Page 107 - How It Works - Book Of Amazing Answers To Curious Questions, Volume 05-15

Space

What is the aim of NASA’s

Europa mission? Here’s why Jupiter’s icy moon

is next on NASA’s hit list

n May, following federal allocation of
funds for the coming year, NASA Icy world explorer Orbital resonance
Iannounced the selection of a series of What can we expect to see Ganymede, Europa and
Io orbit Jupiter in such a
scientific instruments it would use to from our first trip to Europa? way that Io makes four
investigate potential life on an icy moon, along orbits in the time it
takes Europa to make
with a 2020s mission to Europa. This is one of two and Ganymede to
Jupiter’s largest natural satellites and, make one.
courtesy of its role in various science fiction
novels and films, perhaps one of the most
famous objects in the Solar System.
Europa isn’t just the next logical stepping-
stone from Mars into the outer Solar System
though: it’s a frozen world at the surface with
an icy crust, and there’s strong evidence for a
large sub-surface water ocean beneath it. In
many ways it’s a remarkably similar place to
the lakes found beneath the kilometres-thick
ice of Antarctica, where several space agencies
(including NASA) have conducted experiments
for years, so this isn’t a wholly alien
environment to us. Furthermore, life has been
found in sub-surface Antarctic lakes that have
been devoid of any sunlight for tens of
thousands, or even millions of years. This Thick crust
Europa is coated in a
means Europa has the potential to be water-ice crust that
habitable, even if life never occurred on it. could be up to 25km
(15.5mi) thick. Peer pressure
The current proposal is for a hardy probe Jupiter’s massive
that can withstand the intense radiation belts Grand canyons gravitational influence
flexes the moon’s
around Jupiter to make the 600 million- Tidal interactions with interior, producing
Jupiter generate stresses in
kilometre (373 million-mile) journey to the gas Debut mission the icy crust, creating wide enough heat to enable
giant. Here it will orbit Jupiter and perform 45 Our first trip to Europa is and deep fractures. liquid water to exist
a kind of reconnaissance beneath the surface.
flybys of Europa – swooping as low as 25 mission that will launch
kilometres (16 miles) above the surface – in the 2020s.
scanning the moon to determine the
thickness of the ice and where its subsurface
lakes might be found. If the reconnaissance Multiple flybys
A proposed 45 flybys of
mission is a success, scientists could follow up Europa will be conducted to
with a landing mission and a probe to send avoid prolonged exposure to
strong radiation.
beneath the ice crust to search for life in the
frigid depths.
What is the squid rover?

NASA’s calling it the ‘Soft-Robotic Rover with to provide the fuel for its propulsion systems, as well
Electrodynamic Power Scavenging’ – but the concept as generating electricity for both communications and
of this aquatic rover was inspired by the squid and so alien life-seeking scientific instruments.
the catchier ‘squid rover’ has stuck. It certainly This technology is very much in the concept phase,
resembles this terrestrial mollusc. but NASA is taking its development seriously. If
The squid rover will plummet into the dark and cold successful, the squid rover would solve the problem of
depths of Europa’s sub-surface oceans, where no powering a craft so far away from the Sun. On top of
nuclear or solar-powered rover can hope to survive. It that, it would be an effective propulsion system
will ‘scavenge’ its power from its environment, using through the sub-surface oceans, which are suspected
This soft-bodied rover will search for
two tentacle-like appendages to electrolyse the water to lie beneath the icy surface of many outer Solar habitable environments in sub-surface
around it. It will then produce hydrogen and oxygen gas System worlds. oceans on other worlds © NASA

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