Orange erratic light over Tucson

I was walking to the store and happened to look above me and noticed a strange orange colored light floating in a west to east orientation parallel to the Catalina Mountains. The light was flickering erratically and was making no noise. I noticed that another aircraft was above it at the time and was flying north. The object was behaving differently from the normal aircraft you see at night. It was not flashing red to white in rhythm, it was flashing orange to white randomly vanishing in out in brightness. Also, the movement was slow and erratic as well. When it got close to the Rincon mountains, it completely vanished. The observer has never before seen or witnessed any UFO activity, but is a frequent star gazer.