What is "littrow"

Littrow is a lunar crater named for astronomer Joseph Johann von Littrow. It can also refer to:

Littrow is a lunar crater that is located in the northeastern part of the Moon's near side, on the east edge of Mare Serenitatis. Some distance to the northeast is the prominent crater Römer, while to the south is Vitruvius.

The rim of Littrow is heavily worn and eroded, especially along the southern wall. The interior has been flooded with lava in the past, leaving a relatively smooth, featureless surface with no central rise.