Here is the full list of all 7 Antigravity Racing trophies - there are 2 bronze, 3 silver and 2 gold.
Get on each track a one star rating
Get on each track a two stars rating
Get on each track a three stars rating
Collect enough coins and buy a new racecraft
Upgrade your racecraft on any aspect
Fully Upgrade one racecraft of your choice
Collect enough coins and buy all racecrafts