Here is the full list of all 55 Pixel Puzzles 2: Space achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Complete All Puzzles
25 Complete Puzzle
25 Puzzle Launch
4 Puzzle Launch
18 Puzzle Launch
21 Complete Puzzle
21 Puzzle Launch
16 Complete Puzzle
16 Puzzle Launch
Completet DL Launcher Puzzle
9 Complete Puzzle
9 Puzzle Launch
11 Complete Puzzle
11 Puzzle Launch
1 Complete Puzzle
1 Puzzle Launch
5 Complete Puzzle
5 Puzzle Launch
24 Complete Puzzle
24 Puzzle Launch
7 Complete Puzzle
7 Puzzle Launch
23 Complete Puzzle
23 Puzzle Launch
Launch Rotation Satelite
Launch Location Satelite
Launch Ghost Satelite
2 Complete Puzzle
12 Complete Puzzle
13 Complete Puzzle
22 Complete Puzzle
2 Puzzle Launch
12 Puzzle Launch
13 Puzzle Launch
22 Puzzle Launch
15 Complete Puzzle
15 Puzzle Launch
8 Complete Puzzle
8 Puzzle Launch
3 Complete Puzzle
3 Puzzle Launch
17 Complete Puzzle
17 Puzzle Launch
14 Complete Puzzle
14 Puzzle Launch
19 Complete Puzzle
19 Puzzle Launch
6 Complete Puzzle
6 Puzzle Launch
20 Complete Puzzle
20 Puzzle Launch
10 Complete Puzzle
10 Puzzle Launch
18 Complete Puzzle
4 Complete Puzzle