The Monitor's Satellite was the space station from the original Monitor, capable of watching over the whole multiverse. During the Crisis of Infinite Earths and the death of the Monitor, the satellite served as an operational base for Harbinger, Pariah and Alex Luthor to recruit all heroes and villains from the pre-Crisis Earth-1 and Earth-2 to prevent the collapse of the multiverse. But just before a team of volunteers were dispatch to save Earths S, X and 4, the satellite was attacked by the Anti-Monitor and apparently destroyed.
The satellite would reappear severely damaged but still operational in Multiversity, as the last monitor's Nix Uotan base of operations. It would be to this satellite where the heroes of at least 50 parallel universes would be summoned by Thunderer to stop the attack of the Gentry. Currently it serves as base of operations for Justice Incarnate.