
Mission Details
Mission Name: GRAIL |
Mission Type: Lunar Orbiter |
Operator: NASA (National Aeronautics and Space Administration) |
Launching State: United States |
Location: Between Philollaus & Mouchez Craters |
Latitude: 75.609 |
Longitude: -26.593 |
Launch Date: 20 September 2011, 13:08:52 UT |
Landing Date: 17 December 2012, 22:28:51 UT |
Objects on or Related to Site: GRAIL A |
Image Source: NASA |
Description
GRAIL’s twin spacecraft studied the internal structure and composition of the Moon in unprecedented detail for nine months and produced a detailed gravitational map of the Moon.
Read more:
https://solarsystem.nasa.gov/missions/grail/in-depth/
Heritage Consideration
NASA’s GRAIL mission flew twin spacecraft—Ebb and Flow—in tandem around the Moon to map variations in the lunar gravitational field. The probes generated the highest resolution gravity map of any celestial body to date. At the end of the mission, the probes were purposely crashed on the Moon.
Object on or Related to Site
Object Name: GRAIL A & B | |
Cospar: 2011-046A | |
Norad: N/A | |
Location: Precise location unknown or undisclosed. | |
Launch Date: 10 September 2011, 13:08:52 UT | |
Landing Date: 17 December 2012, 22:28:51 UT | |
Deployment: N/A | |
End Date: N/A | |
Function: Map lunar gravitational field. | |
Image Source: NASA |
Description
GRAIL’s twin spacecraft studied the internal structure and composition of the Moon in unprecedented detail for nine months and produced a detailed gravitational map of the Moon. They also pinpointed the locations of large, dense regions called mass concentrations, or mascons, which are characterized by strong gravitational pull.

Mascons lurk beneath the lunar surface and cannot be seen by normal optical cameras. GRAIL scientists found the mascons by combining the gravity data from GRAIL with sophisticated computer models of large asteroid impacts and known detail about the geologic evolution of the impact craters.
The mission also included MoonKAM (Moon Knowledge Acquired by Middle school students), a digital video imaging system that was part of the education and public outreach activities of GRAIL. Each MoonKAM consisted of a digital video controller and four camera heads, one pointed slightly forward, two pointed below and one pointed slightly backward. MoonKam was operated by undergraduate students at the University of California, San Diego, as well as Sally Ride Science, the foundation organized by America’s first woman astronaut, Sally K. Ride (1951–2012) to encourage young people to enter careers in science, technology, engineering and mathematics.
Read more:
https://solarsystem.nasa.gov/missions/grail/in-depth/