I don't neccesarily subscribe to any particular explanation concerning the possibility of aliens, but in general, I think there are enough strange happenings to at least study it. Moreso for me, for I've had several strange experiences myself. No, I wasn't abducted, but got shook to the core once when I sighted of an armada of merkabas. They were 'friendlies,' but didn't know that until they passed over. Geez, I hope nobody else is reading this. I'm not a UFO person and passed through my kooky state decades ago. Honest! :>
However . . . , a few years ago I was studying the artifacts on Mars and with a little creative photo shop, came up with something that is worth looking at. The face on Mars has been the topic of much research and discussion on all the old UFO and related publications, but it took a real stretch of the imagination to decide what the face originally looked like, or if it was, in fact, a face at all.
So I turned the picture upside down, cut it in half and mirror-imaged one side and pasted it together right down the centerline and came up with a startling likeness of a 'grey' with a little smudge work to removed the center line. Check this:
A calling card?