Dyson sphere

A Dyson Sphere as referred to in the Freelancer Universe is what is scientifically referred to as a "Dyson Shell," a large structure fully encompassing a star and able to absorb 100% of its energy output. The only one of these spheres known in Sirius is in the Omicron Major system, and provided power to the Slomon K'Hara during the Nomad War of 800-801 A.S., at the end of which the sphere's power output was redirected into opening a Daam K'Vosh hypergate.

For more information, check out the Wikipedia article for Dyson Spheres here.