There are a lot of great ways to do space or galaxy nails, but my favorite involves lots of layers and glitter.
I used a bunch of different polishes to varying degrees for this manicure. Here is the list: OPI Ink, OPI Yoga-ta Get This Blue, Sally Hansen HD Byte, Sally Hansen HD Laser, Chameleon Blue Sky, Chameleon Calypso, Wet n Wild Hannah Pinktana, Hard Candy Beetle, Love & Beauty holo glitter (no name,) and LA Colors Star Light.
All of the holographic glitter makes this manicure not the easiest to photograph, but I'm happy with how it turned out. I love catching glimpses of all the different duochromes and glitters in the sunlight.