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Of all the tools a planetary scientist uses to study other worlds,
comparing features found on different planets and moons is
one of the most powerful. For instance, the layering seen in
Icelandic glaciers bears a strong resemblance to those in the
polar caps of Mars, and volcanic f lood plains in Africa have
similar counterparts on Venus. Scientists also study terrestrial
analogues to the strange landscapes of the outer solar system.
Pressure ridges and fractures in sea ice on Earth share a kinship
with those found on Jupiter’s moon Europa, for example.
The world’s southernmost active volcano, Antarctica’s
Mount Erebus, may provide insights into Saturn’s geyser-
spewing moon, Enceladus, as well as to other volcanic ice
worlds. To that end, the two of us — planetary volcanologist
Rosaly Lopes and space artist and writer Michael Carroll —
traveled to Antarctica in search of icy analogues on the f lanks
of the 12,448-foot (3,794 meters) peak. At times, however,
getting to the mountain seemed almost as difficult as getting
to the outer solar system.
A planetary outpost on Earth
For a preview of what a future Mars settlement might look like,
it’s hard to beat the U.S. Antarctic Program’s McMurdo Station.
Sitting on Ross Island next to the vast Ross Ice Shelf and sur-
rounded by a harsh, exotic terrain, McMurdo is a settlement
where people recognize the hostile nature of their location. The
station’s double doors are arranged like airlocks, equipped with
latching handles to protect against the strong Antarctic winds.
All travel — whether by foot, snowmobile, tractor, or aircraft
— must be registered, and radio communication is constantly
monitored. The environment just outside McMurdo’s perimeter
is so dangerous that lines of f lags have been erected to help
people find their way home in storms.
A soft blue light suffuses through the beautiful
but treacherous caves beneath Ice Tower Ridge. MICHAEL CARROLL
Left: Deep furrows near the south pole of Saturn’s moon
Enceladus are sites of cryovolcanic activity that might bear
some resemblance to Antarctica’s Mount Erebus. NASA/JPL/SSI
