
1) German surname
Found on
https://www.crosswordclues.com/clue/sommerfeld
[crater] This crater belongs to a class of lunar features sometines termed a walled plain – that is, it consists of a relatively flat interior surrounded by a ring mountain. The outer rim is only moderately eroded and it retains some traces of a terrace structure, albeit softened and rounded. Several small craterlets lie along the rim edg...
Found on
http://en.wikipedia.org/wiki/Sommerfeld_(crater)
No exact match found.