The first fifteen are based on the words. The last five are based on five of the icons in the inspiration post.
I started counting from below the cut of the inspiration post. You may need to add three to match them up to the originals. It should be obvious when you've got it right.
Alternates and a couple extras I rejected for not being "space" themed -- don't consider these for the icontest:
Rules for use: Credit and comments are optional (though appreciated), just don't take credit for them. Don't repost except for by using them yourself. Don't hotlink. Don't edit. (I still have the .xcfs and can probably change things for you if asked.)
Resource credits. In addition to my normal texture collection listed there, I used the contest's inspiration textures by luminousdaze (cloudy mind, in starlit, open, and separation) and whitebamboo (galactica, in up and the one based on inspiration icon 15). So if it matters, I didn't ignore that part of the inspiration post.
Almost all caps were from Sonic Biro.