NASA successfully launched a set of twin spacecraft into orbit today (Sept. 10) to study the moon’s gravity, but the new mission isn’t the first — or the last — robotic planetary expedition for the space agency year.

Fire and smoke light up a blue sky as a United Launch Alliance Delta 2 Heavy rocket propels NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission into space. Liftoff from Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida was at 9:08:52 EDT Sept.10, 2011 CREDIT: NASA/Darrell McCall
The two Grail spacecraft launched toward the moon from Florida’s Cape Canaveral Air Force Station to begin a 3 1/2-month trip to lunar orbit. The liftoff came just one month after another NASA observatory launched toward Jupiter to study the gas giant’s composition and atmosphere. That flight, the Juno mission to Jupiter, is also expected to beam back the best photos yet of the solar system’s largest planet.
“Today we had the second of NASA’s planetary science launches in what we’ve been calling the ‘Year of the Solar System,’” Jim Adams, deputy director of the planetary science division at NASA Headquarters in Washington, D.C., told reporters in a post-launch news briefing. “Just over a month ago, Juno was thrust on its way off to Jupiter, and today we sent a set of twin spacecraft off to the moon.” [Photos: NASA Launches Grail Probes to the Moon]
The $1.1 billion Juno mission is expected to arrive at the giant planet in July 2016.



