Obviously we see many variations of aliens in movies, but I'm curious as to why and when they were seen to be green and look largely human-aside from having a huge head (in popular culture).
hi! FYI, there's a section in the FAQ* on aliens. I've given it a scan and there are no mentions of "green" creatures, but you may be interested in taking a look through the threads since they discuss the general topic of the emergence of the concept of aliens
Early ideas about aliens and UFOs
*see the link on the sidebar or the wiki tab