1) I think you mean the Dawn 2) It went through the slipspace portal, but Medicant Bias diverted the Chief's half to Requiem. Otherwise, Infinity got to Requiem because of coordinates found at Halo .03, combined with Cortana's distress signal. ^^Requiem was just another military installation; the only thing that made it unique was the Didact was there. It didn't warrent the security of a Halo. While they likely did have access denial when it came to the Flood, they're all gone now. So there'd be less restrictions for average joes. Besides, Librarian [i] wanted[/i] Didact to be found, by humans at least, so they could learn from him and him from us. It's just that his hatred got so deep he ignored his Mantle. [Edited on 12.26.2012 3:06 PM PST]