Here is the full list of all 36 Out There Somewhere achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Find 5 abandoned cores during one playthrough
Hit 100 mirrors with teleshots during one playthrough
Travel 500 screens
Find an ancient alien artifact
Have 5 or more teleshots on the screen at once
You have to wonder if they could make anything ELSE out of light. Hit 100 blue beams with teleshots during one playthrough
Spend 5 minutes in a room before going to a never-before visited one
Travel 250 screens
Finish the game
Travel through 75 unique screens during one playthrough
Get killed by lava, monsters, explosions, shots, and a moving platform, during one playthrough
Jump after being teleported 5 times in less than 8 seconds
Talk to all the aliens in the game in one playthrough
Kill 50 enemies
Travel 150 screens
Hit 100 green beams with teleshots during one playthrough
Travel through 50 unique screens during one playthrough
Travel 100 screens
Get an unsatisfactory compliment
Break 10 blocks during one playthrough
Hit 100 red beams with teleshots during one playthrough
Travel through 87 unique screens during one playthrough
Find 9 abandoned cores during one playthrough
Find all 11 abandoned cores during one playthrough
Kill 150 enemies
Kill every monster in the game at least once during one playthrough
Stand still for 60 seconds
Stay in the same room for over 8 minutes
Have 30 or more teleshots on the screen at once
Find all 3 ancient alien artifacts in one playthrough
Finish the game in less than an hour
Finish the game in less than 20 minutes
Defeat Grigori without using the teleport gun
Make it to the Alien City without touching any checkpoints
Find a way around the Treemen's Domain
Find the Gauss Gun upgrade