Atrox 881

Atrox 881 was a planet with conditions similar to that of Mars. It was located eight light years from Hereafter. With the Eleventh Doctor's help, Ixyldir and the Tanssor clan colonised the planet.

The Doctor returned the planet nine-thousand years later, where Ice Lord Azylax named him Belot'ssar. (PROSE: The Silent Stars Go By)