The Vorlon homeworld is hope to the Vorlon race and capital of the Vorlon Empire.
Next to nothing is actually known about the planet. After the Battle of Coriana VI, the First Ones left the galaxy beyond the The Rim, expeditions were sent to the Vorlon homeworld, of which none survived. Lyta Alexander has said that the Vorlon homeworld is "off limits" until the younger races are ready for the technology that is on the planet.
One million years after the end of the Second Shadow War, humanity, having evolved into beings similar to Vorlons, took residence on the Vorlon homeworld, renaming it "New Earth".