MARS

says Crusan. They planned to live off the land
once they arrived. That’s exactly what NASA
hopes its astronauts can do.
For years, NASA has been testing
technologies that would help a crew survive
on Mars. For instance, astronauts aboard
the International Space Station, which orbits
402 kilometers (250 miles) above Earth,
currently purify their urine to make water.
They also make air by passing an electric
current through water. The process, called
electrolysis, separates the water molecules
into hydrogen and breathable oxygen gas.
FARAWAY FARMING
In The Martian, Watney encounters a
real problem that any future Mars crew will
face: growing food. Watney uses Martian
soil mixed with his own poop (as fertilizer)
to grow potatoes inside his habitat. “But he
works a lot harder than he needs to,” says
Green. He explains that Watney probably
could have relied more on Martian soil,
because the rover Curiosity recently detected
much more water and nitrogen in the soil on
Mars than previously expected. “Nitrogen is a
great fertilizer,” he says.
To get enough water for the food that he’s
growing, Watney extracts water from rocket
fuel. But Green explains that rovers have
recently discovered a
layer of ice not far from
the surface of Mars in a
region named Acidalia
Planitia—which is
right where Watney is
stationed. “He could
have just detonated
an explosive and then
picked up the ice chips,”
says Green.
MARTIAN HOME
Besides food, water,
and oxygen, living
long-term on Mars will
also require shelter that
can protect colonizers
from the harsh Martian environment (see Life
on Mars, below). Earth’s atmosphere keeps
our planet’s temperatures from fluctuating
too drastically and protects us from the
sun’s radiation. But the blanket of gases
surrounding Mars is thin. Temperatures there
dip to an average of -70°C (-94°F).
It’s hard to know how humans will survive
in these conditions until we actually get
there. But thanks to NASA’s efforts, someone
like Watney just might stand a chance alone
on the Red Planet. 9 — Andrew Klein
MARS WRITING CONTEST
Imagine that you’re on the first mission
to Mars and you discover a colony of
intelligent life-forms. Let’s say you could
communicate with them. Compare and
contrast Mars and Earth so that the
Martians understand how the two planets
are similar and different. Five winners will
get signed copies of Welcome to Mars
by astronaut Buzz Aldrin, the
second astronaut to walk
on the moon, in 1969. Go
to scholastic.com
/scienceworld for more
details about how to enter.
Click here
in our digital
issue for entry
form and
contest rules.
LIFE ON MARS
Here’s what the astronauts’ colony might look like.
WORKSPACE
An inflatable structure
serves as a place to
do experiments.
UNDERGROUND
LIVING
Underground living
quarters protect
astronauts from the
sun’s radiation.
ROVERS
Astronauts will
drive their vehicles
to different
locations to
conduct studies.
GREENHOUSE
In one system being
tested, plants grow
in water fertilized by
fish droppings.
BRYAN VERSTEEG/SPACEHABS.COM (ALL ILLUSTRATIONS)
22 OCTOBER 26, 2015