During the first week of May, the small crew left behind at an
Antarctica research station bid farewell to the sun as it set
for the last time for the season, plunging the frigid continent
into the permanent midnight of winter. The next sunrise will
come about four months from now, when spring returns to the
bottom of the world. Concordia Station, a joint French-Italian
research station, sits in the middle of the East Antarctic Ice
Sheet. It is one of the most isolated spots on Earth — so
isolated, in fact, that it is used as an analog for extended
human spaceflight. When the small band of researchers and
workers now living at Concordia were training for their year-
long deployment, they were told it was easier to escape the
International Space Station than Concordia in winter. When the
temperatures drop, airplanes can't reach the station, and the
crew has been marooned there without a physical link to the
outside world since early this year. Yet now, although they are
no more alone than before, the light has