![\"Neptune's](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2026\/06\/Nereid1989.jpg\")
Our best ever image of Nereid, taken by the Voyager 2 probe in 1989. (NASA\/JPL<\/a>)<\/p>\nOriginally discovered in 1949 by Gerard Kuiper (after whom the Kuiper Belt is named), over 100 years after Triton was discovered, it remained Neptune’s only other known moon until the Voyager 2 flyby in 1989.<\/p>\n
But its orbit is eccentric to say the least.<\/p>\n
It’s highly elliptical and lasts 360 days, making astronomers believe for years that it was another captured KBO.<\/p>\n
This new study pretty clearly shows that it is not.<\/p>\n
To prove that, the authors turned JWST’s high-resolution infrared camera toward Nereid for the first time. They found that it looks much more like an icy native moon of Uranus<\/a> or Saturn<\/a> than a dark, dusty captured KBO.<\/p>\n Compared with Phoebe, a known captured KBO, Nereid’s water-rich craters appear completely different in infrared light.<\/p>\n As the authors note in their paper<\/a>, “Nereid’s unique spectrum among outer Solar System bodies is not consistent with a scenario where Nereid is captured during the early Solar System’s dynamic instability.”<\/p>\n So that pretty much rules out the possibility of Nereid as a KBO, which leaves the only other option as a naturally occurring moon of Neptune.<\/p>\n But why such a weird orbit?<\/p>\n Its distance, ellipticality, and other factors are different from most other moons in the Solar System. To answer this question, the authors turned to simulations.<\/p>\n They used a dynamic simulator called REBOUND to map Neptune as a series of normal, circular moons.<\/p>\n Then they hit that nice, neat model with Triton.<\/p>\n As the captured KBO entered a highly eccentric, backward orbit, it wreaked absolute havoc with Neptune’s existing moon systems.<\/p>\n Most of the original moons were smashed to pieces or ejected from the system altogether as part of this process.<\/p>\n Their debris eventually settled down to create Neptune’s current ring system, and some of the tiny “ring-moons” like Proteus.<\/p>\n But the simulations also showed another feature.<\/p>\n In about 20% of all simulation runs, Triton kicked one of the native inner moons that was there before its arrival into a stable, highly elongated, tilted orbit. Just like Nereid’s.<\/p>\n So, in simulation at least, Nereid appears to be an original moon of Neptune that was kicked to its current wacky orbit by the capture of the planetary system’s biggest current resident.<\/p>\n If that’s the case, it could offer pristine insight into the formation of the Neptunian system, since its distant orbit would have kept it relatively well preserved compared to other gas giant moons.<\/p>\n We likely won’t be able to confirm that theory until we send another probe that way, though.<\/p>\n Related: A Lost World Almost as Big as Mars May Have Once Orbited Our Sun<\/a><\/p>\n Planetary scientists have been clamoring for one for over a decade, to no avail as of yet.<\/p>\n But until we do, we can shift our thinking of this specific gas giant moon from that of a captured ice ball to a battle-scarred survivor of one of the most violent moonpocalypses the Solar System has ever witnessed.<\/p>\n The research has been published in Science Advances<\/a>.<\/p>\n This article was originally published by Universe Today<\/a>. Read the original article<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Neptune is definitely the odd one out of the gas giants. It’s tilted at a strange angle, and…\n","protected":false},"author":2,"featured_media":736427,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[49,48,66,306],"class_list":["post-736426","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-ca","tag-canada","tag-science","tag-space"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/736426","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=736426"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/736426\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/736427"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=736426"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=736426"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=736426"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"YouTube](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2026\/06\/1781451250_673_0.jpg\")
frameborder=”0\u2033 allow=”accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share” referrerpolicy=”strict-origin-when-cross-origin” allowfullscreen><\/p>\n![\"Subscribe](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2026\/05\/FOMO-1200x628-_Dont-miss-the-next-breakthrough_-cosmic-colourful-642x336.jpg\")
<\/a><\/p>\n![\"Neptune's](\"https:\/\/www.newsbeep.com\/ca\/wp-content\/uploads\/2026\/06\/global-color-mosaic-of-Triton.jpg\")
A global color mosaic of Triton, taken by Voyager 2 in 1989. (NASA\/JPL\/USGS<\/a>)<\/p>\n