Airplanes at night

Sometimes I go out at night and take photos of stars. With a telephoto lens, you can photograph the Orion nebula, Andromeda, and a few other things. I'd like to eventually hook my camera up to a stronger telescope though, and maybe use an equatorial mount to take long exposures without the stars blurring.

These photos are of airplanes, however. If you take an exposure several seconds long, you can get interesting patterns caused by flashing lights on the planes.