According to a recent study on the current usage of programming languages in astronomy -http://arxiv.org/abs/1507.03989 http://arxiv.org/abs/1507.03989 - Fortra

According to a recent study on the current usage of programming languages in astronomy -http://arxiv.org/abs/1507.03989 http://arxiv.org/abs/1507.03989 - Fortran, quite popular in the old days, is still used by a quarter of scientists in the field. Python has been growing very fast in the last five years, eating away at the IDL share of astronomers.