The Moneans are a humanoid spacefaring race from the
Delta Quadrant. They were originally nomadic, they settled in an artificially
coherent planetoid of water.
The Moneans were mining oxygen from the planetoid. The
planetoid was losing cohesion in 2375.
Starfleet made first contact with the Moneans in 2375.
It was Lieutenant Tom Paris that had discovered an ancient reactor that had been
built by the original inhabitants.