Nekron is the home world of the Nekross. Not much is known about it except that it created soldiers and also housed the lesser known Voolox.
Nekron is bigger than Earth in terms of size. Varg states this in the daughters of stone
"Earth is but a shrunken moon, Compared to the vastness of Nekron" - Varg
Nekron was mentioned to have seven moons, and it orbits two suns.