The Dysonsphere is a vast structure that completely surrounds a single star system and its planets. Because the Dysonsphere creates a closed environment, practically all of the energy radiated by its central star can be collected and utilized, making it one of the most powerful artifacts in the Zulu Sector.
Some of the planets in the Dysonsphere are habitable, and the Dysonsphere's impregnability make these worlds an ideal sanctuary from the dangers of the outside galaxy. For this reason, the Shedarians were evacuated to one of these planets when their homeworld, Shedar IV, was threatened by the Planetsmasher near the end of the Shyedarian Revolution. Although New Shedar became the new home of the Shedarian ruling council, since the end of the war, many Shedarians have chosen to return to Shedar IV.
Aside from their security, the other notable feature of the worlds within the Dysonsphere is that they exist in perpetual daylight, due to the reflection of the light from the central star off of the inner surfaces of the Dysonsphere.
It is also hypothesized that the existence of the Dysonspheres is somehow related to the current methods of propulsion in hyperspace.