Lunar Reconnaissance Orbiter Camera

 

Lunar Pits

Pits are remarkable features that provide a window into the subsurface. Their origin is somehow related to the volcanic plumbing system that transported lava that flooded the mare basins. The big question is – what do they lead into? An open cave system (in the form of lava tubes) or a dead end? An LROC image of the Mare Tranquillitatis pit taken when turning the spacecraft 45° showed that the floor extends at least 25 m under the surface (yellow arrows connect like features). But how far does the floor extend? 50 m, 100 m, 1000 m? What a great target for a robotic explorer – spelunking on the Moon!