Hi Jack! 
 JS> Using known physics as a guide line, Returning the information found
 JS> on earth to their home world, the aliens would be communicating to
 JS> relatives far into their own future. Whoever sent them on their cosmic
 JS> mission would have a wait of thousands of years for the results of
 JS> said mission. ...It almost seems pointless. 
What's the point of using "known physics"?  Surely what you refer to is a
human standard and has little to do with the possibility of alien races.
If we /have/ been visited by beings from another world, then it stands to
reason that they have capabilities far beyond our own and could quite
easily have developed "machines" (or other word of your choice) that are
outside our experience.  These machines may use a completely different form
of propulsion to anything we have even thought of.  Maybe they have harnessed
the power of tachyon particles and can therefore travel at speeds greater
than the speed of light and consequently can time travel.  Who knows?  The
only thing that we can be sure of is it is folly to think of their
technology in terms of human physics and abilities. 
 
 -=> Damian <=- 
... Don't believe in miracles. Rely on them.
~~~ Tag-O-Matic V.13b (Just 1 of 193281 Taglines) Stolen by Damian Steele
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