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.
Kill 150 enemies
Find all 3 ancient alien artifacts in one playthrough
Find the Gauss Gun upgrade
Finish the game in less than an hour
Finish the game in less than 20 minutes
Defeat Grigori without using the teleport gun
Have 30 or more teleshots on the screen at once
Hit 100 mirrors with teleshots during one playthrough
Have 5 or more teleshots on the screen at once
Find a way around the Treemen's Domain
Make it to the Alien City without touching any checkpoints
Travel 500 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
Travel 250 screens
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
Find 5 abandoned cores during one playthrough
Travel through 50 unique screens during one playthrough
Hit 100 red beams with teleshots during one playthrough
Hit 100 green beams with teleshots during one playthrough
Travel 150 screens
Stand still for 60 seconds
You have to wonder if they could make anything ELSE out of light. Hit 100 blue beams with teleshots during one playthrough
Travel 100 screens
Spend 5 minutes in a room before going to a never-before visited one
Get an unsatisfactory compliment
Find an ancient alien artifact
Break 10 blocks 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 every monster in the game at least once during one playthrough
Stay in the same room for over 8 minutes