I'm going to be critical in this review, but it's with the best of intentions - note the rating I gave the game, it wasn't bad by any means, but I think it could have been stronger.
The main issue I had was with the narrative immersion. I was immediately pulled out of the story by how dysfunctional the characters seemed; NASA ensured that the sort of people allowed out in space were the sort of consummate military professionals who are able to get along with other people, and who don't manifest personality problems. The "Quest to Save Earth" wasn't necessary to the horror element - it wasn't really part of the stakes, only the survival of the protagonist was within the realm of possible action. It could have just as easily been occurring on a corporate freighter, where overly-sensitive human failures would have made sense.
Related to this is the principle of SHOW DON'T TELL; Badguy was simply labelled as >relevant term<, as opposed to behaving in such a way. It left me scratching my head - is this in his personality file? Or is this the character's conclusions? If it's the latter, having an inner dialogue would have been more effective.
Next, the environment. I noticed that the photo of the crew didn't include the protagonist - we should have had an image and job description.
And finally, a few gameplay critiques. First, the welding puzzle wasn't difficult or challenging, it just involved clicking; it should have been interesting, or removed. Second, the 3rd ending shouldn't have been an achievement - I wound up playing through two more times until I realized that it was simply the failure to reach the escape pod. It wasn't rewarding. A better reward would have been finding all of the possible dialogue. And third, well - this isn't so much a critique as a missed opportunity. Ultimately there's only one decision to be made during the game, despite a number of complex interactions. The engine and design seem ripe with the potential to have your actions affect the ending in subtle ways. The dialogue you choose on Day 2 doesn't seem to do anything, nor your accusation on Day 3. The long-term effects of choices are what create engagement; as things stand, everybody arrives at the end of the game in the same state, with a binary choice. The rest can just be fast-forwarded through.
Now that said, it was competently put together, the interface was intuitive, and it had atmosphere. Kudos on that, and I look forward to your future games!