Pink Flyod. Did they know something we didn't?

I'm a big fan of Pink Flyod. I only became aware of their music about 10 years ago. Plenty of time to listen to a song and figure out the meanings. Recently I've noticed the amount of similarities and references to aliens.

For example:

Dark Side Of The Moon. The moon has a constant dark side, only the one side faces the earth at all times. Now subject to opinion, the dark side of the moon was said to have been explored by NASA. They didn't disclose much about their findings. Certain leaks on the internet explained how they had found a crashed space craft and an alien corpse. I'm not sure how true these speculations are, but it got me thinking. Why on earth would a rock band name a song and an album about the dark side of the moon. Are they trying to bring awareness to the subject?

Is There Anybody Out There? This basically explains itself. Are they asking the question whether aliens exist?

Album: The Wall
Track: "Is There Anybody Out There?"
Location: 0:43 - 1:07
There is also said to be hidden "noise". In the track "Is There Anybody Out There", a frightened Waters calls out "Is there anybody out there?!", in which a reply is immediately and noisily met by the aliens that have been living in their music for the last decade. Yes, Roger, there is somebody out there. Something has been monitoring you closely for years now. It features in almost every track Pink Flyod ever made, spanning from the 60's to the 90's.

There's tons of other examples, the list is too long to name them all. If you can think of any others, feel free to comment and add them.