This artist rendering shows Kepler-11, a sun-like star around which six planets orbit. A planet-hunting telescope is finding whole new worlds of possibilities in the search for alien life, including more than 50 potential planets that initially appear to be in habitable zones. The agency's chief scientist said Tuesday there will be "strong indications" of alien life within a decade. NASA/AP hide caption

itoggle caption NASA/AP

NASA astronaut Scott Kelly is seen inside a Soyuz simulator at the Gagarin Cosmonaut Training Center on March 4 in Star City, Russia. Kelly, along with Russian cosmonaut Mikhail Kornienko of the Russian Federal Space Agency, are scheduled for launch Friday aboard a Soyuz TMA-16M spacecraft from the Baikonur Cosmodrome in Kazakhstan. NASA/Bill Ingalls hide caption

itoggle caption NASA/Bill Ingalls

An image of Ceres taken by NASA's Dawn spacecraft shows that the brightest spot on the dwarf planet has a dimmer companion. NASA/JPL-Caltech/UCLA/MPS/DLR/IDA hide caption

itoggle caption NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

An image taken with the NASA/ESA Hubble Space Telescope of the galaxy cluster SDSS J1038+4849 shows that it seems to be smiling. The space agency says it's the result of a symmetrical alignment of the galaxy cluster and the telescope — along with a powerful gravity field that can bend light. NASA & ESA hide caption

itoggle caption NASA & ESA

Leland Melvin with his dogs, Jake and Scout. "I snuck them into NASA to get this picture," Melvin says. Courtesy of Leland Melvin hide caption

itoggle caption Courtesy of Leland Melvin