{"id":797250,"date":"2025-07-13T04:01:06","date_gmt":"2025-07-13T09:01:06","guid":{"rendered":"http:\/\/spaceweekly.com\/?p=797250"},"modified":"2025-07-13T04:01:06","modified_gmt":"2025-07-13T09:01:06","slug":"ancient-interstellar-object-3i-atlas-offers-first-glimpse-into-thick-disk-comet-chemistry","status":"publish","type":"post","link":"https:\/\/spaceweekly.com\/?p=797250","title":{"rendered":"Ancient interstellar object 3I\/ATLAS offers first glimpse into thick disk comet chemistry"},"content":{"rendered":"<p> <br \/>\n<\/p>\n<div>\n<p>Interstellar comet 3I\/ATLAS (C\/2025 N1) is now at the center of a coordinated international observational effort.<\/p>\n<p>With a hyperbolic orbit, high inbound velocity (~58\u202fkm\/s), and a projected perihelion of ~1.35\u202fAU on October 29\u201330, 2025, 3I\/ATLAS is the third confirmed object from outside the Solar System, following 1I\/\u02bbOumuamua and 2I\/Borisov.<\/p>\n<p>While past interstellar objects sparked interest due to their unusual shapes or activity, 3I\/ATLAS has drawn scientific focus for its likely origin in the Milky Way\u2019s ancient thick disk, a metal-poor galactic component populated by stars over 7 billion years old.<\/p>\n<p>Preliminary kinematic modeling published in a preprint by researchers at Michigan State University, Oxford, and others suggests the object may preserve the chemical and isotopic signatures of a primordial disk environment, distinct from the Solar System.<\/p>\n<figure class=\"wp-block-video\"><video controls=\"\" loop=\"\" playsinline=\"\" class=\"perfmatters-lazy\" data-src=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/Comet-3I-ATLAS.webm\"\/><noscript><video controls=\"\" loop=\"\" src=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/Comet-3I-ATLAS.webm\" playsinline=\"\"\/><\/noscript><figcaption class=\"wp-element-caption\">Animation shows the observations of comet 3I\/ATLAS when it was discovered on July 1, 2025. The NASA-funded ATLAS survey telescope in Chile first reported that the comet originated from interstellar space. Credit: ATLAS\/University of Hawaii\/NASA<\/figcaption><\/figure>\n<p>Unlike the carbon-rich 2I\/Borisov, 3I\/ATLAS appears to be dominated by water ice. This difference in volatile content may reflect its origin in a region with a lower metallicity and fewer complex organic molecules. Its red coma coloration, consistent with irradiated trans-Neptunian bodies, further implies a long interstellar residency before Solar System entry.<\/p>\n<p>Upcoming spectroscopic campaigns using the Hubble Space Telescope and James Webb Space Telescope aim to measure molecular abundances (H<sub>2<\/sub>O, CO, CO<sub>2<\/sub>), isotopic ratios, and dust properties.<\/p>\n<p>The data may provide constraints on the chemical environment of the early thick disk and help assess whether interstellar comets seeded planetary systems throughout the galaxy with volatiles essential for habitability.<\/p>\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<div class=\"wp-block-embed__wrapper\">\n<div class=\"perfmatters-lazy-youtube\" data-src=\"https:\/\/www.youtube.com\/embed\/IXJ221XXPvM\" data-id=\"IXJ221XXPvM\" data-query=\"feature=oembed\" onclick=\"perfmattersLazyLoadYouTube(this);\">\n<div><\/div>\n<\/div>\n<p><noscript><iframe loading=\"lazy\" title=\"VLT timelapse of 3I\/ATLAS, a new interstellar object\" width=\"1110\" height=\"624\" src=\"https:\/\/www.youtube.com\/embed\/IXJ221XXPvM?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/noscript>\n<\/div>\n<\/figure>\n<p>The object\u2019s large estimated coma-dominated diameter, potentially up to 24\u202fkm (15 mileS), combined with its preserved structure, makes it a unique laboratory for studying galactic chemical evolution. If its composition reflects the conditions around thick-disk stars, 3I\/ATLAS may become the first direct sample of water-rich material from beyond the thin disk where the Sun formed.<\/p>\n<p>Its closest approach to Earth, at ~1.8\u202fAU on December 19, 2025, presents no threat, but offers a rare window for Earth-based instruments to analyze material from deep galactic time.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"667\" alt=\"This diagram shows the trajectory of interstellar comet 3I\/ATLAS as it passes through the solar system. It will make its closest approach to the Sun in October. Credit: NASA\/JPL-Caltech\" class=\"wp-image-228300 perfmatters-lazy\" src=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1024x667.webp\" srcset=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1024x667.webp 1024w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-300x195.webp 300w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-768x500.webp 768w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1536x1001.webp 1536w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit.webp 1840w\" data-sizes=\"(max-width: 1024px) 100vw, 1024px\"\/><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"667\" src=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1024x667.webp\" alt=\"This diagram shows the trajectory of interstellar comet 3I\/ATLAS as it passes through the solar system. It will make its closest approach to the Sun in October. Credit: NASA\/JPL-Caltech\" class=\"wp-image-228300\" srcset=\"https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1024x667.webp 1024w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-300x195.webp 300w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-768x500.webp 768w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit-1536x1001.webp 1536w, https:\/\/watchers.news\/wp-content\/uploads\/2025\/07\/3I_interstellar-comet-orbit.webp 1840w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\"\/><figcaption class=\"wp-element-caption\">Diagram shows the trajectory of interstellar comet 3I\/ATLAS as it passes through the solar system. It will make its closest approach to the Sun in October. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n<\/div>\n<p><!-- MOLONGUI AUTHORSHIP PLUGIN 5.1.0 --><br \/>\n<!-- https:\/\/www.molongui.com\/wordpress-plugin-post-authors --><\/p>\n<\/div>\n<p><br \/>\n<br \/><a href=\"https:\/\/watchers.news\/2025\/07\/13\/ancient-interstellar-object-3i-atlas-glimpse-into-thick-disk-comet-chemistry\/?rand=772151\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Interstellar comet 3I\/ATLAS (C\/2025 N1) is now at the center of a coordinated international observational effort. With a hyperbolic orbit, high inbound velocity (~58\u202fkm\/s), and a projected perihelion of ~1.35\u202fAU&hellip; <\/p>\n","protected":false},"author":1,"featured_media":797251,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[],"class_list":["post-797250","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-genaero"],"_links":{"self":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/797250","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=797250"}],"version-history":[{"count":0,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/797250\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/media\/797251"}],"wp:attachment":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=797250"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=797250"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=797250"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}