Not a TIFU at all. Your neighbors suffer from arrested development, and your parents' reaction wasn't particularly reasonable either. You're free to look at whatever you want with your binoculars and absolutely shouldn't take your neighbors complaints into consideration while watching the sky. Also, technically, (not that I recommend being a creepy asshole/paparazzo) as long as your neighbors do things in the open, or in front of windows, and you don't behave in a way that could be considered harassment or stalking, you're totally within your rights to just gawp at them all day long.