But I was interested in the tropical plants they grew in “Oahu”—I had never seen a lot of them before. I noticed that most of the plants were marked “M-G” while a few were tagged “N. T.” I asked one of the gardeners; he said that “M-G” meant “mutation-Ganymede” and the other meant “normal terrestrial.”
I found out later that almost everything grown on Ganymede was a special mutation adapted to Ganymede conditions.
Beyond there was another of the big multiple sheds named “Texas”; it had real cows in it and was very interesting. Did you know a cow moves its lower jaw from side to side? And no matter what you’ve heard, there is not one teat that is especially for cream.
I hated to leave, but “Texas” shed smelled too much like a space ship. It was only a short dash through the snow to the Exchange where all of Leda’s retail buying and selling takes place—big and little shops all under one roof.
I looked around, thinking I might take a present back to Peggy, seeing that she was sick. I got the shock of my life. The prices!
If I had had to buy in the Exchange the measly fifty-eight pounds of stuff they had let me bring with me, it would have cost—I’m telling the truth!—several thousand credits. Everything that was imported from Earth cost that kind of money. A tube of beard cream was two hundred and eighty credits.
There were items for sale made on Ganymede, hand work mostly, and they were expensive, too, though not nearly as expensive as the stuff brought up from Earth.
I crept out of that place in a hurry. As nearly as I could figure the only thing cheap on Ganymede was food.
The driver of the commissary tractor wanted to know where I had been when there was loading to do? “I should have left you behind to walk back,” he groused. I didn’t have a good answer so I didn’t say anything.
They shut off winter soon after that. The heat trap was turned on full force, the skies cleared and it was lovely. The first view I got of the Ganymede sky was a little after dawn next Sun phase. The heat trap made the sky a pale green but Jupiter shone right through it, ruddy orange, and big. Big and beautiful—I’ve never gotten tired of looking at Jupiter!
A harvest moon looks big, doesn’t it? Well, Jupiter from Ganymede is sixteen or seventeen times as wide as the Moon looks and it covers better than two hundred and fifty times as much sky. It hangs there in the sky, never rising, never setting, and you wonder what holds it up.
I saw it first in half-moon phase and I didn’t see how it could be any more beautiful than it was. But the Sun crept across the sky and a day later Jupiter was a crescent and better than ever. At the middle of Sun phase we went into eclipse, of course, and Jupiter was a great red, glowing ring in the sky, brightest where the Sun had just passed behind it.
But the best of all is during dark phase.
Maybe I ought to explain how the phases work; I know I didn’t understand it until I came to Ganymede. Ganymede is such a small planet and so close to its primary that it is tide-locked, just the way the Moon is; it keeps one face always toward Jupiter and therefore Jupiter does not move in the sky. The sun moves, the other Jovian moons move, the stars move—but not good old Jove; it just hangs there.
Ganymede takes just over an Earth week to revolve around Jupiter, so we have three and a half days of sunlight and then three and a half days of darkness. By Ganymede time the period of rotation is exactly one week; twenty-four Ganymede hours is one seventh of the period. This arrangement makes a Ganymede minute about a standard second longer than an Earth minute, but who cares? Except scientists, of course, and they have clocks that keep both sorts of time.
So here is the way a week goes on Ganymede: the Sun rises at Sunday midnight every week; when you get up Monday morning it’s a little above the eastern horizon and Jupiter is in half-moon phase. The Sun keeps climbing higher and about suppertime on Tuesday it slides behind Jupiter and Ganymede is in eclipse; eclipse can last an hour or so up to a maximum of about three hours and a half. The stars come out and Jupiter shows that beautiful red ring effect because of its thick atmosphere. Then it’s light again by bedtime Tuesday.