This is the Green Series of planet coloring tools.
The Sky Greeninator colors the sky Green.
The Green Terra-Coloring colors the land Green.
The Sea of Green colors the water Green.
Three of them (Skies of Red, Purple Terra-Coloring, and Deep Blue Sea) will be given to you automatically if you choose the "I want to paint planets" mission from your homeworld.
The rest are found the same way as artifacts: by visiting a planet with yellow radar waves coming out of it, using the radar to locate the item, and then using your Abduction Beam to acquire it. They have the same appearance as terrasculpting tools, so you can't be sure what you will get.