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