An artist's depiction of the twin spacecraft that comprise NASA's Gravity Recovery And Interior Laboratory (GRAIL) mission. During the GRAIL mission's science phase, spacecraft (Ebb and Flow) transmit...› View Image
An artist’s depiction of the twin spacecraft (Ebb and Flow) that comprise NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission.
NASA's Jet Propulsion Laboratory in Pasadena, Ca...
This image of the far side of the lunar surface, with Earth in the background, was taken by the MoonKAM system onboard the Ebb spacecraft as part of the first image set taken from lunar orbit from Mar...› View Image
This image of the lunar surface was taken by the MoonKAM system onboard the Ebb spacecraft on March 15, 2012. The 42.3-mile-wide (68-kilometer-wide) crater in the middle of the image (with the smaller...› View Image
Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field.
The mission also will answer longstanding questions about Earth's moon, includin...
Artist concept of GRAIL mission.
Image credit: NASA/JPL-Caltech
NASA's GRAIL twin spacecraft await launch atop a United Launch Alliance Delta II rocket at Cape Canaveral Air Force Station, Fla.
Image credit: NASA/JPL-Caltech/United Launch Alliance, Th...
These images show the various stages of pre-launch preparations of NASA's twin GRAIL spacecraft at Space Launch Complex 17B on Cape Canaveral Air Force Station in Florida.
Image credit: N...
At Astrotech Space Operation's payload processing facility in Titusville, Fla., NASA's Gravity Recovery and Interior Laboratory-A (GRAIL-A) lunar probe is lifted from its workstand and across the clea...› View Image
Using a precision formation-flying technique, the twin GRAIL spacecraft will map the moon's gravity field, as depicted in this artist's rendering. Radio signals traveling between the two spacecraft pr...› View Image
NASA's lunar twins arrive at Cape Canaveral, Fla. The two GRAIL spacecraft (GRAIL-A and GRAIL-B) made the trip from the Denver area to the Shuttle Landing Strip at the Kennedy Space Center, Fla. on Ma...› View Image
In the photo, taken April 29, 2011, technicians install lifting brackets prior to hoisting the 200-kilogram (440-pound) GRAIL-A spacecraft out of vacuum chamber after testing. Along with its twin GRAI...› View Image
Engineers conduct checks on one of NASA's GRAIL spacecraft in the Space Support Building at Lockheed Martin Space Systems in Denver.
Image credit: NASA/JPL/LockheedMartin