Here is the full list of all 17 Comit the Astrodian achievements.
Cleared Planet Tropika
Collect 100 Yellow Stars
Cleared Planet Magmo
Cleared Planet Wave
Cleared Planet Automata
Cleared Planet Stormside
Cleared Planet Frost
Cleared Planet Sunburst
Cleared Planet Sandpit
Cleared Planet Cloud
Cleared Starship Krater
Collect 500 Yellow Stars
Collect 1000 Yellow Stars
Collect 5 Red Stars
Collect 25 Red Stars
Collect 50 Red Stars
Destroy 100 Enemies