Mission of Gravity
Apr. 20th, 2005 10:27 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mmcirvinI recently filled a gap in my classic-science-fiction education and got around to reading Hal Clement's Mission of Gravity, one of the seminal works in the specialized subgenre of hard science fiction. (It's currently back in print, with some related short stories and essays and the novel-length sequel Star Light, in an omnibus volume called Heavy Planet.)
Mission of Gravity, from the fifties, is his most famous novel, obviously a major inspiration for other writers such as Robert Forward, Larry Niven and Vernor Vinge. It takes place on the planet Mesklin, an enormous, rapidly spinning world shaped like a discus, whose gravity is three times Earth normal at the equator and 700 times Earth's at the poles, and which orbits its primary in a long cometary ellipse (Clement was inspired by claims of evidence of an unseen body in the 61 Cygni system). The day is minutes long; the atmosphere is hydrogen, with rains and oceans of methane. The intelligent Mesklinites are small, incredibly tough, centipede-like creatures at a roughly medieval level of technology. Psychologically, they are very humanlike beings, though they have some unusual attitudes resulting from their high-gravity environment (the polar Mesklinites have never heard of thrown weapons and won't readily get under any solid object). In a storytelling device that Clement would use over and over throughout his career, the story revolves around the mostly friendly cooperation between a band of adventuring Mesklinite sailors and a group of humans, who send them on an errand to recover a malfunctioning scientific lander at the pole.
Clement makes no attempt to be a prose stylist; he was a high-school science teacher, the careful imagination of Mesklin's bizarre environment is the story's central jewel, and his writing is simple and declarative, with long didactic passages betraying a particular fascination for chemistry and geology. I found it strangely comforting, though I doubt it will be to everyone's taste. In the early parts of the book, a heavily-armored human actually travels with the sailors near the equator of Mesklin, and there are frequent point-of-view shifts that are not always handled well. Once they part company and the story follows the Mesklinites on their danger-filled odyssey back toward the pole, Clement's storytelling becomes considerably more graceful and absorbing, and while his characters never entirely become three-dimensional, his Mesklinite trader-captain and some of his crew are portrayed with considerable affection. The end of the book surprised me: the alien captain delivers a speech to the faraway humans that is profoundly moving in a way that perhaps only a high-school science teacher could manage.
Even the most imaginative of science-fiction authors usually dream up imaginary planets that are not too far off from what's available in our solar system. Clement was not like that. His planets, in these and his other stories (such as the novels Close to Critical and Iceworld, which I'd read earlier), were usually profoundly physically different from anything we've got here, and in this he was prescient; it's increasingly clear that our solar system is not all that typical, and extremely weird planets are common. I'm glad that Clement lived just long enough to see the beginning of the modern spate of extrasolar planet discoveries (and write some stories inspired by them). We now know that the universe is full of Hal Clement planets.
Mission of Gravity, from the fifties, is his most famous novel, obviously a major inspiration for other writers such as Robert Forward, Larry Niven and Vernor Vinge. It takes place on the planet Mesklin, an enormous, rapidly spinning world shaped like a discus, whose gravity is three times Earth normal at the equator and 700 times Earth's at the poles, and which orbits its primary in a long cometary ellipse (Clement was inspired by claims of evidence of an unseen body in the 61 Cygni system). The day is minutes long; the atmosphere is hydrogen, with rains and oceans of methane. The intelligent Mesklinites are small, incredibly tough, centipede-like creatures at a roughly medieval level of technology. Psychologically, they are very humanlike beings, though they have some unusual attitudes resulting from their high-gravity environment (the polar Mesklinites have never heard of thrown weapons and won't readily get under any solid object). In a storytelling device that Clement would use over and over throughout his career, the story revolves around the mostly friendly cooperation between a band of adventuring Mesklinite sailors and a group of humans, who send them on an errand to recover a malfunctioning scientific lander at the pole.
Clement makes no attempt to be a prose stylist; he was a high-school science teacher, the careful imagination of Mesklin's bizarre environment is the story's central jewel, and his writing is simple and declarative, with long didactic passages betraying a particular fascination for chemistry and geology. I found it strangely comforting, though I doubt it will be to everyone's taste. In the early parts of the book, a heavily-armored human actually travels with the sailors near the equator of Mesklin, and there are frequent point-of-view shifts that are not always handled well. Once they part company and the story follows the Mesklinites on their danger-filled odyssey back toward the pole, Clement's storytelling becomes considerably more graceful and absorbing, and while his characters never entirely become three-dimensional, his Mesklinite trader-captain and some of his crew are portrayed with considerable affection. The end of the book surprised me: the alien captain delivers a speech to the faraway humans that is profoundly moving in a way that perhaps only a high-school science teacher could manage.
Even the most imaginative of science-fiction authors usually dream up imaginary planets that are not too far off from what's available in our solar system. Clement was not like that. His planets, in these and his other stories (such as the novels Close to Critical and Iceworld, which I'd read earlier), were usually profoundly physically different from anything we've got here, and in this he was prescient; it's increasingly clear that our solar system is not all that typical, and extremely weird planets are common. I'm glad that Clement lived just long enough to see the beginning of the modern spate of extrasolar planet discoveries (and write some stories inspired by them). We now know that the universe is full of Hal Clement planets.
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no subject
Date: 2005-04-20 10:56 pm (UTC)no subject
Date: 2005-04-21 05:10 am (UTC)I don't really have the energy to keep on top of the extra-solar planet game, but it's never been clear to me how much of this is a real effect, and how much is selection bias. That is, we're mostly detecting really weird solar systems because the only things we can easily detect are really weird.
I don't think we'd have any real way to pick up a Jupiter-sized planet in a Jupiter-like orbit, which makes it very unlikely that we'd be able to find a solar system like ours, even if we were looking at the right star.
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Date: 2005-04-21 05:35 am (UTC)There's one datum available today that makes me think that solar systems like ours really are unusual, beyond selection-bias effects: Most the extrasolar planets found so far have relatively large orbital eccentricities, and that isn't needed for detection. That's interesting in that people working on planetary formation have done a lot of work on how systems of nearly circular orbits could emerge through a kind of natural selection. But it appears that they're far from inevitable.
It could be that this is a weak anthropic effect, that is, you're not going to get civilizations arising on planets unless things are relatively well-behaved. But I've always been slightly suspicious of such arguments; the world is usually weirder and more various than we imagine. Of course I have my own wishful aesthetics; I hope that if there are intelligent aliens out there, they're totally bizarre by our standards and live in completely non-Earthlike hellholes, because that would be more interesting than a bunch of bumpy-head humanoids.
no subject
Date: 2005-04-21 06:37 am (UTC)You could probably argue (and I'm sure people have tried to, in parts of the literature that I don't follow) that this is an indication that there's something else going on that pushes gas giants into weird orbits. Of course, that would require that process, whatever it is, to be unexpectedly common, which just pushes the question back a level.
no subject
Date: 2005-04-21 06:39 am (UTC)