Here is the full list of all 100 Galactic Mining Corp achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
You upgraded 250 tiles
You completed 300 research squares
You upgraded 250 items
You upgraded 200 tiles
Increased your HQ size to Lv 12
You reached a corporation level of 30
You completed 30 crew contracts
You upgraded 200 items
You purchased 90 room upgrades
You completed 250 research squares
You upgraded 100 crew members
You upgraded 150 tiles
You drilled the core of 15 gas giants
Increased your HQ size to Lv 10
You drilled the core of 80 comets
You explored 1500 areas in a galaxy
You invested 20 times
You invested 25 times
You completed 200 research squares
You upgraded 150 items
You drilled the core of 50 moons
You completed 20 crew contracts
You reached a corporation level of 25
You drilled the core of 30 planets
You explored 1250 areas in a galaxy
You drilled the core of 70 comets
You drilled the core of 40 moons
You completed 50 Coretrium nodes
You drilled the core of 20 planets
You drilled the core of 60 comets
You completed 150 research squares
You drilled the core of 10 gas giants
You upgraded 60 crew members
You purchased 60 room upgrades
Increased your HQ size to Lv 8
You drilled the core of 30 moons
You drilled the core of 50 comets
You upgraded 100 tiles
You completed 10 crew contracts
You reached a corporation level of 20
You drilled the core of 10 planets
You drilled the core of 5 gas giants
You upgraded 100 items
You explored 1000 areas in a galaxy
Increased your HQ size to Lv 6
You drilled the core of 40 comets
You invested 15 times
You completed 100 research squares
You completed 30 Coretrium nodes
You explored 750 areas in a galaxy
You purchased 40 room upgrades
You drilled the core of 20 moons
You reached a corporation level of 15
You upgraded 30 crew members
You invested 10 times
You drilled the core of 30 comets
You upgraded 50 tiles
You explored 500 areas in a galaxy
You completed 20 Coretrium nodes
You completed 50 research squares
You drilled the core of 10 moons
You upgraded 50 items
You completed 5 crew contracts
Increased your HQ size to Lv 4
You reached a corporation level of 10
You drilled the core of 20 comets
You purchased 20 room upgrades
You explored 250 areas in a galaxy
You invested 5 times
You purchased 10 room upgrades
You upgraded 10 crew members
You reached a corporation level of 6
You upgraded 10 items
Increased your HQ size to Lv 2
You completed 10 Coretrium nodes
You explored 100 areas in a galaxy
You drilled the core of 10 comets
You upgraded 10 tiles
You purchased 5 room upgrades
You unlocked all the GMC systems
You reached a corporation level of 3
You completed 5 Coretrium nodes
You upgraded 3 crew members
You completed 1 research square
You completed 5 research squares
You upgraded 1 item
You upgraded 1 tile
You completed 1 crew contract
You explored 10 areas in a galaxy
You upgraded 300 tiles
You upgraded 360 tiles
You upgraded 300 items
You upgraded 360 items
You completed 80 Coretrium nodes
You completed 350 research squares
You completed 396 research squares
You upgraded 160 crew members
You upgraded 216 crew members
You completed 40 crew contracts
You completed 50 crew contracts