I’ve seen a UFO too. I figure that mine was probably a weather balloon that was reflecting the sun. Did John Glenn ever figure out what it was that he saw on one of his flights?
When an astronomer sees a UFO, she refers to it as a possible scientific phenomenum and then after a while someone figures out what is going on. Sometimes they give it a name. It’s not that they don’t see unidentified things.
When an unidentified object is really close to the astronomer instead of a jillion miles from earth, it is known as a temporary malfunction of the telescope.