Galaxian or solstellunarian is a non-binary gender from the galactian alignment system. It is a combination of solarian, stellarian, and lunarian. A galaxian person can be fluid between the three genders or can be all of them at the same time.
The galaxian flag was posted on Tumblr by user Temp-Nb-Blog on December 5 2016 along with the other combination flags.
The pink and brown stripes of the flag represent the varying levels in which people can experience being galaxian. The colors are a midpoint between those of the flags for the alignments being combined. The yellow stripe represent the non-binary nature of this gender. Black represents those with no gender. Grey represents the varying levels in which people can experience gender.