Expedition 46 Commander Scott Kelly of NASA is seen after returning to Ellington Field, Thursday, March 3, 2016 in Houston, Texas after his return to Earth the previous day. via NASA http://ift.tt/1p1pcaC

Astronaut Scott Kelly Returns to Houston after a Year in Space via NASA http://ift.tt/1Skeya6

The Soyuz TMA-18M spacecraft is seen as it lands with Expedition 46 Commander Scott Kelly of NASA and Russian cosmonauts Mikhail Kornienko and Sergey Volkov of Roscosmos near the town of Zhezkazgan, Kazakhstan on Wednesday, March 2, 2016 (Kazakh time). via NASA http://ift.tt/1Lw1RaL

NASA astronaut Scott Kelly shared a series of five sunrise photographs on Tuesday, March 1, 2016, as he prepared to depart the space station and return to Earth aboard a Soyuz TMA-18M spacecraft. Kelly and Russian cosmonauts Mikhail Kornienko and Sergey Volkov are scheduled to undock their Soyuz at 8:02 p.m. EST and land at 11:25 p.m. via NASA http://ift.tt/1LSMWSJ

Although Tethys and Janus both orbit Saturn and are both made of more or less the same materials, they are very different worlds. via NASA http://ift.tt/1RftqBR

The distinctive blue bubble appearing to encircle WR 31a is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases. Created when speedy stellar winds interact with the outer layers of hydrogen ejected by Wolf–Rayet stars, these nebulae are frequently ring-shaped or spherical. via NASA http://ift.tt/1oEvGez

NASA research mathematician Katherine Johnson is photographed at her desk at Langley Research Center in 1966. Johnson made critical technical contributions during her career of 33 years, which included calculating the trajectory of the 1961 flight of Alan Shepard. She was awarded the Presidential Medal of Freedom on Nov. 24, 2015. via NASA http://ift.tt/1QgSqsn

Expedition 46 crew member Tim Peake of the European Space Agency (ESA) shared a stunning image of a glowing aurora taken on Feb. 23, 2016, from the International Space Station. Peake wrote, “The @Space_Station just passed straight through a thick green fog of #aurora…eerie but very beautiful. #Principia” via NASA http://ift.tt/1Qyiuyk

This image, acquired by the Operational Land Imager (OLI) on Landsat 8, shows the glaciers of Sierra de Sangra on Jan. 14, 2015. Snow and ice are blue in these false-color images, which use different wavelengths to better differentiate areas of ice, rock, and vegetation. via NASA http://ift.tt/1T4g2qg

Three of Saturn’s moons — Tethys, Enceladus and Mimas — are captured in this group photo from NASA’s Cassini spacecraft. via NASA http://ift.tt/1PSmkVP