Here is the full list of all 31 Headlander trophies - there are 2 bronze, 26 silver, 2 gold and 1 platinum.
100% Headlander
Take Methuselah offline
Pop your head into every room to have a look-see
Defeat Methuselah Titan
Find all the mid-range zap locations
Dock with every body type
Find the entrance to Methuselah's Core
Find all alpha, beta, and gamma terminals
Find a power gem charging Shepherd and return to Rhea-6
Unlock all Upgrades
Find your body and witness Earl's sacrifice
Boost for 5.2155e-13 parsecs (10 miles)
Used Overcharge Boost to take out 25 enemies
Use Auto Sentries to take out 10 enemies
Drain all of the Energy S.A.C.s
Find all the bodies for Athena-7
Trigger all of the possible dance subroutines
Use the long range zap to Luna Citadel
Defeat the Kill Queen
Upload the Archive Data to Earl
Play a game of H.O.R.S.E.
Take out the Spectrum Shepherds
Shut down the power stations in the Power Dome to gain access to the Archives
Destroy 25 enemies using melee attacks
Execute 50 headshots
Align the Satellite Chalet dishes to gain access to the Archives
Find Frank the Dog and return him to Eudora-5
Thrust through the Pleasure Port to find the Satellite Chalet
Kill MAPPY without taking his map data
Escape the Starcophagus
Use explosions to kill 5 enemies