There is a lot of context before the Aurora crash, but I will only cover what you will encounter during the game, with short descriptions for understanding.
The Aurora, a category Alterra Long-Range Capital Ship, is comissioned to attempt a slingshot maneuver around Planet 4546B's atmosphere with 157 people on board and begin construction of a new phase gate in the Ariadne Arm. The Aurora is also tasked with locating the Degasi crew, though no one expected to find anything.
The Quarantine Enforncement Platform, an alien weapon system designed to contain the Kharaa Bacterium, detects the Aurora and fires at it, resulting in a crash, forcing the crew to evacuate.
Around 29-44 people manage to eject themselves in Lifepods 1-25, but only 10 Lifepods actually make it to the surface. Speculation can only conclude that other Lifepods could have made it to the surface, but succombed to the Ghost Leviathans that reside. Only one Lifepod carried a dead passenger. Each Lifepod crashed in a different area of the planet. Lifepod 5, in particular, housed Non-Essential Systems Maintenance Chief, Ryley Robinson. He is knocked unconscious for three hours by a loose panel during the Lifepod's descent to the surface of Planet 4546B.