<br />Yes, I am pretty sure when you are talking astronomy and aerospace. I lived in Europe for a long time doing astronomy and had trouble learning it because all the astronomers spoke english. Yes, if you live there learning a local language helps, but not neccessarily from a job point of view. All professional astronomy conferences, no matter where they are, are in english. Almost all journals are in English. Of course I think it is great to learn another language but Ir eally don't think it will help that much in astronomy. If any, spanish because you may spend some time down in Cerro Tololo. In addition, at least for americans, you will have a tough time getting a job in Europe since the laws give preference to eropeans - and with few jobs it makes it hard.