In order to keep Chaos from taking over the universe, SailorGalaxia, Senshi and guardian of the Galaxy, strongest in both heart and will, battled with Chaos. But Chaos, like evil, can not be destroyed. So Galaxia took Chaos with in herself.
But it was too much, and the only way to keep Chaos from taking over her entire being was for Galaxia to release her StarSeed into the futherest corners of space. This way, Chaos would not be able to take control of Galaxia’s power to dominate the universe.
But still, Chaos took over Galaxia’s body and mind.

Sailor Senshi of this Solar System fought Galaxia. But in the end, all of them fell, the Inners and Outers, all destroyed, with barley more then a glance.

All that remained were SailorMoon, ChibiChibi, and the StarLights.
Galaxia took SailorMoon's StarSeed. ChibiChibi then came to SailorMoon, and gave SailorMoon her StarSeed.
As ChibiChibi gave SailorMoon her StarSeed, ChibiChibi then transformed in to a sword. ChibiChibi told SailorMoon that Chaos had to be destroyed, and could be stoped with this sword. And with in SailorMoon, ChibiChibi, the Light of Hope, the StarSeed of SailorGalaxia, knew that she has found the Senshi who would embrace her warm light and battle against Choas.

However SailorMoon refused to fight, even as Choas attacked, shattering the sword.
But through all of the attacks, SailorMoon could only see that Galaxia had once been a SailorSenshi, that once she had been good. She tried to show her that there was no reason to try to control the Galaxy, that it was bad to do this. She told Galaxia that this wasn't what she wanted.
SailorMoon reached out, and found Galaxia within Chaos.

SailorMoon scattered Chaos, placing a small amount in to the hearts of everyone in the universe. This was the only way, as Chaos could not be destroyed. Placing a little into every one, the good will outweigh the evil. For the Light of Hope is within everyone as well.

And so it will remain, with the strength of the Sailor Senshi guarding the universe, protecting the pureness within each of us.

Here is a nice video clip of galaxia. (.ram file, zipped) galixia.zip

A really great site for info on Galaxia is GOLDEN LIGHT

The information found on this page was obtained from VKLL's Fansubed version of SailorMoon Stars.