The Reapers took Earth in a matter of hours. The Alliance knew the first wave would arrive from batarian space, but they were unprepared for the speed and scale of the attack. The Reapers bypassed the Sixth and Seventh Fleets at Terra Nova and Eden Prime, flying straight from relay to relay where they could neither be tracked nor intercepted. The tactic was unexpected, since the navies of organic species would never risk coming out of FTL within combat range or leaving enemies at their backs to threaten supply lines.