You obtain this trophy by scanning all necessary species on 10 planets.
The list of fauna necessary is presented in the middle of the dashboard for each planet.
The species will be ticked up as you scan them.
A message will show in the bottom right corner of your screen when you scan a new species.
If this species was in the required list, the message will remind you how many are left to be scanned to get to 100 %.
There used to be an exploit whereby you could upload a 100% score on an empty planet.
This has been patched up, and the button does not show on the screen anymore.