{"id":235670,"date":"2025-12-16T12:07:10","date_gmt":"2025-12-16T12:07:10","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/235670\/"},"modified":"2025-12-16T12:07:10","modified_gmt":"2025-12-16T12:07:10","slug":"researchers-question-methane-atmosphere-on-trappist-1e","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/235670\/","title":{"rendered":"Researchers question methane atmosphere on TRAPPIST-1e"},"content":{"rendered":"<p><img fetchpriority=\"high\" decoding=\"async\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/12\/TRAPPIST-1e-exoplanet-artist-concept-February-20-2018.png\" alt=\"Methane atmosphere on TRAPPIST-1e: Rocky planet with clouds and distant small, red sun, with 2 other planets tiny with distance.\" width=\"800\" height=\"559\" class=\"size-full wp-image-451327\"  \/>This is an artist\u2019s concept of <a href=\"https:\/\/earthsky.org\/astronomy-essentials\/what-are-exoplanets\/\" rel=\"noopener nofollow\" target=\"_blank\">exoplanet<\/a> TRAPPIST-1e, about <a href=\"https:\/\/earthsky.org\/astronomy-essentials\/how-far-is-a-light-year\" rel=\"noopener nofollow\" target=\"_blank\">40 light-years<\/a> from Earth. A new study urges caution when trying to determine if there is a methane atmosphere on <a href=\"https:\/\/science.nasa.gov\/exoplanet-catalog\/trappist-1-e\/\" rel=\"noopener nofollow\" target=\"_blank\">TRAPPIST-1e<\/a>, or any atmosphere at all. Image via <a href=\"https:\/\/solarsystem.nasa.gov\/news\/335\/10-things-all-about-trappist-1\/\" rel=\"noopener nofollow\" target=\"_blank\">NASA<\/a>.<\/p>\n<ul>\n<li><strong>Is there a methane-rich atmosphere on exoplanet TRAPPIST-1e?<\/strong> Recent results from the Webb space telescope hinted there might be.<\/li>\n<li><strong>But the tentative methane detection might be from the planet\u2019s star<\/strong> instead, a new paper suggests.<\/li>\n<li><strong>There could still be a thin atmosphere<\/strong> \u2013 without methane \u2013 but more observations are needed to know for sure.<\/li>\n<\/ul>\n<p><a href=\"https:\/\/earthskystore.org\/collections\/astronomy-tools\/products\/earthsky-lunar-calendar\" rel=\"noopener nofollow\" target=\"_blank\">EarthSky\u2019s 2026 lunar calendar is available now. Get yours today! Makes a great gift.<\/a><\/p>\n<p>Is there a methane atmosphere on TRAPPIST-1e?<\/p>\n<p>Last September, astronomers published two papers that <a href=\"https:\/\/earthsky.org\/space\/exoplanet-trappist-1e-exoplanets-james-webb-space-telescope-astrobiology\/\" rel=\"noopener nofollow\" target=\"_blank\">said<\/a> the Earth-sized <a href=\"https:\/\/earthsky.org\/astronomy-essentials\/what-are-exoplanets\" rel=\"noopener nofollow\" target=\"_blank\">exoplanet<\/a> TRAPPIST-1e might have a thin atmosphere of methane and nitrogen. On December 4, 2025, researchers released a third paper that urges caution about TRAPPIST-1e\u2019s possible atmosphere. The researchers <a href=\"https:\/\/news.arizona.edu\/news\/new-look-trappist-1e-earth-sized-habitable-zone-exoplanet\" rel=\"noopener nofollow\" target=\"_blank\">said<\/a> the new results from the <a href=\"https:\/\/science.nasa.gov\/mission\/webb\/\" rel=\"noopener nofollow\" target=\"_blank\">James Webb Space Telescope<\/a> suggest the preliminary hint of a methane-rich atmosphere might be erroneous. But that doesn\u2019t necessarily mean the planet has no atmosphere at all. It does, however, show that characterizing that atmosphere \u2013 if it exists \u2013 isn\u2019t easy.<\/p>\n<p><a href=\"https:\/\/lpl.arizona.edu\/faculty\/sukrit-ranjan\" rel=\"noopener nofollow\" target=\"_blank\">Sukrit Ranjan<\/a> at the Lunar and Planetary Laboratory at the University of Arizona is the lead author of the new paper and was involved with the previous two papers as well. The new paper focuses on \u201cwarm exo-Titans\u201d and uses TRAPPIST-1e as a test case. Such planets are hypothesized to be warmer versions of Saturn\u2019s moon Titan, with nitrogen and methane atmospheres. That\u2019s because they orbit close to their stars, unlike Titan in our outer solar system.<\/p>\n<p>The researchers <a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/ae1026\" rel=\"noopener nofollow\" target=\"_blank\">published<\/a> the new <a href=\"https:\/\/iopscience.iop.org\/journal\/2041-8205\/page\/about-the-journal#peer\" rel=\"noopener nofollow\" target=\"_blank\">peer-reviewed<\/a> paper in The Astrophysical Journal Letters on November 3, 2025.<\/p>\n<blockquote class=\"bluesky-embed\" data-bluesky-uri=\"at:\/\/did:plc:6hpos2szojcsikkzdyur5xy6\/app.bsky.feed.post\/3m7b3rdtkh22t\" data-bluesky-cid=\"bafyreicob6yhhb4n2ghbacgbifdsyxlfm6v6xuryalaufrjvmr2n2lh4py\">\n<p lang=\"en\">A New Look At TRAPPIST-1e, An Earth-sized, Habitable-zone Exoplanetastrobiology.com\/2025\/12\/a-ne\u2026 #astrobiology #exoplanet<\/p>\n<p>\u2014 <a href=\"https:\/\/bsky.app\/profile\/did:plc:6hpos2szojcsikkzdyur5xy6?ref_src=embed\" rel=\"nofollow noopener\" target=\"_blank\">Astrobiology (@astrobiology.bsky.social)<\/a> <a href=\"https:\/\/bsky.app\/profile\/did:plc:6hpos2szojcsikkzdyur5xy6\/post\/3m7b3rdtkh22t?ref_src=embed\" rel=\"nofollow noopener\" target=\"_blank\">2025-12-05T18:15:36.516Z<\/a><\/p>\n<\/blockquote>\n<p>Does TRAPPIST-1e have an atmosphere?<\/p>\n<p>Using Webb, scientists had already determined that TRAPPIST-1e doesn\u2019t have a thick <a href=\"https:\/\/en.wikipedia.org\/wiki\/Primary_atmosphere\" rel=\"noopener nofollow\" target=\"_blank\">primordial atmosphere<\/a>. That is the original atmosphere a planet develops when it first starts forming. TRAPPIST-1e could, however, now have a secondary thin atmosphere more like that of Earth. But that depends on whether intense solar bursts from the planet\u2019s <a href=\"https:\/\/earthsky.org\/astronomy-essentials\/what-is-a-red-dwarf-star-most-common\/\" rel=\"noopener nofollow\" target=\"_blank\">red dwarf star<\/a> have eroded any existing atmosphere or not.<\/p>\n<p>As reported last September, analysis of the Webb results hinted at a possible thin atmosphere of methane. A methane atmosphere would also likely require nitrogen to be maintained. It might, therefore, be similar to Titan\u2019s atmosphere, which is primarily nitrogen but also rich in methane. It could also be similar to Earth\u2019s nitrogen atmosphere, since it would be warmer than Titan\u2019s frigid atmosphere.<\/p>\n<p>The researchers used Webb\u2019s Near-Infrared Spectrograph (<a href=\"https:\/\/science.nasa.gov\/mission\/webb\/nirspec\/\" rel=\"noopener nofollow\" target=\"_blank\">NIRSpec<\/a>) instrument to analyze TRAPPIST-1e\u2019s <a href=\"https:\/\/earthsky.org\/space\/what-is-the-electromagnetic-spectrum\/\" rel=\"noopener nofollow\" target=\"_blank\">electromagnetic spectrum<\/a>, or wavelengths of light, as it passed in front of its star. If there is an atmosphere, the starlight will pass through it, which Webb can analyze. And the more of these passes in front of its star \u2013 or transits \u2013 it can observe, the better.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/12\/Sukrit-Ranjan-The-University-of-Arizona.jpg\" alt=\"Smiling man with short hair wearing a blue suit and checkered tie.\" width=\"500\" height=\"625\" class=\"size-full wp-image-530724\"  \/><a href=\"https:\/\/lpl.arizona.edu\/faculty\/sukrit-ranjan\" rel=\"noopener nofollow\" target=\"_blank\">Sukrit Ranjan<\/a> at The University of Arizona is the lead author of the new paper about methane on TRAPPIST-1e. Image via <a href=\"https:\/\/lpl.arizona.edu\/faculty\/sukrit-ranjan\" rel=\"noopener nofollow\" target=\"_blank\">The University of Arizona<\/a>.<br \/>\nIs methane on the planet or the star?<\/p>\n<p>Webb observed four transits in all, so far. That\u2019s when the tentative detection of methane was made. But it\u2019s possible that the star itself could also have methane molecules in its atmosphere. As Ranjan <a href=\"https:\/\/news.arizona.edu\/news\/new-look-trappist-1e-earth-sized-habitable-zone-exoplanet\" rel=\"noopener nofollow\" target=\"_blank\">explained<\/a>:<\/p>\n<blockquote>\n<p>While the sun is a bright, yellow dwarf star, TRAPPIST-1 is an ultracool red dwarf, meaning it is significantly smaller, cooler and dimmer than our sun. Cool enough, in fact, to allow for gas molecules in its atmosphere. We reported hints of methane, but the question is: Is the methane attributable to molecules in the atmosphere of the planet or in the host star?<\/p>\n<\/blockquote>\n<p>TRAPPIST-1e probably not an exo-Titan<\/p>\n<p>The researchers tested various scenarios to try to determine if the possible methane was in the planet\u2019s atmosphere or the star\u2019s.<\/p>\n<p>As it turned out, the most likely planetary scenario was the warm exo-Titan one. But that possibility is still less likely than the methane signal coming from the star. Yet that doesn\u2019t necessarily mean there\u2019s no atmosphere on TRAPPIST-1e at all. There could still be a thin atmosphere, just without any methane. Ranjan <a href=\"https:\/\/news.arizona.edu\/news\/new-look-trappist-1e-earth-sized-habitable-zone-exoplanet\" rel=\"noopener nofollow\" target=\"_blank\">said<\/a>:<\/p>\n<blockquote>\n<p>Based on our most recent work, we suggest that the previously reported tentative hint of an atmosphere is more likely to be \u2018noise\u2019 from the host star. However, this does not mean that TRAPPIST-1e does not have an atmosphere; we just need more data.<\/p>\n<\/blockquote>\n<p>As the paper <a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/ae1026\" rel=\"noopener nofollow\" target=\"_blank\">notes<\/a>:<\/p>\n<blockquote>\n<p>While they did not find a direct solar system analog, they noted that the favored atmospheric scenario was most comparable to a warm Titan, with other possible explanations for the signal being stellar activity or random noise. Here, we have performed a deeper investigation to determine the plausibility of the warm exo-Titan scenario through detailed photochemical modeling, which reveals that a warm exo-Titan TRAPPIST-1e is a priori unlikely due to the short methane lifetime. <\/p>\n<\/blockquote>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/12\/TRAPPIST-1-exoplanets-comparison-artist-concept-NASA.jpg\" alt=\"A row of 7 small, differently colored planets, with partial view of large reddish sun on left side.\" width=\"800\" height=\"400\" class=\"size-full wp-image-448583\"  \/><a href=\"https:\/\/cdn.eso.org\/images\/screen\/eso1706o.jpg\" rel=\"noopener nofollow\" target=\"_blank\">View larger<\/a>. | A size comparison of the planets of the <a href=\"https:\/\/earthsky.org\/space\/big-discovery-7-earth-sized-planets-orbit-nearby-star\/\" rel=\"noopener nofollow\" target=\"_blank\">TRAPPIST-1<\/a> system lined up in order of increasing distance from their host star (not to scale). The planetary surfaces are an artist\u2019s concept of what they might look like. Image via NASA\/ R. Hurt\/ T. Pyle\/ <a href=\"https:\/\/www.eso.org\/public\/images\/eso1706o\/\" rel=\"noopener nofollow\" target=\"_blank\">ESO<\/a>.<br \/>\nMore observations needed<\/p>\n<p>As Ranjan noted above, more observations of TRAPPIST-1e will be required to know for sure if it has a methane atmosphere, or any atmosphere. More transits seen by Webb will help. And NASA\u2019s upcoming <a href=\"https:\/\/science.nasa.gov\/mission\/pandora\/\" rel=\"noopener nofollow\" target=\"_blank\">Pandora<\/a> space telescope, scheduled to launch in 2026, will also be able to characterize the planet\u2019s atmosphere in more detail. Ranjan said:<\/p>\n<blockquote>\n<p>These observations will allow us to separate what the star is doing from what is going on in the planet\u2019s atmosphere, should it have one.<\/p>\n<\/blockquote>\n<p>Bottom line: Previous hints of a methane atmosphere on TRAPPIST-1e might not be accurate, a new paper suggests. But the tantalizing exoplanet could still have an atmosphere.<\/p>\n<p><a href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/ae1026\" rel=\"noopener nofollow\" target=\"_blank\">Source: The Photochemical Plausibility of Warm Exo-Titans Orbiting M Dwarf Stars<\/a><\/p>\n<p><a href=\"https:\/\/news.arizona.edu\/news\/new-look-trappist-1e-earth-sized-habitable-zone-exoplanet\" rel=\"noopener nofollow\" target=\"_blank\">Via The University of Arizona<\/a><\/p>\n<p><a href=\"https:\/\/earthsky.org\/space\/exoplanet-trappist-1e-exoplanets-james-webb-space-telescope-astrobiology\/\" rel=\"noopener nofollow\" target=\"_blank\">Read more: Exoplanet TRAPPIST-1e: New hints of a habitable world?<\/a><\/p>\n<p><a href=\"https:\/\/earthsky.org\/space\/trappist-1-exoplanets-atmospheres-habitability-webb\/\" rel=\"noopener nofollow\" target=\"_blank\">Read more: Some TRAPPIST-1 exoplanets could have stable atmospheres<\/a><\/p>\n<p>                    Paul Scott Anderson<br \/>\n                    <a href=\"https:\/\/earthsky.org\/author\/paul-scott-anderson\/\" class=\"post-author-link\" rel=\"nofollow noopener\" target=\"_blank\">View Articles<\/a><\/p>\n<p>                    About the Author:<\/p>\n<p>Paul Scott Anderson has had a passion for space exploration that began when he was a child when he watched Carl Sagan\u2019s Cosmos. He studied English, writing, art and computer\/publication design in high school and college. He later started his blog The Meridiani Journal in 2005, which was later renamed Planetaria. He also later started the blog Fermi Paradoxica, about the search for life elsewhere in the universe.&#13;<br \/>\n&#13;<br \/>\nWhile interested in all aspects of space exploration, his primary passion is planetary science and SETI. In 2011, he started writing about space on a freelance basis with Universe Today. He has also written for SpaceFlight Insider and AmericaSpace and has also been published in The Mars Quarterly. He also did some supplementary writing for the iOS app Exoplanet.&#13;<br \/>\n&#13;<br \/>\nHe has been writing for EarthSky since 2018, and also assists with proofing and social media.<\/p>\n","protected":false},"excerpt":{"rendered":"This is an artist\u2019s concept of exoplanet TRAPPIST-1e, about 40 light-years from Earth. A new study urges caution&hellip;\n","protected":false},"author":2,"featured_media":235671,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[77],"tags":[24368,18,6123,19,17,125017,133,451,125018],"class_list":["post-235670","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-astrobiology","tag-eire","tag-exoplanets","tag-ie","tag-ireland","tag-methane-atmosphere-on-trappist-1e","tag-science","tag-space","tag-webb-telescope"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/115729166795238224","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/235670","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=235670"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/235670\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/235671"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=235670"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=235670"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=235670"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}