How did those characters flee so far in the Mass Effect 3 ending?

Question

Obvious spoilers:

No matter the end you get, you see Joker and the Normandy's crew escaping the explosion caused by the Crucible. He later crashes on a jungle planet and, under some circumstances, you could see him getting out from the Normandy along with some of your squad members. The sky they see after crashing seems to indicate they landed on the moon of a Jupiter sized planet.

Correct me if I'm wrong, but this planet should be outside of Sol's system and they cannot reach a system with a habitable planet within a matter days, or hours in the best case scenario. Thus this means the Normandy used the Charon Mass Relay before it exploded.

How did Joker and the surviving Normandy crew members end up that far from Earth, the battle, and Shepard?

Answer 1

Spoily spoil spoil

The size may be something of a red herring - after all, the moon observed by the stargazer in the epilogue seems pretty huge - assuming that took place on Earth. However, the shock wave caused by the crucible was being transmitted by the Mass Relays (destroying them in the process). It's possible that the Normandy got caught in the wave and shunted through Earth's Mass Effect relay meaning they could have ended up anywhere in the universe.

Also spoiltastic

It is worth noting that in the extended cut of Mass Effect 3, Joker has to be persuaded to leave Shepard by (in my playthrough) Ashley.