Here is the full list of all 20 Nyan Cat: Lost In Space achievements.
Jumped on Gold Platforms 1000 times
100 Cow items collected
42195 meters completed
5 times jumped over a doggy in a game
2000 bombs deactivated
20 enemies eliminated with Nyan Love
5 pills collected in a game
A UFO abduction survived 100 times
Tac Nayn touched 9 times
x250 score multiplier reached in a game
Played 10 times on Nyan Cat City theme
100 bombs deactivated
Stayed on the highest platforms at least for 30 seconds
Stayed on the lowest platforms at least for 30 seconds
Ran 1000 meters without touching any kind of enemies
Ran 25 seconds without collecting any food
A UFO abduction survived
Played with a skin other than NYAN CAT
Played in a world other than Space
250 enemies eliminated with Nyan Love