Here is the full list of all 16 PLANET ALPHA trophies - there are 15 bronze and 1 gold.
Collecting the fourth artifact
Curiosity is key
Collecting the third artifact
Slipping through the cracks
Collecting the first artifact
How did they get it up there
Resting by the pond
Falling is not an option
Downwards is the new upwards
What lies beyond
Can't compete with the trees
Don't fight the flow
Another time another opportunity
Collecting the second artifact
Like a big family
It was never meant to happen