WASHINGTON, Dec. 12, 2012 /PRNewswire-USNewswire/ -- In 2012, NASA continued to implement America's ambitious space exploration program, landing the most sophisticated rover on the surface of Mars, carrying out the first-ever commercial mission to the International Space Station and advancing the systems needed to send humans deeper into space. (Logo: http://photos.prnewswire.com/prnh/20081007/38461LOGO) "NASA achieved historic milestones this year landing the most sophisticated rover on the surface of Mars, carrying out the first ever commercial mission to the space station and continuing to advance the systems needed to send humans deeper into space -- beyond the moon, to an asteroid and on to Mars," NASA Administrator Charles Bolden said. "We are able to keep the United States the world leader in space exploration -- and continue to implement America's bipartisan space plan -- because of our talented and dedicated work force." The following are some of NASA's top stories this year: NASA LANDS CAR-SIZE ROVER BESIDE MARTIAN MOUNTAIN Undertaking the most complex landing ever attempted in planetary exploration, NASA successfully placed the most advanced robotic rover on Mars. The Mars Science Laboratory mission carrying the one-ton rover named Curiosity, touched down in August. Almost immediately, Curiosity sent back pictures of its landing site at Gale Crater with the eventual destination of Mount Sharp in the background. Since then, Curiosity has checked out its 10 science instruments, sent back detailed photos and weather observations and "tasted" Martian soil. Key mission findings during the first three months after the landing include conglomerate rocks bearing rounded pebbles as evidence of vigorous ancient stream flow right in the area where Curiosity landed; mineral composition of Martian soil similar to soils in Hawaii that contain volcanic glass; and the first assessment of the natural radiation environment that future astronauts will encounter on the surface of Mars. Curiosity's planned two-year prime mission will be to explore and assess a local region on the surface of Mars as a potential habitat for life, past or present. In addition, the landing technology for putting such a large payload safely on the Martian surface could help with plans for future human Mars missions.