Here is the full list of all 37 Rebel Galaxy achievements. It takes around 50-60 hours to unlock all of the achievements on Windows.
Destroy 2,500 Fighter-Class Craft
Kill 20 Pirate Lords
Mine 50 asteroids using a Fault Tracker
Break 10 blockades
Shoot down 500 torpedoes
Destroy 1,000 Capital-Class Craft
Find an Antimatter Speck
Become neutral to pirate factions
Pirate a merchant
Reach a Net Worth of 50 Million Credits
Complete the main campaign
Find the Face of Gozu
Purchase a Dreadnaught-class ship
Collect 100 bounties
Purchase a Destroyer-class ship
Hack 10 transponders successfully
Reach a Net Worth of 5 Million Credits
Complete 50 missions from the mission board
Rescue 20 merchants
Join the Mercenaries' Guild
Gather 200 objects with a tractor beam
Kill 1 Pirate Lord
Jump out of the first solar system
Salvage 50 Containers
Successfully bribe a Militia official
Reach rank 5 in any Guild
Become friendly to the Militia
Find a Progenitor Shard
Break 1 blockade
Destroy 250 Fighter-Class Craft
Destroy 100 Capital-Class Craft
Trade with a Merchant while in flight
Collect 10 bounties
Purchase a new ship
Hire a mercenary
Join the Merchant's Guild
Woke Trell