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C00002 00002	INTERSTELLAR VOYAGE PLOT
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INTERSTELLAR VOYAGE PLOT

	A multi-generation 800 year journey is launched to a nearby star
in the year 2300.  Fission power is used to expel reaction mass.  In order
to keep a more viable society, advantage is taken of the fact that space
voyages are like pyramids.  Mass at the beginning doesn't cost much whereas
mass at the end is extremely expensive.  Therefore, until the last stages
of deceleration, it is planned to have a larger colony than will land at
the star.  The population reduction will be carried out by birth control
starting 150 years before the arrival time.

	All goes well for about 400 years, and the ship stays in touch
with advances in Earth science and culture, because electronics permits
continuous receipt of radio and TV.

	Over a few years the radio and TV fare received seems to have
become restricted, and then it becomes more natural again, but the
curiosity of a pertinacious social scientist has been aroused.  He
looks at the period of constraint without finding much, and then he
finally thinks of looking at the period immediately before the constraint.
One thing he notices is scientific speculation about a proposal for
lengthening human life.  Like many scientific speculations this one
seemed from the broadcasts to have petered out and then to have
been decisively refuted.

	However, his suspicions are aroused, and he speculates:  What
if they discovered a way to lengthen human life?  What if we could
use it too?  This would put a terrible social stress on our ship crew,
because we have to  reduce our population in the deceleration stage,
and we were counting on it happening naturally.

	He ascribes the constrained transmissions to a need by Mission
Control to hide the longevity discovery from the space ship crew.
The increased naturalness came from their getting better at their
task of presenting a fictitious society.  However, since longevity
would have an immense effect on society, the society they are showing
in their radio and TV transmissions
must differ increasingly from the real society.  In particular, the
fictitious society can't advance as rapidly as the real society, since
many of the real advances are related to the longevity and take it into
account, and not much manpower can be devoted to inventing advances
for transmission to the ship (ships?).

	He thinks he detects evidence of fictitiousness.  In particular,
he thinks that certain entertainers of today can be closely identified
with entertainers of a century earlier.  However, his colleagues are
doubtful, and he despairs of getting conclusive evidence, and he isn't
sure he isn't making it all up.

	Finally he gets his evidence.  One possibility is that he
hypothesizes and finds a concealment cipher in the transmissions
giving the true facts.  It was sent, because Mission Control
couldn't be sure that their fake broadcasts would succeed in
fooling all the ships, and wanted to tell the truth to those who
were suspicious enough to look for it.

	Better perhaps is the explanation that the speculations about
how to achieve longevity that were broadcast just before the censorship
period were close enough so that the scientists on the ship were able
to discover what remained and make the longevity work as soon as they
suspected that the result was being concealed.  Another possibility is
that they discover it independently.

	Having discovered the truth, they agonize about whether
to kill enough of themselves to carry out the plan.  The alternative
turns out to be to reduce the mass flow while increasing the velocity
of expulsion.  This reduces the deceleration but makes the fuel last
longer.  At the cost of missing the target star and prolonging the
voyage to 4,000 years, they can avoid reducing their population.
They must also take a chance on a star with less prior knowledge.

	They decide to inform Mission Control of their discovery
and wait 20 years for a reply.