Unfortunately, the way back is not so easy and enjoyable. You have to watch out for columns of fire appearing from time to time. You can use them to fight Necromorphs, which die once hit by fire. Take the cargo elevator and ride it down. Go to the right. Wait until fire stops coming out of nozzles and continue your walk.
Walk past the regenerating Necromorph and climb down the ladder.
Upgrade Circuit 2/2 - Next to the door after climbing down the ladder.
Go through the door and move to another cargo elevator on the right - watch out for fire! Now you have to stay alive until the elevator comes.
When you get to the very top, call the gondola and ride it to the other side. Ride the cargo elevator down and turn left. Cross the door and the head through the room to the elevator on its end.
You'll find yourself in the room with two turret guns and gears blocked with explosives. When you destroy the first barrel, Necromorphs will appear. Keep eliminating them and destroying the barrels, until the huge explosion.
You'll be thrown into space. In order to end this chapter, fly straight ahead to the Terra Nova emergency entrance.
S.C.A.F. Artifacts 1/1 - Between huge ship debris on your way to the emergency entrance - it is best to notice them from the entrance side.