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% poem140_amazing_stories.tex
\centerline{Amazing Stories:  Zartlich Twelver}
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\hafskip
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   Zartlich Twelver---so called because of the extra two tentacles---was a voyager in all respects. 
On the Kearth Ocean and in imagination.
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   When he---and his trusty crew---sailing east first reached nearly the edge of what we now call 
the Splanet-Side, they first saw what seemed a broad, low, distant hill, very dark at stunrise, 
very bright at stunset---the brightness grew in the course of a sday from the ridge of the
hill in multicolored vertical bands vertically downward to the Ocean horizon. 
As Zartlich sailed farther eastward on the Splanet-Side, sday by sday, the hill grew 
taller and spread broader---but it rounded incredibly like no hill or mountain---and 
clearly immense, it seemed to get larger, but not closer.
There was also a complex evolution both in a sday and with farther travel east of the
dark sphase and bright-band sphase of the hill, always with the sphases divided by an arc.
And on bright-band sphase, there were dark spots always appearing at the lower edge
and moving to the ridge of the hill where they vanished.
Some moved quickly took less than a sday;  some moved slowly and took many sdays.
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    Then there were the Splanet-Side islanders. Zartlich's contact with them is 
its own story of cultural confrontation. There was no trace of common spoken language 
and the explorers and Splanet-Siders communicated insofar as that is possible 
by simple mating---which is its own story of cultural confrontation. The Splanet-Siders 
said the Splanet---the first name for the hill that Zartlich heard---had always been there, 
there was nothing strange, it was not ominous or terrifying, just part 
of the natural order. There were myths of heroes going to the Splanet and having adventures there. 
All romances, no world-as-it-is reports. But these Splanet-Siders were bound to 
their own islands and nearest neighboring islands. They had spread over the islands 
over generations with limited communication to distant islands. They had never seen the Splanet grow.
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   Zartlich sailed farther---the Splanet became a hemisphere, standing $10^{\circ}$ above 
the eastern horizon, then a standing more-than hemisphere, then separated altogether, 
a sphere in the sky above, not a part of our Kearth at all.
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   The Splanet was an astronomical body, vastly larger than the spoons and unmoving if you 
were unmoved:  that is to say, from any fixed location on the Splanet-Side of the Kearth, it always had
a fixed position relative to the ground aside from small variations due 
to the small eccentricity of we know what.
% <! small variations are like the lunar libration >
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   Once the Splanet was in the sky,
it made a small second night by covering the Stun for about 2 chours of 42-chour sday.
Flowers closed, shpirds slept, the Spars appeared, 
it had always been thus. The Farther Splanet-Siders saw nothing remarkable 
in this---it had always been thus. It was just the Eclopse.
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   Farther and farther, Zartlich sailed until he reached Sub-Splanet Island 
which had never been reached by the Splanet-Siders.  There the Splanet stands always 
at Shenith and the Eclopse straddles Snoon.
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    The dark and bright-band sphases were now simpler to understand.
The dark sphase was total when the Splanet aligned with the Stun in the Eclopse
and the bright-band sphase was total at Smidnight when the Stun was as Snadir.
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    All along in his voyage, Zartlich was also discovering new spoons that never rise 
above the horizon on our side of the Kearth and which transit the Splanet.
And spoons, new and old, were correlated trickily with the darks spots moving on the
bright-band sphase of the Splanet.
One large dark spot was always opposite the Stun and traveled across bright-band sphase
over the Smidnight chour. 
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    From his observations, it became clear to Zartlich that the new spoons orbited the Splanet, 
and then clear that so did the old spoons and that they both cast shadows on the Splanet, 
and then blindingly clear that 
the Kearth itself orbits the Splanet. 
The Kearth, mighty and steady, was nothing but a spoon. 
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% <! 
% The Splanet is Jupiter (Radius =71,492 km), the Kearth is Io. 
% But Jupiter is at the Earth's distance from the Stun 
% Io day 1.769 days = 42 hours, orbital velocity = 17.334 km/s
% R_orb = 421,700 km, theta_rad = 72/420 = 0.17*60 = 10 deg,  theta_diam = 20 deg.
% eclipse = 140,000/17 = 0.8*10**4 s = 8000 s = 2.2 hours
% >
