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