I just released most of the sprites I used in the game onto this site! I got as many of the sprites together as I could (some have been lost in the vortex of my computer, forever trapped in the game's source files) and uploaded them here.
Feel free to use them in any way that you like! If you do release a game using my sprites, please let me know (I'd love to check it out).
You can find the assets here: https://the-scientist-games.itch.io/space-sprite-set