And I got this whole idea...well, the bit on the second side came first...and I got this idea about a fellow sitting in a cathedral waiting for this transport from space that was going to pick him up and take him on a trip. The guy is a bit blotto and starts thinking about A good friend of mine studies the stars, Venus and Mars are all right tonight.
This passage describes a scene of an individual waiting for a space transport in a cathedral while contemplating the stars, particularly Venus and Mars.  The character's state of intoxication adds to the surreal nature of the situation.