Geological Chronicle
Paschen is a lunar impact crater spanning 127.36 kilometers on the far side of the Moon. Situated east of the walled plain Galois and southwest of the huge Hertzsprung, the feature is named for German physicist Friedrich Paschen.
The crater's southern rim has been substantially degraded by overlapping impacts. The relatively large satellite crater Paschen M partly overlies the southern rim, nearly forming a merged pair separated only by a section of irregular terrain along their common border, while the smaller crater Paschen S lies across the southwestern rim.
The remainder of the rim is worn and eroded by subsequent impacts and deposits of ejecta, forming a rounded dip into the interior. A small chain of craters cuts across the rim and inner wall to the west-northwest, and several small craterlets mark the southeastern floor.