Mount Marilyn is a lunar mountain within the Montes Secchi, which separate Mare Fecunditatis to the east from Mare Tranquillitatis to the west. It was named at about the time of the Apollo 8 mission to the Moon in 1968 by astronaut Jim Lovell for his wife, Marilyn. The name was informal until July 26, 2017, when it was officially recognized by the IAU.[1] Its approximate position is 40 degrees E, 1.1 degrees N.[1]
The small crater that has impacted the north tip of Mount Marilyn is known as Secchi O crater. The small crater unofficially known as Weatherford (probably because Apollo 10 Commander Tom Stafford is from Weatherford, Oklahoma) is located just west of the north tip.