Separating belief in ET life from belief in UFOs

Back in 1977, at the begining of the igneous petrography and petrology* class, the professor suddenly out of nowhere asked "How many here believe in UFO's?" Much to his amazement/annoyance/disappointment, quite a few students including myself raised their hands "yes".There was no further discussion, but my response was because I thought there were clearly flying objects I couldn't identify. I was in no way thinking space aliens.I still occasionally see this professor - I should ask him why he asked that question?Moose*looking at what makes up igneous rocks and learning how they came to be. The first "real" geology class after Introduction to Geology.