English: Lunar rock sample collected during Apollo 15 mission in late July-early August 1971 by Astronauts David Scott and James Irwin. Weighing nearly half a pound, this basaltic rock is believed to be 3.3 billion years old. It is housed in a protective case in an atmosphere of pressurized Nitrogen. Photo was taken at The Lyndon Baines Johnson presidential library and museum in Austin, Texas.