Brian Goodrow (email@example.com) writes:
To further speculate on the "how the covenant found Earth" issue, I turn to the ever trusty Halo: Fall of Reach.
I believe that it might be possible that the small Covenant tracking device on the back of Keyes' old ship Iroquois could have sent the signal. After all, that ship was damaged extremely, and could have been sent back to shipyards on Earth for scrapping (or sent to Earth for another reason). It never says that that tracker was limited to only one data signal in the form of a crystal.
Tailed all the way back to Earth, just like a cheap detective story. Damn.