{"id":9920,"date":"2026-05-26T08:39:04","date_gmt":"2026-05-26T12:39:04","guid":{"rendered":"https:\/\/spaceandplanetarynewswire.com\/?p=9920"},"modified":"2026-05-26T08:39:04","modified_gmt":"2026-05-26T12:39:04","slug":"astronomers-de-fog-exoplanet-atmospheres-with-new-cloud-detecting-method","status":"publish","type":"post","link":"https:\/\/spaceandplanetarynewswire.com\/?p=9920","title":{"rendered":"Astronomers De-Fog Exoplanet Atmospheres with New Cloud-Detecting Method"},"content":{"rendered":"

Discovery by Johns Hopkins researchers of daily cloud cycle on a Hot Jupiter planet provides unique window into its make-up and evolution<\/strong><\/em><\/p>\n

<\/p>\n

Sand clouds form every morning but clear up by nightfall on WASP-94A b, a well-studied gas giant in a constellation located nearly 700 light years away from Earth.<\/p>\n

The research<\/a>, which\u00a0uses data from the James Webb Space Telescope (JWST), is among the first to detect cloud cycles on a Hot Jupiter exoplanet. By isolating the clouds, researchers can more accurately measure the planet\u2019s atmosphere and provide one of the clearest pictures to date of the planet\u2019s composition \u2014 a significant advance in planetary science.<\/p>\n

\u201cI’ve been looking at exoplanets for 20 years, and general cloudiness has been a thorn in our side. We\u2019ve known for quite a while that clouds are pervasive on Hot Jupiter planets, which is annoying because it\u2019s like trying to look at the planet through a foggy window,\u201d said co-author and program PI,\u00a0David Sing<\/a>, a Bloomberg Distinguished Professor of Earth and Planetary Sciences at Johns Hopkins. \u201cNot only have we been able to clear the view, but we can finally pin down what the clouds are made out of and how they\u2019re condensing and evaporating as they move around the planet.\u201d<\/p>\n

The results are published today in the journal\u00a0Science<\/em>.<\/p>\n

To study\u00a0WASP-94A b\u00a0in the Microscopium constellation,\u00a0Sing and his team of researchers gathered data as the planet passed directly in front of its star.\u00a0Using the high-powered, space-based JWST, the researchers were able to take separate measurements of WASP-94A b’s leading edge as it started to cross in front of the star and the trailing edge\u00a0as the planet completed its transit. At the leading edge, the air flows from the night side of the planet to the day side, effectively making it the morning. Air flows from day to night at the trailing edge, making it the evening.<\/p>\n

Observations revealed that mornings and evenings on WASP-94A b\u00a0have extremely different weather patterns: mornings are riddled with clouds made of magnesium silicate, a common mineral found in rocks, while the evening has clear skies.<\/p>\n

The researchers think one of two things could be happening. Powerful winds might lift clouds high into the sky on the cooler side of the planet and then plunge downward on the hotter dayside, dragging the clouds deep into the planet\u2019s interior and effectively burying them out of sight before sunset. Alternatively, the phenomenon may be akin to morning fog burning off on Earth, but on an extreme scale. Clouds would form in the darkness of the planet\u2019s nightside. As they drift into the scorching heat of over 1,000 degrees on the day side, the chemicals that make up the clouds boil away, and the clouds simply vaporize.<\/p>\n

\u201cIt was a huge surprise. People have expected some differences, like its cooler in the morning than the evening\u2014that\u2019s something natural that we experience here on Earth,\u201d Sing said. \u201cBut what we saw was a real dichotomy between the weather on both sides of the planet, and huge differences in cloud coverage, and that changes our whole picture of the planet.\u201d<\/p>\n

Because the evenings are clear of clouds, the researchers could look to the trailing edge specifically to see what the atmosphere of the planet looked like\u2014something the Hubble telescope could not provide.<\/p>\n

\u201cWith the Hubble telescope, when we used to do this type of observation, we got an average view of the whole planet with data from the clouds and the atmosphere squished together and indistinguishable,\u201d said first author\u00a0Sagnick Mukherjee<\/a>, a postdoctoral fellow at Arizona State University who was a student at Johns Hopkins and UC Santa Cruz at the time of the research. \u201cThis approach with the JWST lets us localize our observations, which helped us see the cloud cycle.\u201d<\/p>\n

When the researchers looked at the clear evening sky, they found that WASP-94A b\u00a0was much more like Jupiter than they thought. Previously, when the clouds were averaged in, the data suggested the planet was made of hundreds of times more oxygen and carbon than Jupiter\u2014a finding that baffled researchers given it couldn\u2019t be explained by planet formation theory. The new data, however, shows WASP-94A b\u00a0has only five times the amount of oxygen and carbon.<\/p>\n

Hot Jupiter planets orbit much closer to their stars\u2014closer even than Mercury to the sun\u2014and therefore are much hotter and are exposed to more radiation. Because of their extreme environments, these planets also make good laboratories to study the chemistry and physics of cloud dynamics.<\/p>\n

Using WASP-94 Ab as a benchmark, the team looked at eight other hot gas giants and discovered the same distinctive cloud cycle on two other worlds: WASP-39 b and WASP-17 b.\u00a0Next, Sing and his team will be using data from a new large JWST program to\u00a0study\u00a0cloud cycling across a wide variety of exoplanets, including an eccentric gas giant planet in the habitable zone.<\/p>\n

– Hannah Robbins<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Discovery by Johns Hopkins researchers of daily cloud cycle on a Hot Jupiter planet provides unique window into its make-up and evolution Sand clouds form every morning but clear up by nightfall on WASP-94A b, a well-studied gas giant in a constellation located nearly 700 light years away from Earth. The research, which\u00a0uses data from…<\/p>\n","protected":false},"author":71,"featured_media":9922,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"fifu_image_url":"https:\/\/api.hub.jhu.edu\/factory\/sites\/default\/files\/styles\/soft_crop_2400\/public\/2026-05\/WASP-94A%20gas%20giant%20exoplanet%20-%20artistic%20interpretation.png","fifu_image_alt":"","footnotes":""},"categories":[207],"tags":[],"class_list":["post-9920","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research"],"_links":{"self":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9920","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/users\/71"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=9920"}],"version-history":[{"count":1,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9920\/revisions"}],"predecessor-version":[{"id":9923,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9920\/revisions\/9923"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/media\/9922"}],"wp:attachment":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=9920"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=9920"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=9920"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}