(disclaimer: AIM judge review here! these are just my opinions and thoughts, you can take from them whatever you like! music is subjective and all that. <3)
i like the blippy aux percussion noises and background textures, which feel like the most 'spacey' thing in the tune as far as thinking about the artwork goes. overall, the tune feels immediate, close-to-home, warm and friendly, which are not things i'd immediately associate with a vista of stars and planets, though of course it's pleasing to listen to. maybe some bigger, longer pad sounds and some drumless (or even tempoless) segments could broaden the sense of space here. something you have down nicely is reworking a melodic motif as a sequence to be used again with different pitches or to be taken in a different direction. though they could stand to repeat a little less, i sense life in your melodies.
i'd love to hear some extra detail in the supporting parts, especially the harmonies; both giving them more of a direction/arc (vs sorta wandering up and down around the same space) and more rhythmic detail. a lot of this song is very "on the downbeat, every downbeat"; some more push and pull would be great, especially over the course of five minutes. the texture could vary (short vs held notes, for one thing), the speed and rhythm could both vary (parts of the phrase where you wait longer to change chords or accelerate the speed to build tension), and for that matter, building into some denser, more dissonant harmonies and then resolving them could also give phrases more of a satisfying overall path (vs as it stands, it feels like most of the chords used carry the same weight). as it stands, this song sits at around the same energy level the whole time, and because there's not a lot of introduced rhythmic or harmonic tension, it can only ultimately feel a bit static and unfocused. that's where i could see some room for improvement here!