Ionov is a hive world with a populatoin of approximately 50,000,000,000 (50 billion). The presence of such a world is a boon to the Tempest Angels due to the astronomical size of industry and number of recruits for the Imperial Guard, further adding to the security of the area. The entire planet is covered in one never-ending city. It is under the governance and protection of the Tempest Angels.
It has a Planetary Defense Force of 86 million.
When the sector is under direct attack, the Tempest Angels take command and fight alongside the Imperial Guard of Ionov, as such, they have formed a close friendship surprising for an Astartes Chapter and mere humans.