Baal
Baal is a radioactive wasteland of a Death World, famous for being the home of the Blood Angels, the most badass vampires in history.
The Blood Angels' Primarch, Sanguinius, fell upon Baal Secundus after he and his brother Primarchs were scattered across the galaxy by the machinations of the Chaos Gods.
Baal has two moons, called Baal Primus and Baal Secundus. Apparently, the moons were pretty damn close to some Paradise Worlds, but the Age of Strife slightly altered that. With nukes. The moons' populations now spend their time trying to evolve out of the Stone Age.
Or they did, until the mother of all clusterfucks ensued. Baal Secundus is still more or less intact thanks to the intervention of our Spiritual Liege (and when we say intact we mean "utterly trashed by the nids but extensively terraformed to go back to the days of the paradise moon of ancient times"). Baal Primus, on the other hand, is now completely bereft of life after Ka'Bandha showed up to flip off the Hive Mind.