{"id":191681,"date":"2025-11-21T00:47:09","date_gmt":"2025-11-21T00:47:09","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/191681\/"},"modified":"2025-11-21T00:47:09","modified_gmt":"2025-11-21T00:47:09","slug":"webb-spots-four-distinct-dust-shells-around-two-wolf-rayet-stars","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/191681\/","title":{"rendered":"Webb Spots Four Distinct Dust Shells around Two Wolf-Rayet Stars"},"content":{"rendered":"<p><strong>Using the NASA\/ESA\/CSA James Webb Space Telescope with data from ESO\u2019s Very Large Telescope (VLT), two team of astronomers have captured a mid-infrared image of a system of four serpentine spirals of dust around two aging Wolf-Rayet stars in a system known as <a href=\"https:\/\/simbad.cds.unistra.fr\/simbad\/sim-id?Ident=2XMM+J160050.7-514245\" target=\"_blank\" rel=\"noopener nofollow\">Apep<\/a> (2XMM J160050.7-514245).<\/strong><\/p>\n<p><a href=\"https:\/\/cdn.sci.news\/images\/enlarge13\/image_14369e-Apep.jpg\" rel=\"nofollow noopener\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-107360\" class=\"wp-image-107360 size-full\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/11\/image_14369-Apep.jpg\" alt=\"Webb\u2019s mid-infrared image shows four coiled shells of dust around a pair of Wolf-Rayet stars known as Apep. Image credit: NASA \/ ESA \/ CSA \/ STScI \/ Yinuo Han, Caltech \/ Ryan White, Macquarie University \/ Alyssa Pagan, STScI.\" width=\"580\" height=\"439\"  \/><\/a><\/p>\n<p id=\"caption-attachment-107360\" class=\"wp-caption-text\">Webb\u2019s mid-infrared image shows four coiled shells of dust around a pair of Wolf-Rayet stars known as Apep. Image credit: NASA \/ ESA \/ CSA \/ STScI \/ Yinuo Han, Caltech \/ Ryan White, Macquarie University \/ Alyssa Pagan, STScI.<\/p>\n<p>Wolf-Rayet stars are a rare class of massive binary stars, where the earliest carbon in the Universe is forged.<\/p>\n<p>Only a thousand are estimated to exist in our Milky Way galaxy, which contains hundreds of billions of stars overall.<\/p>\n<p>Of the few hundred Wolf-Rayet binaries that have been observed to date, the Apep system is the only example that contains two Wolf-Rayet stars of these types in our Milky Way Galaxy.<\/p>\n<p>In new research, Macquarie University astronomer Ryan White and colleagues aimed to refine the orbit of the Wolf-Rayet stars in the Apep system.<\/p>\n<p>They combined precise measurements of the ring location from the Webb image with the speed of the shells\u2019 expansion from observations taken by the VLT over eight years.<\/p>\n<p>\u201cThis is a one-of-a-kind system with an extremely long orbital period,\u201d White said.<\/p>\n<p>\u201cThe next longest orbit for a dusty Wolf-Rayet binary is about 30 years. Most have orbits between two to 10 years.\u201d<\/p>\n<p>The team\u2019s <a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4357\/adfbe1\" target=\"_blank\" rel=\"noopener nofollow\">paper<\/a> was published simultaneously in the Astrophysical Journal with another <a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/1538-4357\/ae12e5\" target=\"_blank\" rel=\"noopener nofollow\">paper<\/a>, led by Caltech astronomer Yinuo Han.<\/p>\n<p>\u201cLooking at the new Webb observations was like walking into a dark room and switching on the light \u2014 everything came into view,\u201d Dr. Han said.<\/p>\n<p>\u201cThere is dust everywhere in the Webb image, and the telescope shows that most of it was cast off in repetitive, predictable structures.\u201d<\/p>\n<p>The Webb observations delivered a first of its kind: a crisp mid-infrared image of a system of four serpentine spirals of dust, one expanding beyond the next in precisely the same pattern. Ground-based telescopes had only detected one shell before Webb revealed all four.<\/p>\n<p>The Webb image combined with several years of data from the VLT narrowed down how often the pair swing by one another: once every 190 years.<\/p>\n<p>Over each incredibly long orbit, the stars pass closely for 25 years and form dust.<\/p>\n<p>The Webb observations also confirmed that there are three stars gravitationally bound to one another in this system.<\/p>\n<p>The dust ejected by the two Wolf-Rayet stars is slashed by a third star, a massive supergiant, which carves a hole into each expanding cloud of dust from its wider orbit.<\/p>\n<p>\u201cWebb gave us the \u2018smoking gun\u2019 to prove the third star is gravitationally bound to this system,\u201d Dr. Han said.<\/p>\n<p>Researchers have known about the third star since the VLT observed the brightest innermost shell and the stars in 2018, but the Webb observations led to an updated geometric model, clinching the connection.<\/p>\n<p>\u201cWe solved several mysteries with Webb,\u201d Dr. Han said.<\/p>\n<p>\u201cThe remaining mystery is the precise distance to the stars from Earth, which will require future observations.\u201d<\/p>\n<p>_____<\/p>\n<p>Ryan M.T. White et al. 2025. The Serpent Eating Its Own Tail: Dust Destruction in the Apep Colliding Wind Nebula. ApJ 994, 121; doi: 10.3847\/1538-4357\/adfbe1<\/p>\n<p>Yinuo Han et al. 2025. The Formation and Evolution of Dust in the Colliding-wind Binary Apep Revealed by JWST. ApJ 994, 122; doi: 10.3847\/1538-4357\/ae12e5<\/p>\n","protected":false},"excerpt":{"rendered":"Using the NASA\/ESA\/CSA James Webb Space Telescope with data from ESO\u2019s Very Large Telescope (VLT), two team of&hellip;\n","protected":false},"author":2,"featured_media":191682,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[77],"tags":[106829,19915,15441,38025,18,6145,22912,19,17,1024,16274,133,37937,11186,106830,22917,15450,106831,106832],"class_list":{"0":"post-191681","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-apep","9":"tag-binary-star","10":"tag-csa","11":"tag-dust","12":"tag-eire","13":"tag-esa","14":"tag-eso","15":"tag-ie","16":"tag-ireland","17":"tag-nasa","18":"tag-nebula","19":"tag-science","20":"tag-shell","21":"tag-star","22":"tag-triple-star","23":"tag-vlt","24":"tag-webb","25":"tag-wind-nebula","26":"tag-wolf-rayet-star"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/115584935400985988","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/191681","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=191681"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/191681\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/191682"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=191681"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=191681"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=191681"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}