The video above shows of the work I've done on the star system viewer, as well as the surfaces of planets. It's best to watch it full-screen in 1080p, since Youtube compression isn't forgiving on pixel art. Almost everything you see is procedurally generated: the color of stars and planets, their surfaces, and atmospheric compositions. I've gotten environment generation down pretty well, here's the composition of 11 different worlds: lots of planet stats. One of the items on my to-do list is to beautifully, and intuitively, display these stats in-game. They'll come into play when you're trying to build a base on the surface. If there's no oxygen available in the air, but there's silicon-dioxide on the ground (sand), then you can build a converter to spit out raw silicon and oxygen! You could also make a greenhouse to convert the CO2 you produce back into breathable O2.
Other than regular programming and art, we're just getting ready for Habitat's Kickstarter in February (not far away now!). There'll be a cinematic trailer, being worked on by Ian Earle (whose don all the music so far), and lots of other goodies for those who donate!
If you have any questions, comments, or suggestions, just ask!