Star Trails Over Kitt Peak

I have always wanted to try a star trails picture. A couple of weeks ago, I had an evening at Kitt Peak. The Moon was waxing gibbous and very bright and lit up the domes very nicely. I was with a group over by the 0.9 meter telescope so I set up my camera outside, programmed it to take 30 second exposures for a few hours, and went about my work.

I ended up with 162 pictures by the time we were getting ready to go. I made some adjustments in Lightroom to tame the bright sky and then imported them into a free program called StarStax. StarStax will add the individual images automatically and create the star trails picture for you. There are some options you can adjust, but it's pretty automated. Here is the result. 

Overall I am pretty pleased with the first attempt. I can spot a couple of flaws to clean up (and I would like to figure out where they came from, but I might have to look closely at 162 pictures to find the bloody things!) You can see the north star in its tight dance around the celestial pole and many other stars making nice trails. The lights of Tucsonare off to the right.

I have some old pics I used to make time lapses. I might go back and put together a few more of these from those old pics. 

Reprinted with permission from the Half-Astrophysicist Blog.