Here is the full list of all 47 Titan Attacks achievements.
Perfect Challenge Level 14
Destroyed 100 saucers
Used 25 smartbombs
Perfect Challenge Level 42
Perfect Challenge Level 35
Captured 100 live aliens
100 aliens escape capture
50 aliens escape capture
Everything maxed out
25 aliens escape capture
Completed the Titan levels
Perfect Challenge Level 98
Guns and addons maxed
Perfect Challenge Level 91
Killed 100 parachuting aliens
Upgraded addons to maximum rate
Perfect Challenge Level 77
Perfect Challenge Level 70
Captured 50 live aliens
Killed 50 parachuting aliens
Perfect Challenge Level 21
Perfect Challenge Level 7
Completed the Earth Levels
Completed the Moon levels
Completed the Mars levels
Completed the Saturn levels
Added all addons to ship
Perfect Challenge Level 49
Perfect Challenge Level 28
Perfect Challenge Level 84
10 aliens escape capture
Destroyed 50 saucers
Maxed gun power
Perfect Challenge Level 63
Maxed gun bullets
Perfect Challenge Level 56
Killed 25 parachuting aliens
Got the x9 multiplier
Got 100 skill shots
Captured 25 live aliens
Killed 10 parachuting aliens
Got 50 skill shots
Destroyed 25 saucers
Got 25 skill shots
Captured 10 live aliens
Got 10 skill shots
Destroyed 10 saucers