biology: human body
life on
MARS
One day, humans may colonize the Red
Planet. What will it take to survive there?
O
FUTURE SPACE
COLONY? This
illustration shows
what an outpost on
Mars might look like.
Stephen Morrell/National Geographic Stock
n July 20, 1969, astronauts Neil Armstrong
and Buzz Aldrin became
the first people to set
foot on the moon. The
occasion marked the beginning of
human space exploration. More than
40 years later, scientists have their
sights set on another first: human
colonization of Mars.
SpaceSuit Mars explorers would need a spacesuit to protect them
from dangerous radiation, subzero temperatures, and a lack of oxygen.
Scientists are developing a suit with special features like rear entry from an
RV-style Humvee rover. “You would be able to put the suit on quickly without
entering an airlock and keep the dust outside the rover at all times,” says
Ronald Sidgreaves, an electrical engineer working on the suit.
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march 7, 2011
rover The point of using a rover
is to explore the Martian landscape
from afar. Some of the robot rovers
currently being engineered may look
like oversize remote-control cars, but
they’re a lot more complicated. One,
dubbed K10, is controlled by artificial
intelligence. The robot can use its
“brain” to figure out how to accomplish different tasks. It would help
Mars colonists by being able to go
where humans couldn’t.
But before adventurers blast
off, scientists are doing as much
intelligence gathering as possible
to ensure success.
Closer to Home
Since Mars is millions of miles
away, scientists who are interested
in learning how to colonize the Red
Planet often conduct experiments
greenhouse
Because Mars is so far from Earth, it would be impossible to send fresh food to a Martian colony. Growing crops on Mars would be
critical so astronauts could nourish themselves. “Plants take minerals from the
environment and mobilize them into something that people can use,” explains
Anna-Lisa Paul, a scientist studying plant growth on Devon Island. A Mars-based
greenhouse would simulate ideal growing conditions on Earth.
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NASA already has sent numerous
robotic spacecraft to the Red Planet.
One robot, Phoenix, landed on Mars
in 2008 and was the first mission to
return data from Mars’ poles. It confirmed water ice on the planet.
Most likely, robots will continue
to scout Mars’ surface when the
first explorers are ready to set up a
colony. “Robots can go places that
are very difficult for people to go.
They become a remote extension of
people as we explore the universe,”
says Matthew Deans, who leads the
Haughton robotics team.
Mars explorers will rely on technology similar to that being tested by
Deans’s team. The team has developed
a robot called K10 which operates
using artificial intelligence. K10 is
programmed to solve problems on its
own without any outside instructions.
MARTIAN LANDSCAPE: Satellite
images have revealed an ice cap
on Mars made of water ice and
solid-phase carbon dioxide. In
winter, this cap covers a vast sea
of sand dunes. One day, rovers
may learn more about this region.
CARBONDIOXIDE
FROST
hard, black
basalt sand
DIRECTION OF WIND
SAND DUNE
Far-Out Farming
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march 7, 2011
it useful for testing technology—
like spacesuits, rovers, and greenhouses—that could someday help
astronauts living on Mars.
Suiting Up
In order to survive on the Red
Planet, explorers would need a lightweight, flexible suit that protects them
from the hazards of outer space.
On Mars, the atmosphere is only
0.7 percent that of Earth’s and contains mainly carbon dioxide (see
Earth vs. Mars, right). A spacesuit’s
life-support system has to mimic
Earth’s atmosphere, simulating, for
instance, its air pressure (air molecules in the atmosphere pushing
down). Without this pressure, the
human body’s systems would malfunction, resulting in death.
Spacesuits also must protect
explorers from Mars’ extreme cold
while allowing body heat to escape.
The suits must include an oxygen tank
so astronauts can breathe, and also
protect them from radiation. These
high-energy waves and particles that
come from the sun and space can
damage or kill living cells.
Today’s heavy spacesuits are fine
for current tasks like floating outside
the International Space Station to
make repairs. But they are far from
being compatible with the Martian
environment. Explorers on Mars will
need, for instance, to be able to bend
down and pick up rock samples without toppling over. They’ll need to be
able to suit up quickly and have the
flexibility necessary to drive a rover
over the rough Martian terrain. On
Devon Island, scientists are testing
out NASA’s latest concept suits to see
if they make the grade.
Robotic Explorers
Since the Martian environment is
so inhospitable, it will sometimes be
easier to let robots do the exploring.
left: NASA/JPL/University of Arizona; Top right: NASA/JPL; Bottom right: Justin Dawes/Kawasaki
here on Earth. It’s a lot simpler and
less costly. Pascal Lee, an astrogeologist for NASA, set up a research
station on an isolated island in the
Canadian Arctic in 1997. He chose
the location because of its similarities to Mars. More than a decade
later, it is still a major hub for experiments designed to prepare for future
manned Mars missions.
Devon Island lies 1,600 kilometers
(1,000 miles) from the North Pole.
The surfaces of both Mars and Devon
Island are pitted with meteoriteimpact craters. Both lack plant and
animal life. And while Devon Island’s
weather isn’t nearly as extreme as
Mars’ frigid climate, its cold and
unpredictable conditions make the
island as close as you can get to Mars
on Earth. “We were blown away by
the similarities that exist between this
place and Mars,” says Lee.
The island’s remote location, terrain, and extreme conditions make
Luckily, as Phoenix confirmed,
Mars has a supply of frozen water,
which could sustain colonists. But
with current technology, the journey
to Mars would take two years, making
it impossible to resupply a Martian
base with food from Earth. The ability
to grow food would be an important
step to setting up a permanent base.
TEST DRIVE: Pascal Lee
tries out a spacesuit near
a crater on Devon Island,
a place on Earth that looks
strikingly similar to Mars.
Earth vs. Mars
How does Earth compare with its closest neighbor?
Earth
Mars
24 hours
Day
24 hours, 37 minutes
12,756 km
(7,926 mi)
Diameter
365 days
Year
6,786 km (4,216 mi)
687 days
15°C (59°F) Average temperature -63°C (-81°F)
1 (the Moon)
NATURAL Satellites
70% nitrogen, Atmosphere
21% oxygen
Anna-Lisa Paul, a horticultural
scientist from the University of
Florida, is investigating the effects
of a Marslike environment on plants.
Paul grows crops in a greenhouse
on Devon Island. She uses the local
loose, rocky soil that is similar to the
regolith on Mars. So far, the experi-
2 (Phobos and Deimos)
95% carbon dioxide,
trace amounts of oxygen
ment has yielded some self-sustaining
crops like lettuce.
Are We There Yet?
Research related to colonizing the
Red Planet is ongoing. But an actual
mission to Mars is still years away.
In 2004, the United States
announced plans for a resurgence of
human space exploration, including a
trip to Mars. But those plans have since
changed. As a result, programs such as
a proposed return trip to the moon in
2012—a first step in further exploring
our solar system—were revised.
“The new direction at NASA is to
develop technologies that can lead to
breakthroughs in space travel,” says
Lee. Meanwhile, scientists are busy
making sure that when the U.S. does
decide to send humans to Mars, we’ll
be ready. 9
—Tyrus Cukavac
[video Extra] Watch a video
about Mars exploration at:
www.scholastic.com /scienceworld
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