Great idea for a game, and nice and polished - The sound effects and music were beautifully ambient, clicky and perfect which matches the gameplay well, and I loved the pixel art.
One thought - it would be nice to have a little arrow indicator of which way you've gone off the scale (too high or too low) as I found myself losing the little marker off the end a couple of times on the last planets when switching between them.
Congrats on a fab game!