Titan was a moon of Saturn and was terraformed in the 21st century. Its climate was largely desert with windstorms.
Titan was the site of the Titan War and subsequently underwent scarring from the conflict.
When Gren confronted Vicious about his role in testifying against him, he was critically injured. He asked Spike Spiegel to get his ship going in the direction of Titan so he could die there.
Titan on Wikipedia