The crater Petit (formerly Apollonius W) is located on the western rim of the mare.

This crater is white and surrounded by a well-defined ray system.

A small, bright-rayed crater located in northern Mare Spumans was known as landmark A-1/11 (1.7981° N, 65.0741° E).

Astronaut Michael Collins tracked this landmark on revolution 4 of Apollo 11.

[2] Collins referred to this crater as KAMP, after his three children and wife (Kate, Ann, Michael, and Patricia).