The Eunpwhas Cluster
The Halpheneans are a peaceful, fully aquatic, manatee analogue. Halphen itself is the only object in the system. It has a giant reactive mass in its center that radiates light and heat throughout the entire structure. There are giant crystalline structures floating throughout Helphen that have something to do with keeping the “planet” stable. The FWS are thought to have made Halphen, but it is not known why the did it. It seems to have some other purpose beyond just being a habitat for the Halphens.
Halphen has a lot of heavy water.