This image, taken from inside the International Space Station (ISS), depicts the aurora australis, aka the southern lights.
Doug Hurley, pilot of the docked shuttle Atlantis, who witnessed the greenish glow from the multi-windowed cupola that was carried up via shuttle and added to the ISS last year, told the press that it was "the best [aurora] I've seen in my two spaceflights."
In a 2005 Scientific American article about the asymmetry of the Earth's auroras, Sarah Graham explained that the southern lights—and their more famous Northern Hemisphere cousin, the aurora borealis, or northern lights—"result from the interaction between Earth's magnetic field...and energized particles from the solar wind that emit light in the upper atmosphere."
On the day this photo was taken, the STS 135 and Expedition 28 crew members were wrapping up NASA's final space shuttle mission. Atlantis is docked on the right, and the Orbiter Boom Sensor it uses to check its reentry tiles hangs over the center. The solar array at left is a small sliver of the 3,570 square meters of solar panels that generate up to 120 kilowatts of power for the ISS.
Atlantis is scheduled to land at the Kennedy Space Center at 5:56 A.M. Eastern time Thursday.
—Lauren F. Friedman