Earth\u2019s ocean of magma was full of oxygen. In a paper<\/a> published in 2023, three scientists wondered what might happen if the hydrogen in a planet\u2019s atmosphere and the oxygen in its magma were to mix \u2014 somehow. Hydrogen doesn\u2019t just spontaneously bind to oxygen, so they aren\u2019t the most willing chemical partners. Still, the researchers concluded that such a process would let a planet make its own water; they just weren\u2019t sure how much.<\/p>\n Two years later, they were thrown a lifeline by an ambitious set of experiments built by the researchers Harrison Horn<\/a>, a physicist at Lawrence Livermore National Laboratory; S.-H. Dan Shim<\/a>, a geophysicist at Arizona State University; and others.<\/p>\n Harrison Horn and collaborators built experiments to test whether hydrogen and oxygen could combine to form water on a type of exoplanet called a sub-Neptune.<\/p>\n Courtesy of Harrison Horn<\/p>\n Among other things, they wanted to know how sub-Neptunes, commonplace exoplanets two to four times the diameter of Earth, can have atmospheres rich in water, as telescopic observations suggest, even when they hew close to their scorching-hot host stars. Could a reaction between a hydrogen atmosphere and a magma ocean be enough?<\/p>\n They suspected it could, but only if a huge amount of hydrogen put the magma under a sufficient amount of pressure. \u201cThat higher pressure is a big part of what facilitates the water production,\u201d Horn said. \u201cIt actually enhances the chemical reactions.\u201d<\/p>\n To test their model, the team wanted to re-create the extreme (and extremely dangerous) conditions present on adolescent sub-Neptunes. They needed to put hydrogen, a highly flammable gas, under intense pressure using special tools called diamond anvils, and then combine it with rock samples melted with lasers. It took them five years to develop the techniques they needed to conduct these experiments safely and effectively. \u201cWe broke a lot of diamonds,\u201d Shim said. \u201cIt was an exciting journey.\u201d<\/p>\n They had hoped the hydrogen and oxygen would react to make water. And that\u2019s what happened, to the extreme: The reaction of high-pressure hydrogen and laser-melted rock was so efficient that it made up to 1,000 times more water<\/a> than scientists predicted. (A second laboratory study<\/a>, published around the same time, reported similar results.) \u201cIt doesn\u2019t seem unreasonable [that you could] produce a huge amount of water quite quickly,\u201d said Paul Byrne<\/a>, a planetary scientist at Washington University in St. Louis. And \u201cthis is all homegrown, indigenous water\u201d\u2014 no comets or asteroids required.\u00a0<\/p>\n Does that mean Earth created its own oceans? This is where the waters get a little murky. \u201cThe paper doesn\u2019t make strong claims about Earth,\u201d Horn said. But both he and Shim think it\u2019s a valid link to make. \u201cIt could happen,\u201d Shim said.<\/p>\n Other scientists agree that some amount of water could have formed on Earth \u2014 but perhaps not nearly enough to produce its oceans. \u201cI\u2019d say it\u2019s certainly possible that some water could be generated by reaction with hydrogen early on,\u201d said Quentin Williams<\/a>, an experimental geophysicist at the University of California, Santa Cruz. \u201cHow much might be generated is, however, pretty enigmatic.\u201d<\/p>\n The issue is that nobody knows if there was enough hydrogen in Earth\u2019s early atmosphere to create the pressure the reaction seems to need. Sub-Neptunes are far more massive than Earth, and their intense gravity is better at holding on to hydrogen. \u201cEarth is right on the edge of where that kind of thing can start happening,\u201d Horn said.<\/p>\n Some scientists don\u2019t think Earth had the heft to manufacture its own water at scale. \u201cI\u2019m a little bit doubtful whether you can have this for an Earth-mass planet,\u201d said Anders Johansen<\/a>, an astrophysicist at the University of Copenhagen in Denmark and at Lund University in Sweden. But, Byrne said, the sub-Neptune experiments suggest that the reaction wouldn\u2019t need to last long to create an enormous quantity of water. Earth might have been a water factory for only a moment, but that moment may have been enough to forge oceans.<\/p>\n If that\u2019s the case, then the implications stretch far beyond our own solar system. Perhaps countless planets meet what may be a necessary condition for hosting life because, as Byrne said, they \u201care born water-rich.\u201d<\/p>\n Drowning in a Sea of Possibilities\u00a0<\/p>\n It\u2019s possible that at least some of Earth\u2019s water came from processes on the planet. But that\u2019s not the end of the story: Comets are making a comeback.<\/p>\n By the time Rosetta met the duck-shaped comet 67P in 2014, scientists had studied the water of 11 other comets. All had D\/H ratios unlike Earth\u2019s \u2014 except one. In 2011, ESA\u2019s Herschel Space Observatory found<\/a> that the water in the comet Hartley 2 had a much more Earth-like signature.<\/p>\n","protected":false},"excerpt":{"rendered":"Hydrogen, Meet Magma\u00a0 When astronomers look at exoplanets \u2014 worlds outside our solar system \u2014 they see a…\n","protected":false},"author":2,"featured_media":490727,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[85,46,141,145],"class_list":["post-490726","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-il","tag-israel","tag-science","tag-space"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/490726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=490726"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/490726\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/490727"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=490726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=490726"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=490726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"Man](\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2026\/06\/Harrison-Horn-cr-Courtesy-of-Harrison-Horn.webp\")
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