Here is the full list of all 15 Constellations: Puzzles in the Sky achievements.
Complete Ursa Minor
Complete Lepus
Complete Lacerta
Complete Lupus
Complete Cygnus
Complete Leo
Complete Draco
Complete Ursa Major
Complete Scorpius
Complete Cetus
Complete Carina
Complete all worlds?
Complete 50 blackholes
Complete all worlds
Unlock Carina