Here is the full list of all 19 Into the Void achievements.
Research any tech
Craft any item
Upgrade any item
Construct a new ship
Return home alive
Extract any resources from planet or star.
Complete act I.
Complete Act II.
Complete Act III.
Complete Act IV.
Complete a battle against an ultimate BOA fleet.
Complete a battle against an ultimate En Eire fleet.
Complete a battle against an ultimate Kalthem fleet.
Complete a battle against an ultimate Auslia fleet.
Fully research any branch
Complete a game on easy
Complete a game on normal difficulty
Complete a game on hard difficulty
Complete a game on extreme difficulty