The term mons was firstly used for extraterrestrial mountains by Michael van Langren in 1645. He assigned names to some mountains on the Moon, but none of these names remain in use. Two years later Johannes Hevelius proposed the first names of extraterrestrial mountains still used. The lunar Alps and Apennines still bear names given by Hevelius, and five of his other mountain names nowadays refer to other features (in some cases his mountains later turned out to be bright rays from craters).