Aether Mission is a reskin of the Atari Flashback version of Planet Smashers. It's also one of many space-themed Nice Code games with "Aether" in the title.
As with many Nice Code games, pressing Up, Down, Left, Right, holding A + B (pressing A before B) and pressing Right on the title screen will briefly display a credits screen. Nature Color Game is one of several aliases used by Nice Code, and PJ most likely refers to the Power Joy series of Famiclones which many Nice Code games were released on. Uniquely, the ASCII art in this game is rendered out of A's instead of 0's.