The USS THUNDERCHILD is in that universe.  'Why' doesn't matter anymore.  It's been there two years already.  By now, 'Why not?' seems as valid a question as 'why?'.

Ninety years ago, the ship left this Earth searching for a way home back to its own universe.  

One temporal wave later, the ship slips ninety years ahead in time, still in this universe.  No way home in sight.

A return to this Earth seems the only reasonable course. 

If they are still welcome...

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