SpaceX's Dragon spacecraft atop rocket Falcon 9 lifts off from Cape Canaveral in Florida in May 2012. The launch made SpaceX the first commercial company to send a spacecraft to the International Space Station. Roberto Gonzalez/Getty Images hide caption

itoggle caption Roberto Gonzalez/Getty Images

The Chinese flag is seen in front of a view of the moon at Beijing's Tiananmen Square in December, when China's first moon rover touched the lunar surface. That feat was widely celebrated — but observers believe the rover has now run into serious trouble. Mark Ralston/AFP/Getty Images hide caption

itoggle caption Mark Ralston/AFP/Getty Images

Tracks from NASA's Opportunity rover disappear toward the horizon on the Meridiani Plains of Mars. The rover has been on the planet since 2004. NASA/JPL-Caltech/Cornell University hide caption

itoggle caption NASA/JPL-Caltech/Cornell University

Kepler-22b, seen in this artist's rendering, is a planet a bit larger than Earth that orbits in the habitable zone of its star. Some researchers think there might be "superhabitable" worlds that may not resemble Earth. NASA/Ames/JPL-Caltech hide caption

itoggle caption NASA/Ames/JPL-Caltech

This composite image shows new details of the aftermath of a massive star that exploded and was visible from Earth over 1,000 years ago. Chandra X-ray Observatory Center/NASA hide caption

itoggle caption Chandra X-ray Observatory Center/NASA

Live, from the moon, it's the space weather report: Data from a lunar orbiter is being used to create a music stream that reflects conditions in space. Here, an image created by NASA "visualizers" who used data from 2010 to show the moon traveling across the sun, as happens two or three times a year. NASA/SDO/LRO/GSFC hide caption

itoggle caption NASA/SDO/LRO/GSFC

Coming At You: An image created by NASA combines two pictures from its Solar Dynamics Observatory. One shows the location of a large sunspot; the other shows Tuesday's massive solar flare. NASA/SDO hide caption

itoggle caption NASA/SDO