Very good innovative  game. At first I didn't understand the color table but then it clicked :D Relaxing fun game only when I didn't launched myself to infinity :D Had great experience.

And i find a bug probably:

There is planet hitbox in the corner.

Great work.

Finally found time to play your game. Interesting concept, but it took me solid 10 minutes to really understand how to play the game. After that it was quite easy to finish. It just took forever because the movement is a little to slow, as already mentioned by others. Also the aiming was a little problem because falling "off" is way too easy.

According to your game mechanics. I don't really understand the need of running around on the planet and clicking on the flower. It basically doesn't add any challenge to the game. It just makes the game longer for no reason and a little annoying.

Maybe add a little variety to your planets.

Some more sound effects would have also been nice, but there isn't much going on which could need sound.

But overall nice game idea. Would love to see what you could make out of this in the future ;)

(This is all a bit critical, but just to confirm I'm not writing this spitefully whatsoever.)

Gameplay wise it feels pretty tedious. Here's what I think may be causing that, and some possible solutions:

Movement speed is simply too slow. The walking speed around the planet could certainly use a big increase. The space speed could probably be doubled, and you could get away with even further speed increase on that by making the deflection off a planet even faster. 

The respawn system is a little confusing. If you fall off the map, then you are given a choice to respawn at the starting planet and keep all of your progress. Yet, the second you become brown you're forced to entirely restart. The only consequence for dying is having to do the puzzle all over again. Which greatly adds to the tediousness. The easiest solution for the problems in the death system is to simply not have one. Especially for puzzle games, for puzzle games death systems are by default unnecessary.

There is no way to keep track of your progress on unlocking the planets.  An indicator on the planet after you've unlocked it would help to keep track of that.

Onto other things:

I'm glad that there's a hotkey for the color pallet, it would be nice if there was a hotkey for the map and maybe even the controls as well. 

Art wise I would recommend making the colors on the planets less saturated, meaning instead of them being a raw 100% neon color, instead tone down the colors a little until it looks relaxing to look at. The dark purple planet already does this.

It's a pretty fine puzzle design. Perhaps the color mixing is a bit nonsensical, but other than that it's a legit working puzzle. 

The art for the player astronaut is pretty good.

While I think the respawn multiple choice system is a little confusing, I like the wording behind the accept fate option.

The music is pretty great, very great. It captures the atmosphere of a calm space puzzle well.

I'll be honest with you, after reading how to play I was still trying to find how to play. I spent 10 minutes on it and I couldn't manage to understand what my goal was. I think you should make more clear how to play maybe with some animation (tutorial) . When playing games usually the player wants to get to play as soon as possible and I think in this case is not possible. Your little dude is very cute! Sounds and music as well! 

The concept is really interesting and the main mechanic is very innovative but maybe you should find a way to make it less tedious, some animations would be cool too, the music is pretty cool