Why the Nomads really destroyed Earth

[Lythrilux]

The cutscene occurs right after the ships have left. It doesn't create an error in the time continuity, as the settlers survive the attack as they are not there when it occurs. The theory doesn't imply another dimension, the Nomads simply move through time and space - not universes. In regards to where they go next, no one really knows the answer to that. They'd probably begin construction of something to beam themselves back to Sirius.

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