Great Scott (lunar sample)

Lunar Sample 15555, better known as "Great Scott", is a large Moon rock discovered and collected on the Apollo 15 mission in 1971. 

 The sample 
Apollo 15 mission commander David Scott collected Lunar Sample 15555 in the Hadley-Apennine region of the Moon, on the edge of a Moon valley called Hadley Rille at Station 9A. The large sample was soon nicknamed "Great Scott", because of how big it is and the name of the astronaut who discovered it.

The rock is a type of volcanic rock known as basalt and is rich in a green mineral called olivine. It weighs about 9.6 kilograms (21.2 pounds), making it the largest sample brought to Earth from the Apollo 15 mission, and the one that has been studied the most.  

The term Great Scott started to be used for the sample as soon as the next mission, Apollo 16, because Charlie Duke used the term just before picking up another Moon sample nicknamed Big Muley. Big Muley is the largest rock (11.7 kg) brought from the Moon; it's the only Moon rock bigger than Great Scott.

 Display 
Great Scott is currently stored at the Lunar Sample Laboratory Facility at the Lyndon B. Johnson Space Center, the main facility where NASA trains astronauts and directs missions.  

Pieces of it are on display at the National Museum of Natural History in Washington, D.C., the Tellus Science Museum in the state of Georgia, the Madrid Deep Space Communications Complex in Spain, the LROC Lunar Exploration Museum at Arizona State University, and the Science Museum in London, England.

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