Very nice work and shots Nate, way out of my league and I would love to have a try at this sort of thing. Love the effects you got and the lighting in magic in these.
Having a camera that handles high ISO paired with a fast super wide lens helps a lot. It's been a bunch of trial and error for me with astro-photography.
Some tips I've used:
1. manually set the focus to infinity
2. Use Highest ISO setting + fast shutter speed (5-10 sec) to frame shot. I still struggle doing this at times
3. lower ISO and shutter speed for better image quality
4. post proces
I'm still learning and need improvement. One of the things I struggle the most with is staying awake. I start taking photos then get too tired to perfect the shot.