What is the biggest and smallest crater on the Moon?
The biggest crater is called Clavius and is 160 kilometers in diameter. On the backside of the Moon, there is the remains of an even bigger crater which is now filled-in and called Mare Orientale and is several thousand kilometers across. For the smallest crater, you will have to look at photographs taken by the Apollo astronauts. I seem to recall seeing dimples about a foot across or so in many of the pictures. The best telescopes can see craters about 1 kilometer across.
