The Makeshift Rocket II

I did not read anything else last night because of the TV coverage of Nelson Mandela's death.

Poul Anderson's The Makeshift Rocket (New York, 1962) has the gyrogravitics of his Tales Of The Flying Mountains and, I think, the same fictitious Martian race as his "Captive of the Centaurianess," although it does not belong in the same timeline as either of those works.

With gravity control, it would theoretically be possible to terraform the asteroids, as in Flying Mountains and here. First, it would be possible to give them enough gravity to hold a breathable atmosphere. Then, if there were also an adequate source of heat, soil and plants could be imported. However, this does read like a fantasy rather than a hard sf version of the Solar System:

"Beyond the little spacefield was a charming vista of green meadows, orderly hedgerows, cottages and bowers, a white gravel road. Just below the near, sharply curving horizon stood Grendel's only town; from this height could be seen a few roofs and the twin spires of St George's. The flag of the Kingdom, a Union Jack on a Royal Stuart field, fluttered there under a sky of darker blue than Earth's, a small remote sun and a few of the brightest stars. Grendel was a typical right little, tight little Anglian asteroid, peacefully readying for the vacation-season influx of tourists from Briarton, York, Scotia, Holm, New Winchester, and the other shires." (pp. 8-9)

This sounds as if it belongs in a magical realm of broomsticks and flying carpets. A very sharply curving horizon, I should think. Some blue in the sky, because of the atmosphere, but not much. Imagine what would happen if the gravity control failed. And who brought the Stuarts back? A worldlet with only one town but with easy transport to and from several other worldlets.

As always, Anderson thinks through the physics of his fictional technology. In order to hold the atmosphere, the gyrogravitic generators at the center of mass maintain one gee to an altitude of 2000 kilometers but thereafter the artificial attraction drops to zero within one kilometer. It is not easy for a spaceship with its negative force to cross this boundary - although HG Wells' Cavor might have felt at home here.