One thing I love about Pittsburgh is all the parks, and I'm making it my mission to visit all of them. One I hadn't been to before was Deer Lakes, and when I heard the Wagman Observatory was having a "star party," I thought that would be a perfect excuse to experiment with long exposures.
There is a whole field of "star photography," involving cameras connected to telescopes and tracking devices. But I'm too lazy for all that :-) My pictures were (mostly) of things much closer -- in fact, attached to -- the Earth.
All the lights there are red (to preserve night vision), and they have two large telescopes, one an historic 11-in reflector built in 1908. Here I am looking into the visitor's area -- and sometimes at the camera.
Here I'm checking on the rotation of the Earth (yup; still turning). And experimenting with adding white light (with a small pen flashlight), to see how it affects colors. Apparently the more light I add, the more "true color" the picture becomes.
Everyone was busy assembling gear and retrieving items through the night. I almost lost my backpack in the dark a couple times. Note to self: next time get a red filter for my flashlight!
If you try to hand-hold the camera, the crescent moon starts to look like the Challenger disaster :-)
Anyway, had a great time checking out distant comets and even more distant galaxies. Jupiter and Venus were out as well. I love this "ghost effect" of long exposures. Somehow on this one I got both the very faint red light leaking through the door below, blue in the sky (even though it was actually very dark), and somehow even clouds. I was exposing for 30s at ISO 1000 or so, F11-22.