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from JupiterOceanPlumeMo
lec
ules(^) bre
ak down
H 2 N
O
OH
NH^2
O
OH
NH 2
O
OH
NH 2
O
OH
H^2 N
O
OH
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O
OH
NH 2
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OH
O
H 2 N
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O
H
2 N
OH
H 2 N OH
O
O
NH 2
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NH 2 OH O
NH 2 OH
NH 2 OH
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Surface
Material
from ocean
WWW.ASTRONOMY.COM 33
“Biologists still struggle to put a defi-
nition on what is alive and what is not
alive,” says Curt Niebur, a scientist at
NASA Headquarters in Washington,
D.C. “It’s hard enough [searching for life]
on Earth, so doing that halfway across
the solar system with a robotic spacecraft
is even more difficult, more complicated,
and more challenging.”
Because of the seemingly uninhabitable
surface conditions, any probe sent to the
moon would theoretically have to drill
down some unknown distance before
sampling for life. Scientists are working
on ways to achieve this, but in the near
future, they’ll only be able to take mea-
surements remotely.
Niebur is working on just that as the
program scientist for NASA’s Europa
Clipper mission, which aims to launch in
- By studying the moon in detail, the
mission will determine whether Europa
has conditions suitable for life.
EUROPA’S SURFACE could show signs of life if material containing biomolecules is ejected by the
moon’s plumes. But because intense radiation from Jupiter breaks down materials on the surface, those
signs could be erased, which is why researchers hope to take a direct picture of life rather than detect it
through surface composition. ASTRONOMY: ROEN KELLY
EUROPA’S ICY CRUST contains a wealth of
interesting topography that hints at the moon’s
geologic past. This close-up image of the terrain,
taken by the Galileo spacecraft, shows ridges,
domes, and a jumbled area of “ice rafts” that
scientists think broke away from their original
locations. The smashed-up blocks of terrain are
a compelling sign that the moon once had a liquid
ocean. NASA/JPL/UNIVERSITY OF ARIZONABREAKING IT DOWN