Nature Astronomy<\/a>.
While Pluto has a diameter of 1,477 miles (2,377 kilometers), 2002 XV93 only spans about 311 miles (500 kilometers) across.\n <\/p>\n\n The unexpected discovery \u2014 made by Dr. Ko Arimatsu, associate professor and senior lecturer at the National Astronomical Observatory of Japan, and his colleagues \u2014 could offer an unprecedented glimpse into how an atmosphere forms and remains around a small object, and change how astronomers think about objects in the Kuiper Belt.\n <\/p>\n
\n As January 2024 neared, Arimatsu and his colleagues prepared for the unique chance to observe a TNO as it passed in front of a bright star, as seen from Japan.\n <\/p>\n
\n 2002 XV93 has a standard orbit for a Kuiper Belt object and is smaller than a dwarf planet, so it wasn\u2019t considered to be different from other TNOs.\n <\/p>\n
\n But such moments when a TNO is illuminated by a star in the cosmic background, called stellar occultations, are rare opportunities to study the size, shape and features of a small, distant object, Arimatsu said. The researchers set up at three different locations across Japan, using observatories in Kyoto and the Nagano Prefecture, as well as a citizen scientist-run telescope in Fukushima.\n <\/p>\n
\n The star\u2019s light gradually faded as the TNO moved in front of it, suggesting the presence of of an atmosphere. If an object has no atmosphere, a star disappears and reappears much more sharply.\n <\/p>\n
\n \u201cThe observation data showed a smooth change of the star\u2019s brightness near the edge of the shadow, lasting about 1.5 seconds,\u201d Arimatsu wrote in an email. \u201cThis kind of smooth brightness change is naturally explained if the starlight was bent by a very thin atmosphere around the object.\u201d\n <\/p>\n
\n The researchers calculated that 2002 XV93 has an atmosphere about 5 million to 10 million times thinner than Earth\u2019s \u2014 and suspect two possibilities as to what created it.\n <\/p>\n
\n The atmosphere could be the product of cryovolcanoes on the small, icy body, which release internal gas such as methane, nitrogen or carbon monoxide from beneath its surface. Or, another Kuiper Belt object such as a comet might have struck 2002 XV93, also releasing gases from the subsurface.\n <\/p>\n
\n If the atmosphere was created due to impact, it may only last for several hundred years, Arimatsu said. But if regular cryovolcanic activity routinely replenishes the atmosphere with the release of gas, it could last much longer, he added.\n <\/p>\n
\n Future observations of 2002 XV93, either through more stellar occultation opportunities or by using the powerful James Webb Space Telescope, will help astronomers to better characterize the nature of the atmosphere and determine its origin, as well as how the atmosphere evolves over time.\n <\/p>\n
\n \u201cIf the future occultation observations reveal a steady decrease in the pressure, it would suggest a short-timescale impact origin,\u201d Arimatsu said.\n <\/p>\n
\n The Webb telescope also could detect methane or carbon monoxide emissions coming from the object and identify the atmosphere\u2019s composition.\n <\/p>\n
\n Arimatsu\u2019s team is continuing the search for atmospheres around other TNOs by relying on stellar occultation observations. Their findings could help determine if 2002 XV93 is a rare exception to the rule, or if other similar small objects also possess atmospheres.\n <\/p>\n
\n \u201cThis was an exciting discovery to read about,\u201d said Dr. Scott S. Sheppard, staff scientist at the Carnegie Institution for Science in Washington, DC. \u201cIt was thought that objects like 2002 XV93 would be too small to have an atmosphere, but this result shows that is not true.\u201d\n <\/p>\n
\n Sheppard did not participate in the research, but he has studied and discovered TNOs.\n <\/p>\n
\n The finding also highlights the discovery of recent activity on 2002 XV93, Sheppard noted, whether it be the eruption of frozen gases or the aftermath of material slowly falling back onto the object\u2019s surface.\n <\/p>\n
\n \u201cThis shows the Kuiper Belt is not a cold dead place,\u201d Sheppard wrote in an email, \u201cbut is teeming with activity and has many of the building blocks for life.\u201d\n <\/p>\n
\n Sign up for CNN\u2019s Wonder Theory science newsletter<\/a>. Explore the universe with news on fascinating discoveries, scientific advancements and more.<\/p>\n","protected":false},"excerpt":{"rendered":"Astronomers have detected a thin atmosphere around a tiny celestial body in the outer solar system for the…\n","protected":false},"author":2,"featured_media":624037,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48],"tags":[79,193],"class_list":["post-624036","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-science","tag-space"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/624036","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=624036"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/624036\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/624037"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=624036"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=624036"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=624036"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}