--- title: "Exoplanet “Water Worlds” Could Hold Unfathomably Deep Alien Oceans" description: "A new theory suggests that a type of exoplanet two to four times the size of Earth (\"sub-Neptunes\") is likely to be a water world, not a gas dwarf." date: "2019-05-01" modified: "2019-05-01" authors: - name: "Victor Tangermann" job_title: "Senior Editor" link: "https://futurism.com/authors/victor" url: "https://futurism.com/exoplanet-water-worlds-deep-oceans" categories: - "Astronomy" - "Exoplanets" - "Space" tags: - "exoplanet" - "Exoplanets" - "kepler telescope" - "liquid oceans" --- # Exoplanet “Water Worlds” Could Hold Unfathomably Deep Alien Oceans ![A new theory suggests that a type of exoplanet two to four times the size of Earth ("sub-Neptunes") is likely to be a water world, not a gas dwarf.]() *\Image: NASA\* ## Water Worlds Scientists have already spotted [thousands of exoplanets]() — planets that orbit a star outside of the Solar System — and many have the [potential to harbor life](). A wild new theory suggests that exoplanets two to four times the size of Earth, known as "sub-Neptunes," are likely to be water worlds rather than gas dwarfs — and their oceans could be so deep that they almost defy comprehension. Instead of a few kilometers deep, like Earth's oceans, Harvard researcher Li Zeng said that these alien oceans could be "hundreds or thousands of kilometers" in depth, [according to *Gizmodo*](). "Unfathomable. Bottomless. Very Deep." ## Ice Limit The new research, [published]() in the journal *Proceedings of the National Academy of Sciences,* used a complex computer model that examined data collected by the Kepler Space Telescope — NASA's exoplanet hunting device — and the Gaia mission, the European Space Agency's space telescope*.* The results are astonishing: the findings indicate that some exoplanets may contain "as much as 50 percent water." That's vastly more than on Earth, where water takes up just 0.02 percent of the planet's mass. The pressure would be so dizzyingly high, in fact, that much of the water would turn to hard ice. "It was a huge surprise to realize that there must be so many water-worlds," Zeng said in a 2018 [press release](). **READ MORE:** [Water Worlds Could Have Mind-Bogglingly Deep Oceans, New Models Suggest]() \[*Gizmodo*\] More on exoplanets: [*New Method Could Help Astronomers Find Life-Supporting Exoplanets*]() ## Author I've been at Futurism since 2017, where my role has evolved to encompass design, writing, and increasingly editing. I've always been fascinated by space exploration and advanced transportation, which I've leaned into by interviewing luminaries in those fields while closely following the dimensions of policy and regulation that allow next-generation projects to succeed -- or, sometimes, to fail. I'm also keenly interested in the effects of generative AI on society, policies, and democratic institutions, as well as clean energy, physics and biology, and the vagaries of tech leadership. My work for Futurism has been cited by publications including Ars Technica, Gizmodo, PC Magazine, Jalopnik, Fox News, and the New York Post. I spent my childhood living in locations including Manila, the Philippines, and Geneva, Switzerland, attended McGill University, and now live in Toronto, Canada. Before Futurism I worked at AskMen and a small photography studio. In my free time, I'm an avid gardener, foodie, and craft beer lover, as well as a maker of artisanal hot pepper sauces. I have a magnificent dog named Freida. ### Author social links [Bluesky]()