I enjoyed the overall experience and liked the message behind the story. There were also a few moments that made me smile. One of the astronauts has an impressively strong core, sitting without a chair. Respect, Astro buddy.
I found myself getting a little lost a couple of times, so perhaps a bit more guidance could help players know where to head next. Some of the cutscenes also felt a little long for my taste, but I can see they were there to tell the story.
I had a couple of small bugs while playing. I slid off a block while talking to one of the astronauts, and after one cutscene I ended up falling to the bottom of the tower.
Overall, I had a good time playing. One feature I'd love to see is an option to return to the start after the end screen instead of restarting the game.