Here is the full list of all 23 Helium Rain achievements.
Unlock a technology
Unlock every technology in the game
Dock at a station using manual controls
Travel with a heavy ship to a sector with enemy forces twice as strong
Capture a ship
Destroy a meteorite
Don't be the lowest-ranked company
Be the highest-ranked company
Complete the Pendulum quest chain
Destroy a ship by colliding into it
Destroy an enemy freighter
Destroy an enemy fighter
Destroy an enemy heavy military ship
Destroy an enemy fighter with a turret in manual control
Complete a resource trade
Build a space station
Build a ship
Own all ships in the game
Win a battle
Attack a company you were not at war with
Evade an incoming missile
Hit a heavy ship with an unguided bomb
Hit a light ship with an unguided bomb