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NASA has set its sights on Mars.
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Its goal is to send humans
to the red planet
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00:00:12,130 --> 00:00:14,946
in the next 20 years.
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00:00:14,970 --> 00:00:16,346
Looking up at Mars in the sky,
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00:00:16,370 --> 00:00:18,046
I really do feel like
I'm looking at a place
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that someday there will
be people walking around on it.
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It feels so much like earth
in so many ways,
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and it's a place that really
captures my imagination
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as a result.
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It's the most
earthlike environment
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we see in our solar system.
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00:00:34,080 --> 00:00:36,026
So we're not going
to leave it alone.
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00:00:36,050 --> 00:00:38,766
We're going to try to do this.
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00:00:38,790 --> 00:00:41,466
But conquering
our planetary neighbor
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00:00:41,490 --> 00:00:45,336
is a tougher challenge
than we ever thought possible.
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It's an isolated environment
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00:00:47,430 --> 00:00:49,446
where a million things
can go wrong,
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00:00:49,470 --> 00:00:52,500
where there's absolutely
no hope of rescue.
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00:00:54,500 --> 00:00:56,116
There are so many hurdles
to overcome
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00:00:56,140 --> 00:00:59,486
for human exploration of Mars,
and it makes it quite difficult.
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00:00:59,510 --> 00:01:03,086
Sure, we can get there, but are
we going to be in one piece?
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00:01:03,110 --> 00:01:07,626
Sometimes it feels like Mars
is designed to keep us away.
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00:01:07,650 --> 00:01:10,250
Are we doomed to fail
in this endeavor?
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Captions by vitac...
www.vitac.com
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captions paid for by
discovery communications
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♪
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The red planet...
earth's neighbor
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00:01:30,340 --> 00:01:36,026
and the destination of NASA's
most ambitious mission to date.
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But this expedition
will be harder
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00:01:38,720 --> 00:01:41,226
than we ever thought possible.
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00:01:41,250 --> 00:01:44,066
It hurts to think
of how hard it is.
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It's the farthest a human being
has ever been from the earth.
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We got to take every precaution
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00:01:50,230 --> 00:01:53,036
as NASA's astronauts
arrive at Mars,
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00:01:53,060 --> 00:01:55,946
they'll face a huge obstacle.
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00:01:55,970 --> 00:01:59,500
Landing on the planet
is a daunting task.
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00:02:02,540 --> 00:02:07,686
In the past, Mars hasn't always
rolled out the welcome mat.
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00:02:07,710 --> 00:02:10,456
Mars is kind of like
a graveyard for spacecraft.
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00:02:10,480 --> 00:02:13,356
It's actually really hard
to send something from earth
40
00:02:13,380 --> 00:02:15,796
and land it on Mars.
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00:02:15,820 --> 00:02:18,096
This is how
the European space agency
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00:02:18,120 --> 00:02:22,166
hoped its $250 million
Schiaparelli lander
43
00:02:22,190 --> 00:02:24,890
would touch down in 2016...
44
00:02:26,900 --> 00:02:30,370
...but the lander's systems
got it wrong.
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The parachute detached early,
sending the craft into free fall
46
00:02:36,370 --> 00:02:38,110
for 33 seconds.
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00:02:40,340 --> 00:02:42,526
Schiaparelli smashed
into the surface
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00:02:42,550 --> 00:02:46,196
at 335 miles an hour,
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leaving a deep, black scar
on the martian landscape.
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00:02:51,390 --> 00:02:52,696
It turns out that Mars
is actually
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00:02:52,720 --> 00:02:55,506
a particularly difficult planet
to land on.
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00:02:55,530 --> 00:02:57,506
Even humanity's most
brilliant engineers,
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00:02:57,530 --> 00:02:59,636
we've got about
a 50% success rate
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00:02:59,660 --> 00:03:02,506
when it comes
to landing on Mars.
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00:03:02,530 --> 00:03:05,846
The red planet is littered
with dead spacecraft
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00:03:05,870 --> 00:03:08,000
that didn't stick the landing.
57
00:03:10,140 --> 00:03:13,356
And for NASA's first
crewed descent to Mars,
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00:03:13,380 --> 00:03:17,956
the space agency must learn
from these mistakes.
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00:03:17,980 --> 00:03:20,896
But as the crew hurdles
toward the surface
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00:03:20,920 --> 00:03:22,666
they're battling
the same problem
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00:03:22,690 --> 00:03:25,450
as all the landers
that failed before.
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00:03:29,290 --> 00:03:30,666
The martian atmosphere
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00:03:30,690 --> 00:03:33,136
is 100 times thinner
than earth's
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00:03:33,160 --> 00:03:34,906
so it can't provide
the drag needed
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00:03:34,930 --> 00:03:38,716
to slow a spacecraft down.
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00:03:38,740 --> 00:03:40,246
So it's not like the earth,
where you can have
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00:03:40,270 --> 00:03:41,786
these big, giant parachutes
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00:03:41,810 --> 00:03:44,870
that gently glide you down
to the surface.
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00:03:47,740 --> 00:03:51,410
You can use some of the air,
but it's hard.
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00:03:53,580 --> 00:03:55,796
The red planet's thin atmosphere
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00:03:55,820 --> 00:04:00,096
is a problem that's been
billions of years in the making.
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00:04:00,120 --> 00:04:01,396
Mars doesn't have
a large atmosphere
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00:04:01,420 --> 00:04:04,636
because it's constantly
being peeled away
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00:04:04,660 --> 00:04:07,900
due to the lack of protection
of a magnetic field.
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00:04:10,370 --> 00:04:14,876
The solar wind
can strip away an atmosphere.
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00:04:14,900 --> 00:04:18,816
On earth, a liquid metal core
creates a magnetic field
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00:04:18,840 --> 00:04:22,680
which shields the planet and
helps maintain the atmosphere.
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00:04:25,380 --> 00:04:29,126
Mars is different.
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00:04:29,150 --> 00:04:31,496
4.5 billion years ago,
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Mars and earth formed from dust
and gas in space.
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Mars forms where
building materials were scarce.
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00:04:42,800 --> 00:04:46,616
Its growth was stunted.
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00:04:46,640 --> 00:04:48,986
So Mars is much smaller
than the earth.
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It's a factor of 10 smaller
than the earth,
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00:04:51,040 --> 00:04:54,586
and that factor of 10 in mass
is important.
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00:04:54,610 --> 00:04:58,526
All of that extra mass
allows the inside of the earth
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00:04:58,550 --> 00:05:01,496
to stay warm and to have a core
that's rotating,
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00:05:01,520 --> 00:05:03,020
which generates
a magnetic field.
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00:05:04,790 --> 00:05:08,506
4 billion years ago,
the churning heart of Mars
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00:05:08,530 --> 00:05:11,190
started to cool and solidify.
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00:05:13,300 --> 00:05:18,416
With no hot core, there's no
magnetic field being generated.
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00:05:18,440 --> 00:05:22,016
All of the high-velocity charged
particles coming from the sun
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00:05:22,040 --> 00:05:25,870
pick away at the atmosphere
and slowly tear it away.
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00:05:27,910 --> 00:05:30,526
We know it's losing atmosphere
every second
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00:05:30,550 --> 00:05:31,856
due to the solar wind.
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00:05:31,880 --> 00:05:34,680
So, you know,
bye-bye atmosphere.
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♪
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00:05:43,890 --> 00:05:46,436
With little martian
atmosphere to work with,
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00:05:46,460 --> 00:05:50,306
NASA had to be creative
to get its crewless landers
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00:05:50,330 --> 00:05:52,046
to the martian surface.
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00:05:52,070 --> 00:05:57,316
♪
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In 2012,
the revolutionary sky crane
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00:06:00,610 --> 00:06:05,680
landed the curiosity rover using
parachutes and retro rockets.
104
00:06:08,550 --> 00:06:11,196
Previous missions have used
both a parachute
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00:06:11,220 --> 00:06:13,566
and something else
like a bouncy ball
106
00:06:13,590 --> 00:06:15,836
inflated around the spacecraft.
107
00:06:15,860 --> 00:06:21,506
♪
108
00:06:21,530 --> 00:06:24,146
I don't think a human crew
is going to be too pleased
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00:06:24,170 --> 00:06:25,746
if they're gonna be bouncing
onto the surface
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00:06:25,770 --> 00:06:29,016
in an airbag,
rolling to a stop, right?
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00:06:29,040 --> 00:06:34,816
To land people on Mars,
NASA will need some new tricks.
112
00:06:34,840 --> 00:06:39,096
The 2020 rover will overcome
the challenge with the advanced
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00:06:39,120 --> 00:06:43,366
supersonic parachute inflation
research experiment,
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00:06:43,390 --> 00:06:46,436
a.s.p.i.r.e.
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00:06:46,460 --> 00:06:50,736
It will rapidly
slow down the craft
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00:06:50,760 --> 00:06:53,930
with the force
of an airplane jet engine.
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This is fine for the rover.
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00:06:58,100 --> 00:06:59,746
It's actually gonna work
no problem.
119
00:06:59,770 --> 00:07:02,846
But it's not going to work
for people.
120
00:07:02,870 --> 00:07:05,216
A human lander
will weigh far more
121
00:07:05,240 --> 00:07:08,386
than the 2,300-pound rover.
122
00:07:08,410 --> 00:07:10,286
Not even supersonic parachutes
123
00:07:10,310 --> 00:07:12,780
could land a crew
safely on Mars.
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00:07:15,120 --> 00:07:18,226
NASA will need a new plan.
125
00:07:18,250 --> 00:07:22,266
One idea is to use
the thin martian atmosphere
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00:07:22,290 --> 00:07:24,206
in a unique way.
127
00:07:24,230 --> 00:07:26,536
There's an idea of coming
in really fast,
128
00:07:26,560 --> 00:07:28,476
getting to the thick part
of the atmosphere,
129
00:07:28,500 --> 00:07:30,646
and then going horizontal
to the ground
130
00:07:30,670 --> 00:07:33,730
and gliding and losing
your momentum that way.
131
00:07:37,870 --> 00:07:39,586
As the astronauts descend,
132
00:07:39,610 --> 00:07:43,726
they tilt the nose of the lander
towards the martian surface
133
00:07:43,750 --> 00:07:46,356
aiming for the thickest part
of the atmosphere
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00:07:46,380 --> 00:07:48,666
close to the ground.
135
00:07:48,690 --> 00:07:51,396
Then they pull up
at the last second
136
00:07:51,420 --> 00:07:55,020
using friction from the
atmosphere to slow the craft.
137
00:07:57,090 --> 00:08:01,076
Descent engines switch on
for the final touchdown.
138
00:08:01,100 --> 00:08:08,346
♪
139
00:08:08,370 --> 00:08:09,816
Is this a crazy idea?
140
00:08:09,840 --> 00:08:12,516
I mean, yeah,
it's a little bit weird.
141
00:08:12,540 --> 00:08:13,886
I don't know if we'd really
think about it,
142
00:08:13,910 --> 00:08:15,256
doing something like this,
143
00:08:15,280 --> 00:08:18,526
but, I mean, you've got to think
outside the box sometimes.
144
00:08:18,550 --> 00:08:22,166
Right now, NASA's plans
for landing a craft on Mars
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00:08:22,190 --> 00:08:24,266
are still on the drawing board.
146
00:08:24,290 --> 00:08:27,866
But even if they can
get astronauts onto the surface,
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00:08:27,890 --> 00:08:32,706
the thin atmosphere
isn't done with them yet.
148
00:08:32,730 --> 00:08:35,406
It causes swirling dust storms
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00:08:35,430 --> 00:08:38,046
that cover
the planet's entire surface.
150
00:08:38,070 --> 00:08:39,646
Mars doesn't just have
dust devils.
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00:08:39,670 --> 00:08:42,346
It has dust hell.
152
00:08:42,370 --> 00:08:47,340
And these towering clouds
have killed before.
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00:08:58,050 --> 00:09:03,236
♪
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00:09:03,260 --> 00:09:07,936
If NASA's astronauts arrive
on Mars as planned, in 2035,
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00:09:07,960 --> 00:09:10,646
the settlers will find
one of the red planet's
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00:09:10,670 --> 00:09:13,730
biggest challenges is its dust.
157
00:09:17,140 --> 00:09:18,656
It's sticky,
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00:09:18,680 --> 00:09:20,716
basically, light from the sun
159
00:09:20,740 --> 00:09:22,656
can give the stuff
a static charge
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00:09:22,680 --> 00:09:24,656
and then it clings to stuff.
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00:09:24,680 --> 00:09:26,256
So it's not just a matter
of, like, you know,
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00:09:26,280 --> 00:09:29,026
standing on a doormat
outside your your space habitat
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00:09:29,050 --> 00:09:30,466
and shaking yourself off.
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00:09:30,490 --> 00:09:31,626
It's gonna get
in your space suit.
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00:09:31,650 --> 00:09:33,296
It's gonna coat your visor.
166
00:09:33,320 --> 00:09:34,800
It's going to cover
your solar panels.
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00:09:36,230 --> 00:09:38,636
If you get it in your lungs,
it's not a good thing.
168
00:09:38,660 --> 00:09:41,400
We have to figure out how to
clear this stuff out.
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00:09:43,170 --> 00:09:46,546
300 feet.
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00:09:46,570 --> 00:09:50,046
Through the '60s and '70s,
171
00:09:50,070 --> 00:09:53,716
Apollo astronauts
walked on the moon.
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00:09:53,740 --> 00:09:55,856
When they returned
to their landing module,
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00:09:55,880 --> 00:09:58,350
they brought moon dust back
with them.
174
00:10:00,720 --> 00:10:04,426
The lunar dust clogged seals,
caused equipment to overheat,
175
00:10:04,450 --> 00:10:07,496
and resulted
in false instrument readings.
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00:10:07,520 --> 00:10:10,706
It even made
the astronauts sick.
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00:10:10,730 --> 00:10:13,906
You don't want to be breathing
in fine, dusty material
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00:10:13,930 --> 00:10:16,606
by itself, you can get things
like silicosis.
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00:10:16,630 --> 00:10:19,276
It's, you know,
almost basically a lung cancer
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00:10:19,300 --> 00:10:21,146
that you can get just
from breathing the dust itself.
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00:10:21,170 --> 00:10:23,846
You don't want to do that.
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00:10:23,870 --> 00:10:27,586
The red planet is covered
in sticky dust,
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00:10:27,610 --> 00:10:32,150
and new research suggests
it all came from one place...
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00:10:35,750 --> 00:10:38,796
...the Medusae Fossae formation.
185
00:10:38,820 --> 00:10:41,696
When the 600-mile-long
volcanic deposit formed
186
00:10:41,720 --> 00:10:43,406
3 billion years ago,
187
00:10:43,430 --> 00:10:47,506
it was around half the size
of the United States,
188
00:10:47,530 --> 00:10:50,376
but the martian winds
have eroded this structure
189
00:10:50,400 --> 00:10:53,530
and spread the dust
across the entire planet.
190
00:10:56,570 --> 00:10:58,816
When the wind whips
up this dust,
191
00:10:58,840 --> 00:11:02,626
it can have
disastrous consequences.
192
00:11:02,650 --> 00:11:06,056
The real problem is just that
all these fine particles
193
00:11:06,080 --> 00:11:08,196
get lofted into the atmosphere,
194
00:11:08,220 --> 00:11:11,166
and it takes a really long time
for them to settle back out.
195
00:11:11,190 --> 00:11:13,866
And what the dust does
is it just gets up in the sky
196
00:11:13,890 --> 00:11:17,206
and it sits there
and sits there and sits there.
197
00:11:17,230 --> 00:11:20,636
As more material gets lifted
into the atmosphere,
198
00:11:20,660 --> 00:11:24,546
it forms huge dust storms.
199
00:11:24,570 --> 00:11:27,846
The storms are so large
they block out the sunlight
200
00:11:27,870 --> 00:11:29,970
and cool the martian surface...
201
00:11:32,240 --> 00:11:34,016
...creating
a temperature difference
202
00:11:34,040 --> 00:11:36,626
between the ground
and atmosphere
203
00:11:36,650 --> 00:11:40,510
that causes winds to increase
and the storms to grow.
204
00:11:43,490 --> 00:11:46,896
And NASA's opportunity
rover knows firsthand
205
00:11:46,920 --> 00:11:50,666
the dangers of being
trapped in one.
206
00:11:50,690 --> 00:11:54,936
Opportunity was a NASA rover
sent to Mars
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00:11:54,960 --> 00:11:59,946
to hunt for signs of past water
on the surface
208
00:11:59,970 --> 00:12:03,546
and potentially signs
of past life.
209
00:12:03,570 --> 00:12:06,456
This is a rover that we really
worked with so long,
210
00:12:06,480 --> 00:12:08,926
knew so well,
and who had come up with
211
00:12:08,950 --> 00:12:13,326
so many amazing new results
from Mars.
212
00:12:13,350 --> 00:12:15,526
June 2018.
213
00:12:15,550 --> 00:12:18,590
Opportunity was
15 years into its mission...
214
00:12:20,360 --> 00:12:24,736
...when giant clouds of dust
appeared on the horizon.
215
00:12:24,760 --> 00:12:30,846
NASA could only watch
as the storm grew and grew.
216
00:12:30,870 --> 00:12:34,716
Once this dust storm coated
the entire planet,
217
00:12:34,740 --> 00:12:36,516
it blocked the sun.
218
00:12:36,540 --> 00:12:40,056
And the sun was the source
of opportunity's power.
219
00:12:40,080 --> 00:12:42,526
Opportunity works
using solar panels,
220
00:12:42,550 --> 00:12:46,626
and so it gradually got less
and less and less electricity.
221
00:12:46,650 --> 00:12:49,520
For opportunity,
there was no escape.
222
00:12:51,790 --> 00:12:53,596
Lost in the darkness,
223
00:12:53,620 --> 00:12:58,206
opportunity's power reserves
slowly ran dry.
224
00:12:58,230 --> 00:13:02,206
The rover fell silent.
225
00:13:02,230 --> 00:13:04,746
We thought, well, maybe
once the dust storm clears up
226
00:13:04,770 --> 00:13:07,476
the panels can fire up again
and we can get it back,
227
00:13:07,500 --> 00:13:11,186
but it just never woke up.
228
00:13:11,210 --> 00:13:14,416
If NASA's astronauts
do make it to Mars,
229
00:13:14,440 --> 00:13:18,310
the storms could damage more
than the crew's power supply.
230
00:13:21,620 --> 00:13:26,836
When the storms begin to blow,
they crackle with electricity.
231
00:13:26,860 --> 00:13:28,766
Just like you can create
a static charge
232
00:13:28,790 --> 00:13:30,166
by rubbing your foot
on the carpet
233
00:13:30,190 --> 00:13:32,106
or a balloon on your hair,
234
00:13:32,130 --> 00:13:36,506
this happens at large scale
in these dust storms on Mars.
235
00:13:36,530 --> 00:13:38,506
The sand grains rub up
against each other,
236
00:13:38,530 --> 00:13:40,776
and that creates
a static charge.
237
00:13:40,800 --> 00:13:44,846
So you get these electrical
flows that occur.
238
00:13:44,870 --> 00:13:47,286
Here on earth, we see this
in volcanic eruptions
239
00:13:47,310 --> 00:13:49,886
as the dust,
the ash burbling out
240
00:13:49,910 --> 00:13:51,226
of one of these huge eruptions.
241
00:13:51,250 --> 00:13:54,226
You'll see lightning discharges
in those volcanic plumes
242
00:13:54,250 --> 00:13:57,096
from this same charge transfer.
243
00:13:57,120 --> 00:13:59,466
If you're in a place with a
lot of electrostatic discharge,
244
00:13:59,490 --> 00:14:01,336
that means sparks
are going to fly,
245
00:14:01,360 --> 00:14:05,776
which is really terrible
for operating instruments.
246
00:14:05,800 --> 00:14:07,476
To survive on Mars,
247
00:14:07,500 --> 00:14:12,476
the settlers are going to need
a protective shelter.
248
00:14:12,500 --> 00:14:15,816
The keyword to living
on Mars is protection...
249
00:14:15,840 --> 00:14:17,746
protection from the cold,
250
00:14:17,770 --> 00:14:19,556
protection from the lack
of atmosphere,
251
00:14:19,580 --> 00:14:22,310
protection from the radiation
from space.
252
00:14:25,310 --> 00:14:27,426
NASA could build shelters,
253
00:14:27,450 --> 00:14:32,366
but martian history
offers them a shortcut.
254
00:14:32,390 --> 00:14:34,366
Millions of years ago,
255
00:14:34,390 --> 00:14:38,430
the planet's volcanoes
erupted huge amounts of lava.
256
00:14:42,730 --> 00:14:44,146
But the silver lining is that,
257
00:14:44,170 --> 00:14:46,346
as the lava was flowing away,
258
00:14:46,370 --> 00:14:49,016
it did that
through underground tubes.
259
00:14:49,040 --> 00:14:50,616
And then as the lava
evacuated away,
260
00:14:50,640 --> 00:14:52,556
it left behind empty caverns,
261
00:14:52,580 --> 00:14:54,286
just like this really
big lava tube
262
00:14:54,310 --> 00:14:57,286
that we're standing in
right now.
263
00:14:57,310 --> 00:15:00,656
Martian gravity is a third
as strong as earth's
264
00:15:00,680 --> 00:15:04,126
thanks to the red planet's
lower mass.
265
00:15:04,150 --> 00:15:06,666
So when martian lava flows
underground,
266
00:15:06,690 --> 00:15:08,236
it meets less resistance
267
00:15:08,260 --> 00:15:11,606
and can carve out
monstrous cave systems,
268
00:15:11,630 --> 00:15:14,006
natural astronaut shelters
269
00:15:14,030 --> 00:15:17,106
hidden away
from the dust storms.
270
00:15:17,130 --> 00:15:20,446
If you actually then seal them,
you can fill them with air.
271
00:15:20,470 --> 00:15:23,046
You've got
a great place to live.
272
00:15:23,070 --> 00:15:26,856
These tunnels are ready-made
for people to move into.
273
00:15:26,880 --> 00:15:29,986
We already have the keys.
274
00:15:30,010 --> 00:15:33,356
But a lava tube may not be
everyone's idea
275
00:15:33,380 --> 00:15:35,666
of home sweet home.
276
00:15:35,690 --> 00:15:38,166
Because they're
a natural feature,
277
00:15:38,190 --> 00:15:39,896
you can't pick and choose
where they are.
278
00:15:39,920 --> 00:15:42,590
You have to go
to where they already exist.
279
00:15:45,560 --> 00:15:47,206
Building their own shelters
280
00:15:47,230 --> 00:15:50,746
gives the astronauts
more choices,
281
00:15:50,770 --> 00:15:53,476
and they can be built by robots
282
00:15:53,500 --> 00:15:57,116
before the settlers even arrive.
283
00:15:57,140 --> 00:15:59,886
And we could even send
3-d printers.
284
00:15:59,910 --> 00:16:02,726
I'm talking about something that
actually uses the rock there
285
00:16:02,750 --> 00:16:04,686
and makes something
like concrete,
286
00:16:04,710 --> 00:16:07,996
and it could build structures
for us to live in.
287
00:16:08,020 --> 00:16:10,666
Even with shelters,
the settlers will still need
288
00:16:10,690 --> 00:16:13,996
to eat, breathe, and drink.
289
00:16:14,020 --> 00:16:17,466
But there is no food,
no breathable oxygen,
290
00:16:17,490 --> 00:16:20,236
and no liquid water on Mars.
291
00:16:20,260 --> 00:16:23,206
So even though Mars is the
closest friendly environment
292
00:16:23,230 --> 00:16:24,876
to life that there is
to the earth,
293
00:16:24,900 --> 00:16:26,976
it's really not
all that friendly.
294
00:16:27,000 --> 00:16:30,316
Without easy access
to the essentials of life,
295
00:16:30,340 --> 00:16:33,640
will settling on Mars
be possible?
296
00:16:44,650 --> 00:16:48,496
♪
297
00:16:48,520 --> 00:16:51,330
Humans have evolved
to life on earth.
298
00:16:53,960 --> 00:16:58,946
We have oxygen to breathe, water
to drink, and food to eat...
299
00:16:58,970 --> 00:17:01,270
everything we need to survive.
300
00:17:04,670 --> 00:17:06,156
Compared to earth,
301
00:17:06,180 --> 00:17:10,186
life on Mars
is a recipe for disaster.
302
00:17:10,210 --> 00:17:13,196
If you look at it as a human
being who wants to live there,
303
00:17:13,220 --> 00:17:14,796
yeah, this is an alien world
304
00:17:14,820 --> 00:17:17,426
that's going to try to kill you
at every step.
305
00:17:17,450 --> 00:17:19,366
It's far away. It's cold.
306
00:17:19,390 --> 00:17:20,996
There are just
so many reasons why
307
00:17:21,020 --> 00:17:23,966
we really wouldn't be
happy campers on Mars.
308
00:17:23,990 --> 00:17:25,206
So why on earth are we talking
309
00:17:25,230 --> 00:17:27,576
about sending people there?
310
00:17:27,600 --> 00:17:31,046
Well, the next closest planet,
Venus, it's way worse.
311
00:17:31,070 --> 00:17:33,446
Its surface is super hot.
312
00:17:33,470 --> 00:17:36,286
It's got horrible chemicals
in the atmosphere.
313
00:17:36,310 --> 00:17:37,486
So in comparison,
314
00:17:37,510 --> 00:17:39,716
Mars looks like
a great, great place to visit.
315
00:17:39,740 --> 00:17:42,786
It's close,
it's relatively earthlike,
316
00:17:42,810 --> 00:17:44,826
and although
there are many challenges
317
00:17:44,850 --> 00:17:48,196
they're challenges
that we could overcome.
318
00:17:48,220 --> 00:17:49,496
To settle on Mars,
319
00:17:49,520 --> 00:17:53,396
NASA's astronauts
need a few essentials.
320
00:17:53,420 --> 00:17:56,466
If we want to live there,
short term or long term,
321
00:17:56,490 --> 00:17:58,036
you know,
what do you need physically?
322
00:17:58,060 --> 00:18:02,806
Well, you need air.
You need water. You need food.
323
00:18:02,830 --> 00:18:05,676
Those are all things
that we can bring with us,
324
00:18:05,700 --> 00:18:11,616
but it's a lot easier
if they exist there on Mars.
325
00:18:11,640 --> 00:18:14,416
The settlers will need
to grow their own food,
326
00:18:14,440 --> 00:18:19,156
but the martian ground
is poisonous.
327
00:18:19,180 --> 00:18:20,856
Mars' dust looks really benign.
328
00:18:20,880 --> 00:18:23,466
It looks kind of like dust
you would find in Southern Utah.
329
00:18:23,490 --> 00:18:24,966
But it turns out it contains
330
00:18:24,990 --> 00:18:27,266
a lot of something
called perchlorate,
331
00:18:27,290 --> 00:18:30,320
and these materials
are really toxic to human life.
332
00:18:32,560 --> 00:18:36,076
Perchlorates are chemicals
formed by electricity
333
00:18:36,100 --> 00:18:39,006
produced in martian dust storms.
334
00:18:39,030 --> 00:18:43,916
And they make up about
1% of the martian soil
335
00:18:43,940 --> 00:18:45,586
which doesn't sound like much,
336
00:18:45,610 --> 00:18:48,086
but this could be
a significant problem
337
00:18:48,110 --> 00:18:51,926
for any humans living on
the surface of the red planet.
338
00:18:51,950 --> 00:18:56,226
Food grown in the martian dirt
will absorb the perchlorates,
339
00:18:56,250 --> 00:19:00,466
posing a health hazard
for the astronauts.
340
00:19:00,490 --> 00:19:02,766
But that's not all.
341
00:19:02,790 --> 00:19:05,506
Direct exposure
to the toxic soil
342
00:19:05,530 --> 00:19:08,000
will make astronauts very sick.
343
00:19:10,430 --> 00:19:11,846
One of the effects
that perchlorates
344
00:19:11,870 --> 00:19:15,886
have biologically in our bodies
is to sort of mess with
345
00:19:15,910 --> 00:19:19,486
and alter the function
of our thyroid glands.
346
00:19:19,510 --> 00:19:23,086
Astronauts would get rashes
and feel nauseous.
347
00:19:23,110 --> 00:19:27,926
Extended exposure to the dirt
could even kill them.
348
00:19:27,950 --> 00:19:29,296
And Mars is not
the sort of place
349
00:19:29,320 --> 00:19:32,096
where you would ever want
to get seriously ill,
350
00:19:32,120 --> 00:19:34,296
millions of miles from all
the hospitals
351
00:19:34,320 --> 00:19:36,790
and health care of the earth.
352
00:19:38,730 --> 00:19:42,606
There are ideas of how
to clean the poisonous soil
353
00:19:42,630 --> 00:19:44,746
using water or bacteria,
354
00:19:44,770 --> 00:19:48,176
but the technology
is not yet ready.
355
00:19:48,200 --> 00:19:52,616
The first settlers will need to
find a safer way to grow food,
356
00:19:52,640 --> 00:19:57,386
and NASA has the solution...
hydroponics.
357
00:19:57,410 --> 00:19:59,556
Hydroponics will provide
all the food
358
00:19:59,580 --> 00:20:02,296
a martian settler might need.
359
00:20:02,320 --> 00:20:07,466
Instead of growing in soil,
the settlers grow crops in water
360
00:20:07,490 --> 00:20:10,706
so all you need to do
is bring the seeds or the plants
361
00:20:10,730 --> 00:20:13,706
and then have them grow
right there in water.
362
00:20:13,730 --> 00:20:17,246
But if we decide to grow our
crops hydroponically on Mars,
363
00:20:17,270 --> 00:20:18,476
then we still have this problem
364
00:20:18,500 --> 00:20:22,216
of needing lots
and lots of water.
365
00:20:22,240 --> 00:20:24,646
Before astronauts
water their plants,
366
00:20:24,670 --> 00:20:27,556
they'll need water to drink,
367
00:20:27,580 --> 00:20:33,556
and Mars hasn't had running
water for millions of years.
368
00:20:33,580 --> 00:20:34,956
We've all seen the movies
of people
369
00:20:34,980 --> 00:20:37,226
stranded in different places
and having to survive
370
00:20:37,250 --> 00:20:39,396
and they can last
for months without food.
371
00:20:39,420 --> 00:20:42,960
But a human cannot last
beyond three days without water.
372
00:20:47,560 --> 00:20:50,276
Astronauts on
the international space station
373
00:20:50,300 --> 00:20:57,416
recycle water from bathing,
breath, urine, and sweat,
374
00:20:57,440 --> 00:21:01,916
but they still need
1,500 gallons sent up each year.
375
00:21:01,940 --> 00:21:04,780
Each delivery weighs
over six tons.
376
00:21:07,150 --> 00:21:09,226
Transporting water to Mars
377
00:21:09,250 --> 00:21:12,296
will add a lot of weight
to the manifest.
378
00:21:12,320 --> 00:21:14,666
You have to use fuel
to launch it
379
00:21:14,690 --> 00:21:16,536
but then you also
have to use more fuel
380
00:21:16,560 --> 00:21:18,266
to launch the weight
of the other fuel,
381
00:21:18,290 --> 00:21:20,236
and so on and so on.
382
00:21:20,260 --> 00:21:23,776
You have to keep to
an absolute minimum
383
00:21:23,800 --> 00:21:26,476
the amount of weight
you try to launch from earth.
384
00:21:26,500 --> 00:21:29,986
So if NASA wants to set up
residence on Mars,
385
00:21:30,010 --> 00:21:34,116
astronauts will need to find
a water source.
386
00:21:34,140 --> 00:21:38,026
Even though no liquid water
exists on the planet's surface,
387
00:21:38,050 --> 00:21:41,356
there are other places to look.
388
00:21:41,380 --> 00:21:43,826
It turns out there
is a lot of water on Mars.
389
00:21:43,850 --> 00:21:46,166
It's trapped underneath
the ground beneath the dirt
390
00:21:46,190 --> 00:21:47,896
and the soils at high latitudes.
391
00:21:47,920 --> 00:21:51,690
It's also found in huge volumes
up at the polar ice caps.
392
00:21:54,460 --> 00:21:56,076
Ice... you melt,
and it becomes water.
393
00:21:56,100 --> 00:21:57,476
You can drink it.
Yay.
394
00:21:57,500 --> 00:21:59,476
You can grow plants
and do things like that.
395
00:21:59,500 --> 00:22:02,376
In fact, if you were to melt
all of Mars' polar ice,
396
00:22:02,400 --> 00:22:06,956
then you would be able
to cover the globe in water
397
00:22:06,980 --> 00:22:11,426
so ice is an extremely important
thing to have access to.
398
00:22:11,450 --> 00:22:15,296
So if we do go to Mars
to explore and live there,
399
00:22:15,320 --> 00:22:20,396
following the ice
is the way it's going to go.
400
00:22:20,420 --> 00:22:23,266
Even if NASA's astronauts
can turn the martian ice
401
00:22:23,290 --> 00:22:28,036
into drinking water,
without another resource,
402
00:22:28,060 --> 00:22:31,876
settlers will be dead
in three minutes...
403
00:22:31,900 --> 00:22:34,776
oxygen to breathe.
404
00:22:34,800 --> 00:22:37,616
There is oxygen on Mars,
but it's not in the air.
405
00:22:37,640 --> 00:22:38,846
You can't breathe it.
406
00:22:38,870 --> 00:22:42,416
It's bound up in the dirt
and combined with iron
407
00:22:42,440 --> 00:22:47,196
to make iron oxide, giving it
its characteristic red color.
408
00:22:47,220 --> 00:22:49,256
And so we need
to bring it with us,
409
00:22:49,280 --> 00:22:50,926
and that's a huge amount
to bring,
410
00:22:50,950 --> 00:22:55,366
or we need to make it at Mars,
and that's really difficult.
411
00:22:55,390 --> 00:22:59,066
We can deliver oxygen
to the I.S.S.,
412
00:22:59,090 --> 00:23:01,806
but the trip to Mars is long
413
00:23:01,830 --> 00:23:05,876
so there will be
few supply missions.
414
00:23:05,900 --> 00:23:08,076
Once you're on Mars,
you can't pull out your app
415
00:23:08,100 --> 00:23:10,816
and order an oxygen delivery
to your door.
416
00:23:10,840 --> 00:23:13,240
You got to take it with you,
and that's a lot of oxygen.
417
00:23:14,980 --> 00:23:17,056
NASA astronauts will need a way
418
00:23:17,080 --> 00:23:19,826
to make oxygen
on the red planet,
419
00:23:19,850 --> 00:23:22,950
and the space agency
is working on a solution.
420
00:23:26,420 --> 00:23:30,236
When their 2020 rover arrives
on Mars, it will carry out
421
00:23:30,260 --> 00:23:35,506
the Mars oxygen in-situ resource
utilization experiment,
422
00:23:35,530 --> 00:23:38,276
or M.O.X.I.E.
423
00:23:38,300 --> 00:23:42,676
M.O.X.i.e. Will take carbon
dioxide from the martian air.
424
00:23:42,700 --> 00:23:47,856
And use electricity to split
that CO2 and release oxygen
425
00:23:47,880 --> 00:23:51,256
that astronauts could breathe
in the future.
426
00:23:51,280 --> 00:23:54,656
This test will create oxygen
on another planet
427
00:23:54,680 --> 00:23:56,296
for the first time,
428
00:23:56,320 --> 00:24:00,596
but M.O.X.I.E. Can't make enough
for a crewed mission to Mars.
429
00:24:00,620 --> 00:24:02,036
Will be able to make
430
00:24:02,060 --> 00:24:06,606
about half a pound
of oxygen per day,
431
00:24:06,630 --> 00:24:11,546
which is only enough to keep a
human alive for about six hours.
432
00:24:11,570 --> 00:24:15,346
NASA needs to significantly
scale up the technology
433
00:24:15,370 --> 00:24:19,316
to support a whole crew on Mars.
434
00:24:19,340 --> 00:24:24,556
But even if the astronauts
can survive on the red planet,
435
00:24:24,580 --> 00:24:27,826
can they actually reach it?
436
00:24:27,850 --> 00:24:31,526
This is a long trip in a bathtub
with three other people.
437
00:24:31,550 --> 00:24:33,236
It's really challenging.
438
00:24:33,260 --> 00:24:35,036
I think we're still
asking ourselves this question,
439
00:24:35,060 --> 00:24:36,290
how will we do it?
440
00:24:50,210 --> 00:24:53,316
♪
441
00:24:53,340 --> 00:24:57,986
NASA plans to put boots on Mars.
442
00:24:58,010 --> 00:25:02,020
To achieve this, you need
to carry a lot of stuff.
443
00:25:03,650 --> 00:25:06,336
You need oxygen,
you need medical supplies,
444
00:25:06,360 --> 00:25:08,236
you need food,
you need stores of water,
445
00:25:08,260 --> 00:25:11,206
you need some fuel
if you want to come back,
446
00:25:11,230 --> 00:25:16,560
and all this has to be packed
into an incredibly tiny volume.
447
00:25:18,370 --> 00:25:21,246
NASA's solution... Orion,
448
00:25:21,270 --> 00:25:27,016
a 28-ton spacecraft nearly twice
the mass of a school bus.
449
00:25:27,040 --> 00:25:29,156
The rocket that launches Orion
450
00:25:29,180 --> 00:25:33,926
will need to produce
millions of pounds of thrust,
451
00:25:33,950 --> 00:25:36,056
and that is a problem.
452
00:25:36,080 --> 00:25:37,796
If we decided tomorrow, like,
453
00:25:37,820 --> 00:25:40,566
"hey, you know what?
Let's go to Mars."
454
00:25:40,590 --> 00:25:41,836
We can't.
455
00:25:41,860 --> 00:25:43,720
We don't have powerful-enough
rockets to do it.
456
00:25:45,790 --> 00:25:49,436
In 1969, NASA's Saturn V rocket
457
00:25:49,460 --> 00:25:52,046
fired Apollo astronauts
to the moon
458
00:25:52,070 --> 00:25:55,476
with 7.6 million pounds
of thrust.
459
00:25:55,500 --> 00:25:59,586
That's the power of more
than 34 jumbo jets.
460
00:25:59,610 --> 00:26:03,786
A Saturn V could have sent
astronauts to Mars.
461
00:26:03,810 --> 00:26:07,426
Not anymore.
We stopped making them.
462
00:26:07,450 --> 00:26:09,866
To break free
from earth's gravity,
463
00:26:09,890 --> 00:26:14,090
the space rocket must travel
at 25,000 miles an hour.
464
00:26:15,320 --> 00:26:16,636
To achieve that,
465
00:26:16,660 --> 00:26:20,706
NASA is building the most
powerful rocket in the world.
466
00:26:20,730 --> 00:26:23,276
The Space Launch System,
or S.I.S., is the rocket
467
00:26:23,300 --> 00:26:26,176
that's being designed
to carry Orion off of earth
468
00:26:26,200 --> 00:26:28,216
and beyond low earth orbit.
469
00:26:28,240 --> 00:26:31,386
And the philosophy is, "hey,
remember those big rockets
470
00:26:31,410 --> 00:26:33,856
that we used to make back
in the '60s and stuff?
471
00:26:33,880 --> 00:26:36,910
Let's do that again
but more so."
472
00:26:39,250 --> 00:26:40,396
It's really big.
473
00:26:40,420 --> 00:26:42,156
It's larger than
the Saturn V rocket
474
00:26:42,180 --> 00:26:44,696
that was built to carry
the Apollo spacecraft
475
00:26:44,720 --> 00:26:48,996
and is therefore going to be
the largest rocket built.
476
00:26:49,020 --> 00:26:51,536
The space launch system
will be taller
477
00:26:51,560 --> 00:26:53,236
than the statue of Liberty.
478
00:26:53,260 --> 00:26:56,036
Its gargantuan engines
will thrust the rocket
479
00:26:56,060 --> 00:26:57,706
through the atmosphere
480
00:26:57,730 --> 00:27:01,676
with the horsepower
of 160,000 corvettes,
481
00:27:01,700 --> 00:27:05,986
producing 8.8 million pounds
of thrust.
482
00:27:06,010 --> 00:27:11,126
The s.I.S. Will be able to blast
the Orion capsule into space
483
00:27:11,150 --> 00:27:14,280
and send it on its way to Mars.
484
00:27:17,150 --> 00:27:21,166
Unfortunately, the rocket
has fallen behind schedule.
485
00:27:21,190 --> 00:27:26,006
Its maiden test flight was set
for December of 2017.
486
00:27:26,030 --> 00:27:30,706
Now it's scheduled
for the end of 2020.
487
00:27:30,730 --> 00:27:34,546
Critics see the s.I.S.
As a waste of money,
488
00:27:34,570 --> 00:27:38,710
with the project reported to be
billions of dollars over budget.
489
00:27:41,480 --> 00:27:44,426
It's still hoped
NASA's space-launch system
490
00:27:44,450 --> 00:27:49,396
will go to Mars in the 2030s.
491
00:27:49,420 --> 00:27:52,426
But even though the red planet
is our neighbor,
492
00:27:52,450 --> 00:27:56,606
the timing of our visit
will be complicated.
493
00:27:56,630 --> 00:27:58,206
If you're planning
a family vacation
494
00:27:58,230 --> 00:28:00,276
and you want to get in the car,
it's easy, right?
495
00:28:00,300 --> 00:28:02,636
You look at a map
and you say I live in city "a"
496
00:28:02,660 --> 00:28:03,846
and I want to go to city "B"
497
00:28:03,870 --> 00:28:05,876
and I'll just take
the highways there."
498
00:28:05,900 --> 00:28:07,016
Well, great.
499
00:28:07,040 --> 00:28:09,476
Now imagine that city "a"
is moving this way
500
00:28:09,500 --> 00:28:10,846
at 50 miles per hour,
501
00:28:10,870 --> 00:28:13,786
and this city is moving this way
at 200 miles per hour.
502
00:28:13,810 --> 00:28:14,916
Now what do you do?
503
00:28:14,940 --> 00:28:17,226
Well, that is a very
small problem
504
00:28:17,250 --> 00:28:19,726
compared to getting
to another planet.
505
00:28:19,750 --> 00:28:21,396
The timeline of a Mars mission,
506
00:28:21,420 --> 00:28:22,656
the scheduling, if you will,
507
00:28:22,680 --> 00:28:24,366
is all governed
by celestial mechanics,
508
00:28:24,390 --> 00:28:25,566
the orbits of the planets.
509
00:28:25,590 --> 00:28:27,966
It's not just
you pick a time to go to Mars
510
00:28:27,990 --> 00:28:29,936
randomly
whenever you feel like going.
511
00:28:29,960 --> 00:28:31,066
You've literally got to wait
512
00:28:31,090 --> 00:28:33,906
for the planets
to be aligned, right?
513
00:28:33,930 --> 00:28:36,236
On average, the distance
from the earth to Mars
514
00:28:36,260 --> 00:28:38,606
is about 140 million miles.
515
00:28:38,630 --> 00:28:40,116
But this is changing
all the time
516
00:28:40,140 --> 00:28:42,646
because we are both plants
that are orbiting the sun.
517
00:28:42,670 --> 00:28:45,716
So about the closest
that earth ever comes to Mars
518
00:28:45,740 --> 00:28:48,580
is a distance of about
35 million miles.
519
00:28:52,010 --> 00:28:54,496
But on other times
when we're on the opposite side
520
00:28:54,520 --> 00:28:55,756
of the sun from Mars,
521
00:28:55,780 --> 00:28:58,996
it can be as much
as 250 million miles.
522
00:28:59,020 --> 00:29:00,196
Launching near the time
523
00:29:00,220 --> 00:29:05,406
of Mars' closest approach
shortens the journey
524
00:29:05,430 --> 00:29:08,736
so NASA can save on fuel
and resources,
525
00:29:08,760 --> 00:29:12,676
boosting the mission's
chances of success,
526
00:29:12,700 --> 00:29:18,546
but this planetary alignment
only happens every 26 months.
527
00:29:18,570 --> 00:29:21,716
So if NASA misses
a launch window,
528
00:29:21,740 --> 00:29:25,426
it'll have to wait over
two years for another go.
529
00:29:25,450 --> 00:29:28,780
But simply picking
the right time isn't enough.
530
00:29:32,350 --> 00:29:35,866
Mars and the earth
are both orbiting the sun.
531
00:29:35,890 --> 00:29:40,836
So Orion can't fly
in a straight line to Mars.
532
00:29:40,860 --> 00:29:45,946
Instead, it'll use what's known
as a Hohmann transfer.
533
00:29:45,970 --> 00:29:49,676
What we want to do is sort of
put ourselves on our spacecraft
534
00:29:49,700 --> 00:29:51,416
in orbit around the sun
535
00:29:51,440 --> 00:29:54,116
so we might start right here
on earth,
536
00:29:54,140 --> 00:29:55,816
launch our spacecraft,
537
00:29:55,840 --> 00:29:59,796
and, essentially,
we just make a nice, gentle arc
538
00:29:59,820 --> 00:30:02,196
that's arcing around the sun
539
00:30:02,220 --> 00:30:04,996
so that it can naturally slide
into this orbit
540
00:30:05,020 --> 00:30:07,496
and then end up on Mars.
541
00:30:07,520 --> 00:30:11,136
The journey will take
around 10 months.
542
00:30:11,160 --> 00:30:14,136
To get there quicker means
burning more fuel,
543
00:30:14,160 --> 00:30:16,436
which is not an option.
544
00:30:16,460 --> 00:30:20,076
The Hohmann transfer
keeps fuel usage low
545
00:30:20,100 --> 00:30:22,146
by putting the craft in an orbit
546
00:30:22,170 --> 00:30:25,816
that gradually intersects
with the orbit of Mars
547
00:30:25,840 --> 00:30:29,340
before being captured
by the red planet's gravity.
548
00:30:31,050 --> 00:30:34,856
But the crew will need to get
their direction just right.
549
00:30:34,880 --> 00:30:36,796
The way the orbits work,
550
00:30:36,820 --> 00:30:39,296
you've got to aim a little
bit different direction
551
00:30:39,320 --> 00:30:41,536
from where Mars appears
to be now.
552
00:30:41,560 --> 00:30:44,336
You got to aim for where it's
going to be when you get there.
553
00:30:44,360 --> 00:30:46,636
This has to happen so that
it can naturally slide
554
00:30:46,660 --> 00:30:50,106
into this orbit
and then end up on Mars.
555
00:30:50,130 --> 00:30:51,346
If we miss that precision,
556
00:30:51,370 --> 00:30:54,400
then we just could end up
hurtling out into space.
557
00:30:56,670 --> 00:30:59,286
Even if NASA hit their target.
558
00:30:59,310 --> 00:31:03,540
The crew still has a long
10-month journey in space.
559
00:31:04,580 --> 00:31:08,556
The human body is just simply
not designed
560
00:31:08,580 --> 00:31:10,826
for long-duration space travel.
561
00:31:10,850 --> 00:31:13,566
Space travel can destroy bones,
562
00:31:13,590 --> 00:31:17,090
weaken heart muscles,
and even mess with the mind.
563
00:31:18,890 --> 00:31:22,600
Could a cruise survive
the journey to the red planet?
564
00:31:34,110 --> 00:31:37,726
♪
565
00:31:37,750 --> 00:31:42,080
NASA plans to put humans on Mars
in the 2030s.
566
00:31:44,690 --> 00:31:48,150
Rocket technology will be pushed
to its limits.
567
00:31:50,230 --> 00:31:55,636
But the greatest hurdle
is our own fragile bodies
568
00:31:55,660 --> 00:31:58,906
out there in a spacecraft
between the planets,
569
00:31:58,930 --> 00:32:00,116
all bets are off.
570
00:32:00,140 --> 00:32:04,316
It's going to be
a dangerous trip.
571
00:32:04,340 --> 00:32:07,416
Both hands down
to about the fourth rung up.
572
00:32:07,440 --> 00:32:10,326
When astronaut James Irwin
stood on the moon,
573
00:32:10,350 --> 00:32:12,910
his heart beat irregularly.
574
00:32:15,350 --> 00:32:17,826
Back on earth,
Irwin suffered heart attacks,
575
00:32:17,850 --> 00:32:21,166
which eventually proved fatal.
576
00:32:21,190 --> 00:32:24,166
A 2016 study found
that Apollo lunar astronauts
577
00:32:24,190 --> 00:32:27,376
are four to five times
more likely to die
578
00:32:27,400 --> 00:32:29,676
from cardiovascular disease
579
00:32:29,700 --> 00:32:35,246
than astronauts
who never left earth's orbit.
580
00:32:35,270 --> 00:32:39,686
One cause could be
deep-space radiation.
581
00:32:39,710 --> 00:32:41,656
And the radiation in outer space
582
00:32:41,680 --> 00:32:45,126
won't just be damaging
the heart muscles
583
00:32:45,150 --> 00:32:46,956
but also the nervous system
584
00:32:46,980 --> 00:32:49,880
and astronauts' brains
in outer space.
585
00:32:52,090 --> 00:32:54,936
Astronauts heading to Mars
will face radiation
586
00:32:54,960 --> 00:32:58,336
created in the core of stars.
587
00:32:58,360 --> 00:33:02,036
Some comes from our sun
when solar ejections
588
00:33:02,060 --> 00:33:05,276
throw out streams of deadly
charged particles.
589
00:33:05,300 --> 00:33:11,246
♪
590
00:33:11,270 --> 00:33:16,156
There are also cosmic rays
from outside the solar system.
591
00:33:16,180 --> 00:33:20,756
Created in supernovas,
the death of giant stars,
592
00:33:20,780 --> 00:33:23,496
these energetic particles
593
00:33:23,520 --> 00:33:27,136
race through the galaxy at
close to the speed of light.
594
00:33:27,160 --> 00:33:29,666
And you don't want to be
exposed to too many of them.
595
00:33:29,690 --> 00:33:32,306
In low doses, it's not a problem
at all, really.
596
00:33:32,330 --> 00:33:35,306
But in high enough doses,
these things penetrate ourselves
597
00:33:35,330 --> 00:33:37,746
and damage our DNA
and over the long term
598
00:33:37,770 --> 00:33:41,970
can cause really bad damage
to human bodies in space.
599
00:33:44,770 --> 00:33:50,626
The longer you stay in space,
the greater the danger.
600
00:33:50,650 --> 00:33:52,086
Remember,
our missions to the moon
601
00:33:52,110 --> 00:33:53,656
were on the order
of a week or two.
602
00:33:53,680 --> 00:33:56,396
A mission to Mars,
at the minimum,
603
00:33:56,420 --> 00:33:58,196
is going to be
something like two
604
00:33:58,220 --> 00:34:00,896
or two-and-a-half years,
probably.
605
00:34:00,920 --> 00:34:07,136
These cosmic bullets can
cause mutations and even cancer.
606
00:34:07,160 --> 00:34:11,276
New research from 2019 suggests
space radiation
607
00:34:11,300 --> 00:34:13,176
will cause memory loss
608
00:34:13,200 --> 00:34:17,686
in one to three astronauts
on a mission to Mars.
609
00:34:17,710 --> 00:34:18,886
And it's not just a problem
610
00:34:18,910 --> 00:34:21,016
of forgetting where
you've left your keys.
611
00:34:21,040 --> 00:34:23,626
Trying to come back in through
the airlock, you do not want
612
00:34:23,650 --> 00:34:26,156
to be forgetting
emergency procedures.
613
00:34:26,180 --> 00:34:28,556
So we're going to have
to really consider,
614
00:34:28,580 --> 00:34:30,926
how do we mitigate
the effects of this radiation
615
00:34:30,950 --> 00:34:34,196
to make it possible
for people to go to Mars
616
00:34:34,220 --> 00:34:37,436
and actually spend some time
without being ill?
617
00:34:37,460 --> 00:34:41,736
So the ship
needs to protect the astronauts.
618
00:34:41,760 --> 00:34:43,136
Well, you think,
"well, I would just,
619
00:34:43,160 --> 00:34:45,306
I don't know, build a spaceship
out of really thick lead.
620
00:34:45,330 --> 00:34:47,516
Like, well, that weighs a lot,
and it turns out
621
00:34:47,540 --> 00:34:50,246
lead doesn't protect you
from this kind of radiation.
622
00:34:50,270 --> 00:34:52,286
You need something else.
623
00:34:52,310 --> 00:34:53,716
Well, there is something else
624
00:34:53,740 --> 00:34:55,116
that protects you
from this radiation,
625
00:34:55,140 --> 00:34:56,686
and that's water.
626
00:34:56,710 --> 00:34:58,056
We need to bring lots
and lots of water
627
00:34:58,080 --> 00:34:59,856
to drink and cook with.
628
00:34:59,880 --> 00:35:02,556
And if we just place
that water in a layer
629
00:35:02,580 --> 00:35:06,196
around our spacecraft,
that can absorb the cosmic rays.
630
00:35:06,220 --> 00:35:08,866
You might think, well,
you're drinking the very water
631
00:35:08,890 --> 00:35:12,406
that using to stop the radiation
that's causing damage to us
632
00:35:12,430 --> 00:35:14,336
won't the water be dangerous
to drink it?
633
00:35:14,360 --> 00:35:16,136
It doesn't really work
quite like that.
634
00:35:16,160 --> 00:35:19,606
You're just taking one
high-speed subatomic particle
635
00:35:19,630 --> 00:35:21,346
and changing it into another one
636
00:35:21,370 --> 00:35:22,976
as it gets captured
by the water.
637
00:35:23,000 --> 00:35:24,960
Water's still gonna be safe
to drink, fortunately.
638
00:35:27,040 --> 00:35:30,610
But even if NASA can shield
its astronauts from radiation...
639
00:35:32,750 --> 00:35:36,396
...space causes other
health issues.
640
00:35:36,420 --> 00:35:39,726
Your bones are starting
to demineralize.
641
00:35:39,750 --> 00:35:41,066
They're getting weak.
642
00:35:41,090 --> 00:35:44,466
You're getting arthritis
even in the prime of your life.
643
00:35:44,490 --> 00:35:47,036
Weightlessness
during a 10-month journey
644
00:35:47,060 --> 00:35:49,676
will thin the astronauts' bones.
645
00:35:49,700 --> 00:35:51,606
Muscles will waste away,
646
00:35:51,630 --> 00:35:55,946
making walking
on landing difficult.
647
00:35:55,970 --> 00:35:57,086
We've evolved.
648
00:35:57,110 --> 00:36:00,456
We've grown up
on a planet with gravity.
649
00:36:00,480 --> 00:36:03,186
And as soon as you're
an astronaut in outer space
650
00:36:03,210 --> 00:36:05,186
floating around
in weightlessness,
651
00:36:05,210 --> 00:36:06,956
it looks like a lot of fun
652
00:36:06,980 --> 00:36:12,096
but, actually, your body is
deteriorating from the inside.
653
00:36:12,120 --> 00:36:16,736
Astronauts need assistance
to walk when returning to earth.
654
00:36:16,760 --> 00:36:20,006
If NASA's Mars crew arrive
on the red planet
655
00:36:20,030 --> 00:36:23,530
in a poor physical state,
they won't be able to function.
656
00:36:29,440 --> 00:36:32,146
Intense exercise regimes
in space
657
00:36:32,170 --> 00:36:35,956
would help the crew
stay fit and healthy.
658
00:36:35,980 --> 00:36:37,356
But we're in the dark
659
00:36:37,380 --> 00:36:40,710
about the full impact
of extended space travel.
660
00:36:44,620 --> 00:36:46,196
On a mission to Mars,
661
00:36:46,220 --> 00:36:50,166
bodies will be pushed
to the extreme.
662
00:36:50,190 --> 00:36:52,136
To say that sending humans
to Mars
663
00:36:52,160 --> 00:36:54,606
is a challenge
would be an understatement.
664
00:36:54,630 --> 00:36:57,406
We could be ahead of ourselves.
665
00:36:57,430 --> 00:36:59,546
Eventually we're going
to lose people doing this,
666
00:36:59,570 --> 00:37:01,546
and that's something
we have to face.
667
00:37:01,570 --> 00:37:04,846
The question is, is it worth it?
668
00:37:04,870 --> 00:37:08,316
But there may not be a choice.
669
00:37:08,340 --> 00:37:11,086
We know that, over time,
670
00:37:11,110 --> 00:37:13,326
this planet
is not going to be habitable.
671
00:37:13,350 --> 00:37:14,596
So we really should consider
672
00:37:14,620 --> 00:37:17,380
if there are places
we can go outside of earth.
673
00:37:30,000 --> 00:37:34,176
♪
674
00:37:34,200 --> 00:37:36,016
NASA's mission to Mars
675
00:37:36,040 --> 00:37:39,186
will be the toughest
undertaking in its history.
676
00:37:39,210 --> 00:37:43,080
The launch from earth will be
a monumental challenge...
677
00:37:45,210 --> 00:37:49,456
...the journey to Mars
filled with danger,
678
00:37:49,480 --> 00:37:52,726
and survival on
the red planet will be a test
679
00:37:52,750 --> 00:37:55,496
unlike anything
NASA has faced before.
680
00:37:55,520 --> 00:37:58,436
It's easy to make a bullet list
681
00:37:58,460 --> 00:38:00,576
of of why going to Mars is hard.
682
00:38:00,600 --> 00:38:02,306
And that's going to be
a long list,
683
00:38:02,330 --> 00:38:04,946
and those bullet points
are going to be scary.
684
00:38:04,970 --> 00:38:08,376
A lot of these
are serious problems.
685
00:38:08,400 --> 00:38:12,140
NASA's mission to Mars
needs to be a success.
686
00:38:14,540 --> 00:38:17,126
Earth is in danger
687
00:38:17,150 --> 00:38:20,256
from climate change
688
00:38:20,280 --> 00:38:22,196
to asteroid strikes
689
00:38:22,220 --> 00:38:23,950
to nuclear destruction.
690
00:38:26,390 --> 00:38:28,966
We need an escape plan.
691
00:38:28,990 --> 00:38:31,406
Earth may just need a lifeboat
in the future.
692
00:38:31,430 --> 00:38:34,076
We are growing very quickly,
693
00:38:34,100 --> 00:38:37,346
and we're using
a lot of our resources.
694
00:38:37,370 --> 00:38:39,476
We're changing the planet.
695
00:38:39,500 --> 00:38:41,676
We're looking for a lifeboat.
696
00:38:41,700 --> 00:38:45,400
Maybe Mars is the closest,
best chance we've got.
697
00:38:47,440 --> 00:38:48,816
Despite the challenges,
698
00:38:48,840 --> 00:38:52,726
NASA's goal is to send
the Orion spacecraft to Mars
699
00:38:52,750 --> 00:38:54,080
in the 2030s.
700
00:38:56,250 --> 00:38:59,696
But to do that,
we need a rehearsal.
701
00:38:59,720 --> 00:39:01,366
I'd love to see us go to Mars.
702
00:39:01,390 --> 00:39:02,766
I would love to go myself.
703
00:39:02,790 --> 00:39:04,506
But it might be nice
to have a little bit of practice
704
00:39:04,530 --> 00:39:06,190
before we try it.
705
00:39:09,600 --> 00:39:14,346
Where better to practice than
a destination closer to home.
706
00:39:14,370 --> 00:39:19,216
The ultimate aim is to get
humans to Mars, and one approach
707
00:39:19,240 --> 00:39:23,256
is to first have a goal of
getting humans back to the moon.
708
00:39:23,280 --> 00:39:27,180
Orion will first make
the shorter trip to the moon.
709
00:39:29,520 --> 00:39:32,766
There are a lot of advantages
to using the moon.
710
00:39:32,790 --> 00:39:35,866
We can test out different
scenarios for operations
711
00:39:35,890 --> 00:39:38,266
we can also
test out technologies
712
00:39:38,290 --> 00:39:42,576
much more close to home, and so
if something were to go awry,
713
00:39:42,600 --> 00:39:44,206
we can much
more easily intervene.
714
00:39:44,230 --> 00:39:45,506
It's a little bit safer.
715
00:39:45,530 --> 00:39:47,216
If we send people to Mars,
716
00:39:47,240 --> 00:39:48,976
you know, it's going to be
a lot harder for us
717
00:39:49,000 --> 00:39:50,840
to help them if they need it.
718
00:39:55,280 --> 00:39:57,556
NASA's Orion moon missions
will be far more
719
00:39:57,580 --> 00:39:59,780
than just a training exercise.
720
00:40:01,880 --> 00:40:06,126
They'll use them to build
a lunar outpost called gateway,
721
00:40:06,150 --> 00:40:10,406
a space station in orbit
around the moon.
722
00:40:10,430 --> 00:40:12,306
It's actually a lot easier
to do that
723
00:40:12,330 --> 00:40:13,706
than trying to build
something on earth
724
00:40:13,730 --> 00:40:16,636
and get it out of earth orbit.
725
00:40:16,660 --> 00:40:20,516
Six planned missions
will build and maintain
726
00:40:20,540 --> 00:40:24,616
a space station
in orbit around the moon.
727
00:40:24,640 --> 00:40:27,216
It will be a proving ground
for the technology
728
00:40:27,240 --> 00:40:31,386
and the science that will
help us get to the red planet.
729
00:40:31,410 --> 00:40:34,396
And once NASA
has ironed out any problems,
730
00:40:34,420 --> 00:40:37,896
the real mission can begin.
731
00:40:37,920 --> 00:40:41,866
Gateway won't simply be
a small step for man.
732
00:40:41,890 --> 00:40:46,106
It'll be a springboard
to another planet.
733
00:40:46,130 --> 00:40:49,106
When we first sent humans
to another planetary body,
734
00:40:49,130 --> 00:40:52,176
it was the moon, and we had
never done that before.
735
00:40:52,200 --> 00:40:54,346
So now we've got the moon
under our belt.
736
00:40:54,370 --> 00:40:57,886
We know something about how to
send people to another planet.
737
00:40:57,910 --> 00:41:01,356
We don't yet have all the
technologies that we might need
738
00:41:01,380 --> 00:41:04,340
to send humans to Mars,
but we're well on our way.
739
00:41:06,380 --> 00:41:09,626
As NASA begins
its journey to the red planet,
740
00:41:09,650 --> 00:41:11,620
not everyone is on board.
741
00:41:13,620 --> 00:41:15,796
A lot of people think of Mars
as our lifeboat
742
00:41:15,820 --> 00:41:17,966
just in case
we screw things up on earth,
743
00:41:17,990 --> 00:41:21,236
but we really need
to take care of our own planet.
744
00:41:21,260 --> 00:41:24,106
If you want to go there
and explore
745
00:41:24,130 --> 00:41:26,506
or build a base,
more power to you.
746
00:41:26,530 --> 00:41:27,976
But I'm going to stay
747
00:41:28,000 --> 00:41:30,846
where it's a little bit
more green and blue.
748
00:41:30,870 --> 00:41:36,216
♪
749
00:41:36,240 --> 00:41:39,726
Even so, NASA is already
building rockets
750
00:41:39,750 --> 00:41:41,796
and testing the technology.
751
00:41:41,820 --> 00:41:47,766
The stage is set for humankind's
greatest adventure.
752
00:41:47,790 --> 00:41:50,936
I think we will send humans
to Mars.
753
00:41:50,960 --> 00:41:53,606
It's just a really, really,
really big problem
754
00:41:53,630 --> 00:41:55,736
that we have to figure out
how to solve.
755
00:41:55,760 --> 00:41:58,306
But we're good
at solving problems.
756
00:41:58,330 --> 00:42:00,746
Given the human mind
and how curious we are
757
00:42:00,770 --> 00:42:03,846
and how much we like
to climb the next mountain
758
00:42:03,870 --> 00:42:07,146
and achieve the next
challenge, Mars is right there.
759
00:42:07,170 --> 00:42:08,556
There is something
in the human psyche
760
00:42:08,580 --> 00:42:11,926
that will send us to Mars
despite all of the challenges.
761
00:42:11,950 --> 00:42:15,696
And so for sure
we will go to Mars.
762
00:42:15,720 --> 00:42:17,926
Even though it's extremely
difficult to go to Mars,
763
00:42:17,950 --> 00:42:19,726
the answer is always yes
764
00:42:19,750 --> 00:42:21,696
if somebody asks me
if we should go
765
00:42:21,720 --> 00:42:23,860
because that's
the ultimate goal.
61187
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