The Desert Planet In 'Dune' Is Plausible, According To Science

The desert planet Arrakis in Frank Herbert's science fiction novel Dune is plausible, says Alexander Farnsworth, a climate modeler at the University of Bristol in England. According to Science News, the world would be a harsh place for humans to live, and they probably wouldn't have to worry about getting eaten by extraterrestrial helminths. From the report: For their Arrakis climate simulation, which you can explore at the website Climate Archive, Farnsworth and colleagues started with the well-known physics that drive weather and climate on Earth. Using our planet as a starting point makes sense, Farnsworth says, partly because Herbert drew inspiration for Arrakis from "some sort of semi-science of looking at dune systems on the Earth itself." The team then added nuggets of information about the planet from details in Herbert's novels and in the Dune Encyclopedia. According to that intel, the fictional planet's atmosphere is similar to Earth's with a couple of notable differences. Arrakis has less carbon dioxide in the atmosphere than Earth -- about 350 parts per million on the desert planet compared with 417 parts per million on Earth. But Dune has far more ozone in its lower atmosphere: 0.5 percent of the gases in the atmosphere compared to Earth's 0.000001 percent. All that extra ozone is crucial for understanding the planet. Ozone is a powerful greenhouse gas, about 65 times as potent at warming the atmosphere as carbon dioxide is, when measured over a 20-year period. "Arrakis would certainly have a much warmer atmosphere, even though it has less CO2 than Earth today," Farnsworth says. In addition to warming the planet, so much ozone in the lower atmosphere could be bad news. "For humans, that would be incredibly toxic, I think, almost fatal if you were to live under such conditions," Farnsworth says. People on Arrakis would probably have to rely on technology to scrub ozone from the air. Of course, ozone in the upper atmosphere could help shield Arrakis from harmful radiation from its star, Canopus. (Canopus is a real star also known as Alpha Carinae. It's visible in the Southern Hemisphere and is the second brightest star in the sky. Unfortunately for Dune fans, it isn't known to have planets.) If Arrakis were real, it would be located about as far from Canopus as Pluto is from the sun, Farnsworth says. But Canopus is a large white star calculated to be about 7,200 degrees Celsius. "That's significantly hotter than the sun," which runs about 2,000 degrees cooler, Farnsworth says. But "there's a lot of supposition and assumptions they made in here, and whether those are accurate numbers or not, I can't say." The climate simulation revealed that Arrakis probably wouldn't be exactly as Herbert described it. For instance, in one throwaway line, the author described polar ice caps receding in the summer heat. But Farnsworth and colleagues say it would be far too hot at the poles, about 70A C during the summer, for ice caps to exist at all. Plus, there would be too little precipitation to replenish the ice in the winter. High clouds and other processes would warm the atmosphere at the poles and keep it warmer than lower latitudes, especially in the summertime. Although Herbert's novels have people living in the midlatitudes and close to the poles, the extreme summer heat and bone-chilling -40C to -75C temperatures in the winters would make those regions nearly unlivable without technology, Farnsworth says. Temperatures in Arrakis' tropical latitudes would be relatively more pleasant at 45C in the warmest months and about 15C in colder months. On Earth, high humidity in the tropics makes it far warmer than at the poles. But on Arrakis, "most of the atmospheric moisture was essentially removed from the tropics," making even the scorching summers more tolerable. The poles are where clouds and the paltry amount of moisture gather and heat the atmosphere. But the tropics on Arrakis pose their own challenges. Hurricane force winds would regularly sandblast inhabitants and build dunes up to 250 meters tall, the researchers calculate. It doesn't mean people couldn't live on Arrakis, just that they'd need technology and lots of off-world support to bring in food and water, Farnsworth says. "I'd say it's a very livable world, just a very inhospitable world."

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