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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 on the eastern horizon.
The hill had multicolored bands perpendicular to the horizon.
At first, the hill was bright in the sday, but vanished in the snight.
But 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.
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   Eventually, the hill became a semicircle on the horizon.
% https://en.wikipedia.org/wiki/Semicircle
At stunrise, the semicircle was just a bright rim with a dark interior.
But the brightness grew downward from the rim to the horizon by snoon 
and then the whole semicircle was bright
and stayed that way till stunset.
But then the brightness shrank down from the rim
in the course of the snight and vanished at smidnight 
and there was nothing to see of the hill until stunrise came again.
And always the bright part of the hill had the multicolored bands always perpendicular to the horizon or
astronomically speaking always east-west relative to the sky.
It was all very puzzling.
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% sunrise to noon growing brightness 
% noon to sunset all bright 
% sunset to midnight shrinking brighte

   To add to the hill and other wonders, Zartlich encountered the
Splanet-Side islanders.  The first contact is its own story in 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 in cultural confrontation. 
The Splanet-Siders pointing said the hill was the Splanet---which was the first time 
Zartlich knew the name.
In pidgin as it eventually evolved, 
the Splanet-Siders said Splanet had always been there,
there was nothing strange, it was not ominous or terrifying, just part
of the natural order. 
% https://en.wiktionary.org/wiki/pidgin = "An amalgamation of two disparate languages, 
%    used by two populations having no common language ..."
% https://en.wiktionary.org/wiki/ominous 
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 from a low broad hill to a semicircle.   
% <p>

   Zartlich sailed farther east and the Splanet grew rounder and
then detached as a sphere from the horizon---it was not part of our Kearth at all.
The Splanet swaxed and swaned:  it had sphases.
First a bright rim on its top half, then swaxed to full, then swaned from the top down till
just a bright rim on its bottom half, then dark all over, then the cycle repeated.   
The cycle was as long as the 42-chour sday, but its start time of 
total darkness---the dark sphase---got closer to snoon as Zartlich 
went farther east and the Splanet got closer to Shenith.
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   And in its dark sphase, the Splanet 
it made a small second snight by covering the Stun for about 2 chours of 42-chour sday.
The Spars appeared.
On the islands, flowers closed, shpirds slept.
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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   But what was the Splanet.
It was vastly larger than the Spoons.
But unlike the spoons, it was always at the same place in the sky:
that is to say, from any fixed location on the Splanet-Side of the Kearth, the Splanet 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 >
Also there were new spoons on the Splanet-Side, not seen from Our-Side, and they
oscillated around the Splanet with periods shorter than a sday.
The new spoons transited the Splanet.
And spoons, new and old, went behind the Splanet and their
motions were correlated trickily with the darks spots moving on the
illuminated part of the Splanet.
One large dark spot was always opposite the Stun and traveled across full sphase.
% <! small variations are like the lunar libration >
% <p>

   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 sphases were now simpler to understand.
The dark sphase was total as snoon when the Splanet aligned with the Stun in the Eclopse
and the bright sphase was total at smidnight when the Stun was as shnadir.
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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---the dark spots---
and then blindingly clear that the Kearth itself orbits the Splanet. 
The Kearth, mighty and steady, was nothing but a spoon. 
% <p>

% <! 
% 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
% >