I had fun playing, this is an interesting take on the theme and I think you did a good job.
It looks like you have the skills to make the game a little more polished -- if you don't mind, here are some pointer that can go a long way:
- The game can have a rocket-flame animation on the spaceship by stacking a few sprite and shifting them around left and right.
- This is a personal preference, but I think the UI can look more polished if the text is smaller inside the buttons.
- The crashing animation can be a fun part of the game -- consider adding some sprites of an explosion and putting a longer delay before showing the game over screen
All in all, this was fun to play. Good luck, and I hope you keep it up!