{"id":670060,"date":"2026-09-03T07:38:13","date_gmt":"2026-09-03T07:38:13","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/670060\/"},"modified":"2026-09-03T07:38:13","modified_gmt":"2026-09-03T07:38:13","slug":"astronomers-discover-decagonal-wave-circling-saturns-south-pole","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/670060\/","title":{"rendered":"Astronomers Discover Decagonal Wave circling Saturn\u2019s South Pole"},"content":{"rendered":"

For almost five decades, Saturn\u2019s north pole has been famous for hosting a bizarre, six-sided jet stream known as the hexagon<\/a>, a feature first spotted by NASA\u2019s Voyager spacecraft in the 1980s and still churning today. Astronomers had long wondered whether the ringed planet\u2019s southern hemisphere might hide a mirror-image structure. Now, it turns out the south pole has been quietly growing something of its own: a decagon.<\/strong><\/p>\n

\"These<\/a><\/p>\n

These Hubble images show Saturn and the gas giant\u2019s southern pole with its 10-sided atmospheric wave. Image credit: NASA \/ ESA \/ STScI \/ Agustin S\u00e1nchez-Lavega, UPV \/ Amy Simon, NASA\u2019s Goddard Space Flight Center \/ Michael Wong, UC Berkeley \/ Alyssa Pagan.<\/p>\n

Saturn\u2019s southern hemisphere dropped out of view from Earth in 2012 because of the planet\u2019s axial tilt, and didn\u2019t become observable again until 2023.<\/p>\n

When the images captured by the NASA\/ESA Hubble Space Telescope in October 2023 were examined, they showed a faint 10-vertex polygon near 63\u00b0S.<\/p>\n

By August 2024, the shape had sharpened, and by August-September 2025, Hubble and ground-based observers captured all 10 vertices fully formed, though their brightness contrast varied unevenly around the circle.<\/p>\n

The observations were taken as part of Hubble\u2019s Outer Planet Atmospheres Legacy (OPAL) program<\/a>, which has photographed the outer planets annually for more than a decade.<\/p>\n

\u201cWe\u2019ve never seen anything quite like this in Saturn\u2019s southern hemisphere,\u201d said OPAL principal investigator Dr. Amy Simon, an astronomer at NASA\u2019s Goddard Space Flight Center.<\/p>\n

\u201cThe northern hexagon has been there every time we\u2019ve looked for more than 40 years.\u201d<\/p>\n

\u201cThis feature is different \u2014 it appears to be strengthening, giving us the rare opportunity to watch a giant atmospheric pattern develop.\u201d<\/p>\n

\u201cGiven Saturn\u2019s symmetry in its north-south jet stream system, we have been searching for a counterpart to Saturn\u2019s northern hexagon on the south pole in Hubble images since 1990,\u201d said Dr. Agust\u00edn S\u00e1nchez-Lavega, an astronomer at the University of the Basque Country.<\/p>\n

\u201cImages from NASA\u2019s Cassini spacecraft, which orbited Saturn between 2004 and 2017, showed no inkling of a long-lived formation, either. The Hubble data confirmed the feature\u2019s presence back to 2023.\u201d<\/p>\n

The decagonal wave sits within one of Saturn\u2019s powerful jet streams and extends through multiple layers of the atmosphere, indicating it is not just a cloud-level feature, but a vertically extended atmospheric structure.<\/p>\n

\u201cThe most intriguing part to me is that this seems to have just formed recently,\u201d Dr. Simon said.<\/p>\n

\u201cThe question is, why did it suddenly form now when we haven\u2019t seen one before?\u201d<\/p>\n

\u201cFurther study is needed from Hubble and the NASA\/ESA\/CSA James Webb Space Telescope, as well as analysis of computer models, to understand how the decagon formed, how long it may last, and how it compares to the long-lived hexagon in the north.\u201d<\/p>\n

A paper<\/a> about the discovery was published today in the journal Science Advances.<\/p>\n

_____<\/p>\n

Agust\u00edn S\u00e1nchez-Lavega et al. 2026. A decagon wave around Saturn\u2019s south pole. Science Advances 12 (36); doi: 10.1126\/sciadv.aee4251<\/p>\n","protected":false},"excerpt":{"rendered":"For almost five decades, Saturn\u2019s north pole has been famous for hosting a bizarre, six-sided jet stream known…\n","protected":false},"author":2,"featured_media":670061,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[77],"tags":[1204,10210,93663,18,6145,10211,7446,19,17,1024,282942,1434,133,10214,28139],"class_list":["post-670060","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-planet","tag-atmosphere","tag-decagon","tag-eire","tag-esa","tag-gas-giant","tag-hubble","tag-ie","tag-ireland","tag-nasa","tag-opal-program","tag-saturn","tag-science","tag-solar-system","tag-wave"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/117205973071372645","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/670060","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=670060"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/670060\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/670061"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=670060"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=670060"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=670060"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}