
Halvmo~rk, that's what the first discovery team had called it. Twilight, the
twilight world. Its name in the catalogues was oflicially Beta Aurigae III,
the third planet out and the only one that was habitable of the six worlds
that circled the fiercely hot blue-and-white star. Or barely habitable. For
this planet was an anomaly, something very interesting to the astronomers who
had studied it and entered the facts into their records, and passed on. It was
the great axial tilt of the world that made it so fascinating to the
scientists, almost habitable to the people who lived there. - The axial tilt
of forty-one degrees and the long, flattened ellipse of the orbit created a
most singular situation. Earth had an axial tilt of only a few degrees, and
that was enough to cause the great change in the seasons. The axis is the line
about which a planet revolves; the axial tilt the degree that the axis
deviates from the vertical. Forty-one degrees is a very dramatic deviation,
and this, combined with the long ellipse of its orbit, produced some very
unusual results.
Winter and summer were each four Earth years long. For four long years there
was darkness at the winter pole, the planetary pole that faced away from the
sun. This ended, suddenly and drastically, when the planet turned the brief
curve at one end of the elliptical orbit and summer came to the winter pole.
The climatic differences were brutal and dramatic as the winter pole became
the summer one, to lie exposed to sun for four years, as it had done to the
winter darkness.
While in between the poles, from 40 degrees north to 40 degrees south, there
was endless burning summer. The temperature at the equator stayed above 200
degrees most of the time. At the winter pole the temperature remained in the
thirties and there was even an occasional frost. In the extremes of
temperature of this deadly planet there was only one place where men could
live comfortably. The twilight zone. The only habitable place on -Halvm6rk was
this zone around the winter pole. Here the temperature varied only slightly,
between 70 degrees and 80 degrees, and men could live and crops could grow.
Wonderful, mutated crops, enough to feed a half-dozen crowded planets.
Atomic-powered desalination plants supplied the water, turning the chemicals
from the rich sea into fertilizer. The terrestrial plants had no enemies,
because all the native life on the planet was based on copper compounds, not
carbon. Each flesh was poison to the other. Nor could the copper based plant
life compete for physical space with the faster growing, more energetic carbon
forms. They were squeezed out, eliminated-and the crops grew. Crops adapted to
the constant, muted, unending light, and unchanging temperature. They grew and
grew and grew.
For four years, until the summer came and the burning sun rose above the
horizon and made life impossible again. But when summer arrived at one
hemisphere, winter fell in the other and there was another habitable twilight
zone at the opposite pole. Then it would be possible to farm the other
hemisphere for four years, until the seasons changed again.
The planet was basically very productive once the water and the fertilizer
were supplied. The local plant life presented no problems. The Earth's economy
was such that getting settlers was no problem either. With the FTL drive,
transportation costs were reasonable. When the sums had been carefully done
and checked it was clear that food crops could be produced most reasonably,
and transported cheaply to the nearest inhabited worlds, while the entire
operation was designed to show a handsome profit as well. It could be done.
Even the gravity was very close to Earth norm, for while Halvmo~rk was larger
than Earth it was not nearly as dense. Everything was very possible. There
were even two large land masses around the poles that contained the needed
twilight zones. They could be farmed turn and turn about, for four years each.