to do is sort of put ourselves on our spacecraft in orbit around the sun.
30:27So we might start right here on Earth, launch our spacecraft,
30:31and essentially we just make a nice gentle arc that's arcing around the sun
30:37so that it can naturally slide into this orbit and then end up on Mars.
30:43The journey will take around 10 months.
30:46To get there quicker means burning more fuel, which isn't an option.
30:52The Hohmann transfer keeps fuel usage low by pulling the craft in an orbit
30:58that gradually intersects with the orbit of Mars before being captured by the red planet's gravity.
31:07But they need to get their direction just right.
31:11The way the orbits work, you've got to aim in a little bit different direction
31:15from where Mars appears to be now.
31:18You've got to aim for where it's going to be when you get there.
31:20This has to happen so that it can naturally slide into this orbit and then end up on Mars.
31:26If we miss that precision, then we just could end up hurtling out into space.
31:32Even if NASA hits their target, the crew has a long 10-month journey in space.
31:40The human body is just simply not designed for long-duration space travel.
31:46Space travel can destroy bones, weaken heart muscles, and even mess with the mind.
31:54Could a crew survive the journey to the red planet?
32:02Out there in a spacecraft between the planets, all bets are off.
32:07It's going to be a dangerous trip.
32:11Both hands down. I've got the fourth rung up.
32:14When astronaut James Irwin stood on the moon, his heart beat irregularly.
32:22Back on Earth, Irwin suffered heart attacks, which eventually proved fatal.
32:28A 2016 study found that the Apollo lunar astronauts are four to five times more likely to die
32:35from cardiovascular disease than astronauts who never left Earth's orbit.
32:42One cause could be space radiation.
32:46And the radiation in outer space won't just be damaging the heart muscles,
32:52but also the nervous system and astronauts' brains in outer space.
32:59Astronauts heading to Mars will face radiation created in the core of stars.
33:05Some comes from our sun, when solar ejections throw out streams of deadly charged particles.
33:18There are also cosmic rays from outside the solar system.
33:23Created in supernovas, the deaths of giant stars,
33:28these energetic particles race through the galaxy at close to the speed of light.
33:34And you don't want to be exposed to too many of them.
33:37In low doses, it's not a problem at all, really.
33:40But in high enough doses, these things penetrate our cells and damage our DNA,
33:44and over the long term, can cause really bad damage to human bodies in space.
33:52The longer you stay in space, the greater the danger.
33:57Remember, our missions to the moon were on the order of a week or two.
34:01A mission to Mars, at the minimum, is going to be something like two or two and a half years, probably.
34:07These cosmic bullets can cause mutations and even cancer.
34:13New research from 2019 suggests space radiation
34:18will cause memory loss in one in three astronauts on a mission to Mars.
34:24And it's not just a problem of forgetting where you've left your keys.
34:28When you're trying to cut back in through the airlock, you do not want to be forgetting emergency procedures.
34:33So we're going to have to really consider how do we mitigate the effects of this radiation
34:38to make it possible for people to go to Mars and actually spend some time without being ill.
34:44So the ship needs to protect the astronauts.
34:48Well, you'd think, well, just, I don't know, build a spaceship out of really thick lead.
34:53Well, that weighs a lot, and it turns out lead doesn't protect you from this kind of radiation.
34:57You need something else.
34:59Well, there is something else that protects you from this radiation, and that's water.
35:03We need to bring lots and lots of water to drink and cook with.
35:07And if we just place that water in a layer around our spacecraft, that can absorb the cosmic rays.
35:13You might think, well, you're drinking the very water that you're using to stop the radiation that's causing damage to us.
35:19Won't the water be dangerous to drink? It doesn't really work quite like that.
35:23You're just taking one high-speed subatomic particle and changing it into another one as it gets captured by the water.
35:30Water is still going to be safe to drink, fortunately.
35:33But even if NASA can shield its astronauts from radiation, space causes other health issues.
35:43Your bones are starting to demineralize. They're getting weak.
35:47You're getting arthritis even in the prime of your life.
35:51Weightlessness during the 10-month journey will thin the astronauts' bones.
35:56Muscles will waste away, making walking on landing difficult.
36:02We've evolved, we've grown up on a planet with gravity.
36:07And as soon as you're an astronaut in outer space, floating around in weightlessness,
36:12it looks like a lot of fun, but actually your body is deteriorating from the inside.
36:19Astronauts need assistance to walk when returning to Earth.
36:23If NASA's Mars crew arrives on the Red Planet in a poor physical state, they won't be able to function.
36:36Intense exercise regimes in space would help the crew stay fit and healthy.
36:42But we are in the dark about the full impact of extended space travel.
36:51On a mission to Mars, bodies would be pushed to the extreme.
36:56It's not just the physical challenges.
37:00Isolation is going to be a major problem for the Mars astronauts.
37:05They will be away from home for at least two and a half years.
37:11So NASA is learning lessons from isolated humans on Earth.
37:18Field studies in Antarctica are really good highlights of what it might be like to endure all of the challenges of spaceflight.
37:25Because no one can get to you quickly. You're in literally the middle of nowhere on a big ice sheet.
37:30And you're just sitting there in tents, two people per tent, and about eight people, and you're there for six weeks.
37:36It's a really alien world. The sun never sets in the summer.
37:41There's nothing alive anywhere around you. Not an insect, not a bird, nothing.
37:46All you can hear is the wind. And the only people that you can speak to are your teammates.
37:52And it's for this reason that NASA uses some of these projects as training missions for their astronaut corps.
37:57The worst part about being in Antarctica, which I think would be the same in long-duration spaceflight,
38:03is that you really reach your limit. I think it really kind of highlights the best and worst of yourself.
38:09Even the most introverted introvert on Earth still needs other people to live.
38:15And this is something that I think we don't really fully appreciate when we're on Earth.
38:19What we found is that it helps to be really open and just communicate your problems.
38:24And so, gosh, I'm not feeling very well lately. I'm feeling a little bit of stress.
38:29I don't really know what to do. And you talk to each other and you work through those things.
38:34Antarctica offers clues to how humans cope thousands of miles from civilization
38:40and helps NASA to plan medicines, communication strategies, and psychological tests
38:46to stop mental health problems jeopardizing a journey to Mars.
38:53But Earth-bound simulations only provide a limited amount of data.
38:58And the teams know that in an emergency, they can be evacuated to safety.
39:04On Mars, rescue could take years, if it comes at all.
39:11To say that sending humans to Mars is a challenge would be an understatement.
39:16We could be ahead of ourselves.
39:19Eventually, we're going to lose people doing this, and that's something we have to face.
39:23The question is, is it worth it?
39:26But there may not be a choice.
39:34Despite the challenges, the mission needs to be a success.
39:40Earth is in danger from climate change, asteroid strikes, and nuclear destruction.
39:51We need an escape plan.
39:54Earth may just need a lifeboat in the future.
39:57We are growing very quickly, and we're using a lot of our resources, and we're changing the planet.
40:05If we're looking for a lifeboat, maybe Mars is the closest, best chance we've got.
40:12NASA's goal is to send the Orion spacecraft to Mars in the 2030s.
40:22But to do that, we need a rehearsal.
40:25I'd love to see us go to Mars. I would love to go myself.
40:28But it might be nice to have a little bit of practice before we try it.
40:35Where better to practice than a destination closer to home?
40:40The ultimate aim is to get humans to Mars,
40:43and one approach is to first have a goal of getting humans back to the moon.
40:49Orion will first make the shorter trip to the moon.
40:55There are a lot of advantages to using the moon.
40:58We can test out different scenarios for operations.
41:01We can also test out technologies much more close to home.
41:05And so if something were to go awry, we can much more easily intervene.
41:09It's a little bit safer.
41:11If we send people to Mars, it's going to be a lot harder for us to help them if they need it.
41:20NASA's Orion moon missions will be far more than just a training exercise.
41:28It will use them to build a lunar outpost called Gateway,
41:32a space station in orbit around the moon.
41:36It's actually a lot easier to do that than trying to build something on Earth and get it out of Earth orbit.
41:42Six planned missions will build and maintain a space station in orbit around the moon.
41:50It will be a proving ground for the technology and science that will help us get to the red planet.
41:57And once NASA has ironed out any problems, the real mission can begin.
42:03Gateway won't simply be a small step for man, but a springboard to another planet.
42:11When we first sent humans to another planetary body, it was the moon.
42:15And we had never done that before.
42:17So now we've got the moon under our belt.
42:20We know something about how to send people to another planet.
42:23We don't yet have all the technologies that we might need to send humans to Mars, but we're well on our way.
42:31As NASA begins its journey to the red planet, not everyone is on board.
42:39A lot of people think of Mars as our lifeboat, just in case we screw things up on Earth.
42:43But we really need to take care of our own planet.
42:46If you want to go there and explore or build a base, more power to you.
42:52But I'm going to stay where it's a little bit more green and blue.
43:01Even so, NASA is already building rockets and testing the technology.
43:07The stage is set for humankind's greatest adventure.
43:13I think we will send humans to Mars.
43:16It's just a really, really, really big problem that we have to figure out how to solve.
43:21But we're good at solving problems.
43:24Given the human mind and how curious we are and how much we like to climb the next mountain and achieve the next challenge, Mars is right there.
43:33There is something in the human psyche that will send us to Mars despite all of the challenges.
43:37And so for sure, we will go to Mars.
43:41Even though it's extremely difficult to go to Mars, the answer is always yes if somebody asks me if we should go.
43:47Because that's the ultimate goal.
43:51NASA Jet Propulsion Laboratory, California Institute of Technology