The Traveler is the giant floating golf ball that we encountered on Mars. But Alpha Lupi is its consciousness. She is a being of the Void, like the Ahamkara. She has terraforming abilities that made our system habitable. Her body was crippled in the Collapse, yet her mind (Alpha Lupi) still communicates with us through our Ghosts and the Speaker (possibly)

:). Why do they fallen want her back so badly? Does she give them power or whats the deal? Thanks

The Traveler visited them some time before us, and gave them a Golden Age. But the Darkness found her, and the Fallen's prosperity fell away into a Whirlwind, what we would call a Collapse. The Fallen followed her, a Light in the expansive Dark, and arrived in our system in the wake of the Collapse. Our beef with the Fallen is pretty much just one big misunderstanding