Williams and Pollard modeled climates of Earth’s twins with eccentricity up to 0.7, and provided a “weather forecast” for such a world. Periastron, located inside the orbit of Mercury, would occur on March 7th, with temperatures climbing quickly toward maximum on April 2nd. Interior areas of tropical continents would be close to the boiling point of water at this point, precluding survival of any unprotected lifeform, and warming oceans would sprout torrential storms. However, outside the tropics conditions would stay generally survivable, even mild in coastal areas. The extreme heat would cease quickly, and in about a month, life could return even to the equatorial landmasses. At apastron occurring in September, the climate would be mild in most places, and still cooling. The lowest temperatures would occur on 13th January, but except for polar areas, most of the planet would be still above freezing. By that time, the world would be speeding quickly inward, with just two months remaining to the rapid heating at periastron! Although this kind of annual cycle seems unusual for an earthling, many places would be comfortable even for human beings, and an Earth-like biosphere would probably thrive there without difficulty. Of course, this is just one specific example; other eccentric planets may exhibit very different climates depending on their orbits and physical characteristics. Amazingly, some simulations allow for habitable conditions even on planets with eccentricity of 0.9, almost as eccentric as planets can get. It seems likely that some other influence, such as tidal forces or stellar winds during periastron flybys, ruins planetary habitability before the temperature swings do.
Even when eccentricity itself might not limit habitability, long-term changes of orbital shape could. In cases when eccentricity oscillates wildly during eons, the average temperature would change, too, with increases of eccentricity leading to warming and circularization bringing cooling. Ice ages on Earth are—at least partially—caused by small changes in eccentricity. However, those shifts are insignificant compared to what some exoplanets must experience. What kind of biosphere could cope with such conditions?
Unlike gas giant planets, Earth-mass worlds are difficult to discover. Finding an Earth’s twin is a task for the next generation of astronomical instruments, and actually confirming its habitable nature would be even more challenging. Therefore, we still lack hard data about habitable exoplanets, eccentric or otherwise, although we have many reasons to believe they actually exist. Maybe some of the known giant planets host terrestrial-sized moons, which could be as interesting as any planet.
Take a textbook example of an eccentric exoplanet, and one of the first discovered, 16 Cygni Bb. Gas giant heavier than Jupiter, it orbits a Sun-like star on a highly eccentric orbit. There are two other stars in the system, too—a second Sun-like star and a red dwarf. Those companions have probably driven the planetary eccentricity to the present extreme value, and may cause it to fluctuate periodically in a wide range, although with a period of millions or even billions of years. The planetary orbit closely matches the hypothetical eccentric Earth of Williams and Pollard in both shape and average temperature. If 16 Cygni Bb has a satellite large enough to hold atmosphere, it could conceivably have liquid oceans and even host complex life on the surface. The locals would enjoy a fantastic view—three suns in the sky, with the main one periodically growing and shrinking on the sky, bringing short but fierce “summers” and long, mild winters.
We don’t know how common eccentric habitable planets and moons are, but we have all the reasons to believe their existence is far from impossible. Even the wilder planetary systems should not be excluded from our searches for life and Earth-like planets—at least until we learn much more about them. Because we live in a universe much more diverse than we’ve ever dreamed, and we have yet to find out whether or not there are biospheres as plentiful, as exotic, and as strange as the variety of worlds they could possibly inhabit.
About the Author
Tomas Petrasek, born 1984, is a Czech scientist, astronomy advocate and science fiction writer. He has published two non-fiction books about astronomy, one novel, and several short stories. He currently works as a neurobiologist at the Czech Academy of Sciences.
Digging in the Dirt:
A Conversation with Kim Stanley Robinson
Alvaro Zinos-Amaro
The first Kim Stanley Robinson novel I read was Icehenge (1984), back in the pre-Google days of 1997, when I had yet to graduate high school. The novel consists of three distinct first-person narrations, each structured as a diary or memoir, which must have seemed to my then self a far cry from the more dramatic, action-packed stories I was consuming. Though not immediately appealing, Icehenge challenged me to reconsider what I thought I knew about science fiction novels and thus made a much deeper mark on me than some of its more lithesome brethren. Later that same year I gobbled up Robinson’s wonderful The Wild Shore, The Gold Coast, and Pacific Edge, and the next year Red Mars, and the year after that—
You get the idea.
Sixteen years after reading Icehenge, I bumped into Stan at the bar of the 2013 WorldCon, in San Antonio, Texas, and a seemingly innocent remark I made about a panel led to one of those wonderful group conversations that rage on until three in the morning. Stan’s knowledge of literature, history, and science is staggering, but he wears his learning lightly. Stan’s anecdotes and reminiscences were informed by the same deep compassion and warmth of spirit that can be found in his many works of scientifically rigorous imaginative extrapolation.
Kim Stanley Robinson grew up in Southern California, was educated at UC San Diego and attended Clarion in 1975. He made his first sale to Damon Knight for his Orbit anthology, lived in Boston, Zurich, and Washington DC, then returned to Davis, California. He is married to Lisa Nowell and has two sons. He traveled to Antarctica in 1995 with the NSF. His work has been translated into twenty-four languages; 2312 was a New York Times bestseller; he has won two Hugos and three Nebulas, as well as the Locus, World Fantasy, and John W. Campbell awards.
Aurora, your latest novel, features a generation starship known simply as the Ship. Generation starships have been around in science fiction since at least Don Wilcox’s “The Voyage that Lasted 600 Years” (1940). Did you envision your novel in this tradition, or as something separate?
It sits in that tradition, which I quite enjoy. My first awareness of generation ships was through Robert Heinlein’s story “Universe” and Brian Aldiss’ Non-Stop, a classic of the genre. And then there was Gene Wolfe’s four-volume The Book of the Long Sun, my favorite Gene Wolfe novel sequence; it spills over into The Book of the Short Sun, which is three more novels, so it’s really a seven-book sequence, and I think it’s Wolfe’s greatest achievement, which is saying a lot, because he’s quite a power.
I was aware of all these but I also began to think that there was new scientific information, at levels biological, ecological, sociological, and psychological. I felt like you could tell a new story based on this new information, which is what science fiction is doing all the time. So I was looking to tell a new story and maybe even stick “a pin through a castle wall,” as Shakespeare puts it. Maybe pop the balloon, because the harder you press the idea, the more unlikely it looks that it can succeed.
Tau Ceti is nearby, and though it is not quite like our Sun, we know now that it has four large planets that you could call large Earths or small Neptunes. They’re too big to stand on without feeling five Earth gravities, but two of them are in the Goldilocks zone, where water would be liquid. I asked some people at NASA, “Could some of these big planets that we’ve found have moons that are almost the size of Earth?”
My NASA helpers told me that yes, but there’d be no way for us to distinguish two objects, from our distance and with our current methodology: a planet and its moon would look like one thing to us. So I invented Earth-sized moons for two of the planets we know are really there, planets E and F. That created all sorts of interesting problems, because moons that big orbiting planets that big will create a kind of tidal locking similar to o
ur Moon’s. It gets really complicated and interesting in terms of how much light you get, how often you get eclipses, and so on. An entire planetary ecology and astronomy was suggested just by that one little invention on my part.
That was all a lot of fun, and it turned out, when I read the Wikipedia article on Tau Ceti, that Asimov’s planet Aurora orbited Tau Ceti in The Naked Sun (1956), which I had not remembered, having read The Naked Sun forty years ago. I was really pleased by that, and it’s the reason my planet is called Aurora and my novel too; a little tip of the hat to Asimov. Also Ursula K. Le Guin, as in her The Dispossessed (1974), Anarres and Urras are also orbiting Tau Ceti.
What kind of conversation do you see your work having with science fiction classics such as the two you just mentioned?
I love to think of myself as working fully in the tradition. I’m a science fiction “patriot”; the field’s history is full of masterpieces and interesting works by brilliant writers, and people still read these works today. It’s a live canon, which people read for fun. It’s not just something that’s being taught in University courses. People read the science fiction canon on their own. I love that. I love being part of it.
My contribution is probably to bring the latest scientific information to old science fiction ideas and see what happens to the ideas when they’re tweaked with this new information. And then also just to do the English major thing—to think about form and characters, try to make good novels and add to the tradition.
How did you go about creating the protagonists of Aurora?
Practical questions of how to convey information often lead me to which characters I want to focus on. In the case of Aurora, I was doing a story of a starship voyage to Tau Ceti that was slower than light-speed, and never got faster than one-tenth of light-speed, and I wanted to start the story when they were approaching the Tau Ceti planetary system. I needed somebody who was young and had grown up entirely on the ship. It developed from there in a natural way that it could be the child of two people heavily involved in the running of the ship—the equivalent of a chief engineer and one of the lead medical people. So this child gets educated, and so does the reader, in a fairly rapid manner.
It also became quickly clear to me that it would be interesting if at a certain point the starship’s artificial intelligence—which would have to be really highly developed and powerful to help run a starship—became the narrator, and then had to learn to write a novel.
Your creative process for some novels, like The Years of Rice and Salt (2002), lasted years and involved reading dozens of books of research. When did you have the first inkling you wanted to tell the story of Aurora?
As far as I can remember, it was sometime during the last ten years. But going all the way back to Icehenge, I’ve been writing about saying good-bye to some small starship leaving the Solar System and headed for the stars. It happened in Icehenge, and Blue Mars (1996), and 2312 (2012) just a few years ago. It finally occurred to me that it was a story I doubted was possible. I wanted to think about that impression and tell a story and see what happened. About five years ago I started to put it in the pipeline as something I might do.
My editor, Tim Holman, was very encouraging. A lot of the research came down to the usual things: the Internet and books. But also, my friend Chris McKay at NASA Ames convened a crew of experts who helped me by answering a lot of questions.
We meet for lunch, I open my laptop, I ask questions, and they answer them and bounce ideas around. Sometimes that involves literal back-of-the-envelope calculations, and they suggest tweaks that are canny, sophisticated tweaks.
In the case of Aurora I had a new idea, possibly a new idea in all of science fiction—at least I don’t know of it ever being described before. So this is the climax of the novel, and has been cleared by people at NASA Ames. I think it was Chris who said, “Just make sure that in every equation you leave one crucial number out, and then no one can challenge you.”
While we’re on the subject of reading: Can you talk about your fascination with Virginia Woolf, and how it intersects—or doesn’t—with your interest in science fiction?
That’s a very good question. I came to Virginia Woolf late, because when I read her as an undergraduate I thought her work was boring and it made no sense to me. When I tried her most experimental novel, The Waves, as an adult, a middle-aged person, I realized this was fine literature concerning middle-aged people. I just hadn’t been prepared for it when I was young, when I wanted more excitement or drama or whatnot.
I started to read her and she turned out to be a very experimental novelist. Each novel is different; each novel is right at the edge of her ability to control it. It’s an experiment that she’s trying, and sometimes fails with, but most of the time she comes up with something extremely interesting.
Reading on, her non-fiction is exceptionally clear and well-judged. She’s a super clear writer, and she loves books so much she makes you want to read everything she writes about. She never has much of a negative word to say about anything. She’s taught me a lot.
Her biography was getting greatly expanded right during the years that I was getting interested in her work. She was the victim of some childhood sexual abuse by relatives, and had gone through some periods of mental illness as an adult, and had tempestuous relationships on all sides. It was a dramatic, high modernist life that was being unpacked by a succession of different biographers coming from different angles.
The best commentary of all was her own writing, in her diaries and letters. Hers is an incredibly documented life. There’s a book of people writing down memories of her, another of letters of condolence written to Leonard Woolf after she committed suicide, with all of his replies. So if you’re interested in a literary figure you could hardly pick a better one, because the documentation is huge, and she herself is such an interesting, vibrant, and lovely character. With very powerful literary judgment. She was a kind of literary genius.
I still have two books to read: her second novel, Night and Day, and a book called Flush, which is her fictional biography of Elizabeth Barrett Browning’s dog, a kind of side-project for her. I want to read those two books, and then I will have read everything by her, and most of the biographies of her. It’s an integrated project, and I think those are valuable, but you can only take on a few of them because they take up so much time.
It’s interesting to watch Virginia Woolf encounter science fiction in the figure of Olaf Stapledon. When I talk publicly about Woolf it’s usually in this context. She read Star Maker, and Last and First Men also, and she admired them tremendously. She had no prejudices in literature, thus not against science fiction, which hadn’t even been named as far as she was concerned. She took Stapledon as just another experimental writer, doing stuff that she herself wanted to do, which was to write about deep time. It was lovely to watch her try to incorporate deep time in her last two novels, The Years and Between the Acts.
I think I’m seeing this science fiction thread in Virginia Woolf’s literary biography, which has not been noticed by the huge mass of Woolf criticism that exists. Her letters to Stapledon are not in her collected letters, so it’s been overlooked. I feel like I ought to write a short note to the Virginia Woolf journals and tip them to this, so that real scholars can go in deeper. But I’m in no rush.
Another massive reading endeavor of yours was the complete Journals of Henry David Thoreau. What was that experience like?
That’s been beautiful. Like Woolf, Thoreau was a tremendously good prose writer. That’s what the two of them have in common. They both wrote diaries that were extensive accounts of their own lives and thinking, far beyond what most people do. So they’re the two greatest diarists. Beyond that, there are not too many similarities between the two.
He was a small-town guy in 19th century Massachusetts. It wasn’t exactly provincial because the intellectual leaders of the transcendentalist movement were there in the same town with him, so it was a very high-powered
intellectual atmosphere. Thoreau was also an early citizen scientist. He was interested in botany and in landscape, obsessively so. He had social anxieties and he was a very odd guy, but what he found was writing, daily writing as a practice, like a religion.
The Journals are simply superb. I read them slowly, a couple of days per reading session. I read them almost at the same speed at which Thoreau wrote them. I have no desires here except to enjoy this window into another mind, into a landscape writer of tremendous power.
I do hope someday to do my “best of” the Journals. There are now at least a dozen, maybe twenty extracts from his journals. They’re seven thousand pages long, maybe four million words. Naturally people have tried to give you different aspects of it: Thoreau on birds, Thoreau on his neighbors, Thoreau on writing, on botany, on one thing or another, including several “best-of’s.” It’s probably a mistake, but I’m making it too: I want to do Stan’s favorite passages from Thoreau’s Journals. But I only got the idea when I was halfway through, so having finished it I had to go back to the beginning and start over again, marking passages in the first half.
This is one of my retirement projects. It has to do with my mountain interests and nature writing more generally. That creeps over into my science fiction, and the two inform each other, but they’re not quite the same thing.
Speaking of your mountain interests: Given your passion about the Sierra Nevada, do you think you might write a book about it?
I sure hope so. It’s high on my list of things to do.
I’ve just signed a contract for three new novels, and I’m happy with that, because I have the ideas and I know what I’m up to, though I don’t want to talk about them right now. What I’m thinking is that when those books are done, I’m going to take pause and write my Sierra Nevada book, or try to. I’m going to put a solid effort into it. I’ll write about John Muir, who was a disciple of Thoreau’s, among other things. And I’ll write about what it’s like to be in the Sierra, with some route advice: “Go here, or go there, and you’ll like it.” A little bit about backpacking and how do it.
Clarkesworld Magazine Issue 106 Page 16