You made a great start on this game. Controls are tight, it looks nice and I love the use of shadows to telegraph where the asteroid will hit. By the way, do put the controls in the description, as it took me a bit of faffing to figure them out (I'm not familiar with PICO)
I just wish the game would have a goal. Add some collectibles across the map that spawn in random places, and you need to balance getting them with going for the pond to have a drink. Then slap a score that increases the longer you survive, with some kind of multiplier for how many collectibles you get.