{"id":318015,"date":"2025-11-30T06:18:13","date_gmt":"2025-11-30T06:18:13","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/318015\/"},"modified":"2025-11-30T06:18:13","modified_gmt":"2025-11-30T06:18:13","slug":"water-retention-on-earth-like-planets-around-variable-stars","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/318015\/","title":{"rendered":"Water Retention on Earth-Like Planets Around Variable Stars"},"content":{"rendered":"

What can star variability\u2014changes in a star\u2019s brightness over time\u2014teach astronomers about exoplanet habitability? This is what a recent study<\/a> accepted to *The Astronomical Journal* hopes to address as a team of scientists investigated the interaction between a star\u2019s activity and exoplanetary atmospheres. This study has the potential to help astronomers better understand how star variability plays a role in finding habitable exoplanets, specifically around stars that are different from our Sun.<\/p>\n

For the study, the researchers analyzed data on nine exoplanets from nine separate stars and orbit in the habitable zone, along with whose stars exhibit elevated stellar variability. These exoplanets include TOI-1227 b<\/a> (328 light-years), HD 142415 b<\/a> (116 light-years), HD 147513 b<\/a> (42 light-years), HD 221287 b<\/a> (182 light-years), BD-08 2823 c<\/a> (135 light-years), KELT-6 c<\/a> (785 light-years), HD 238914 b<\/a> (1,694 light-years), HD 147379 b<\/a> (35 light-years), and HD 63765 b<\/a> (106 light-years). The goal of the study was to ascertain how their star\u2019s variability influenced the exoplanet\u2019s equilibrium temperature and how exoplanets orbiting within the inner edge of a star\u2019s habitable zone could retain their water. The equilibrium temperature of a planetary body is its temperature if heat transfer did not occur.<\/p>\n<\/p>\n

In the end, the researchers found that the nine stars in this study demonstrate very little influence on the equilibrium temperature of their exoplanets. Additionally, the team found that exoplanets orbiting within the inner edge of their star\u2019s habitable zone could retain water, regardless of the star\u2019s variability. <\/p>\n

The study notes in its conclusions, \u201cThis work is only a small step towards understanding the relationship between variable stars, planetary properties, and their climates. Our comparison of flux variations due to stellar variability and orbital eccentricity generally assume that the orbital period is much greater than that of the stellar variability. Additional observations of variable stars and the discovery and characterization of their planets will further enable our ability to understand how planetary climates respond to their variable host stars.\u201d<\/p>\n

The study included stars ranging in size from 0.17 to 1.25 solar masses with M-, K-, G-, and F-type stars, with M-type stars being the smallest type of stars and our Sun being a G-type star. This diversity is important to better understand the types of stars researchers could search for habitable exoplanets and comes at a time when astronomers are increasingly observing M-type stars. This is because M-type stars not only comprise the largest number of stars but also have the largest lifetimes, estimated to last up to trillions of years. For context, our Sun\u2019s lifetime is estimated to be between 10-12 billion years. <\/p>\n

Along with their vast numbers and lifetimes, M-type stars are also known for their extreme variability, specifically regarding sunspots, flares, rotational changes, and magnetic field fluctuations. As a result, their exoplanets have come into question regarding their habitability potential, since flares can strip atmospheres and ozone layers, potentially severely limiting the prospect for life. <\/p>\n<\/p>\n

Two of the most well-known examples of M-type stars with potentially habitable exoplanets whose habitability is in question due to the star\u2019s variability are Proxima Centauri<\/a> and TRAPPIST-1<\/a>, which are approximately 4.24 and 39.5 light-years from Earth, respectively. Both stars have been observed to be extremely active, including ultraviolet (UV) bursts and high radiation output. As a result, Proxima Centauri has been deemed very harsh for life to exist on the single rocky exoplanet it is known to have, while TRAPPIST-1 has seven rocky exoplanets, with one potentially being habitable despite its star\u2019s variability. <\/p>\n

What new insight into star variability and exoplanet habitability will researchers make in the coming years and decades? Only time will tell, and this is why we science!<\/p>\n

As always, keep doing science & keep looking up!<\/p>\n","protected":false},"excerpt":{"rendered":"What can star variability\u2014changes in a star\u2019s brightness over time\u2014teach astronomers about exoplanet habitability? This is what a…\n","protected":false},"author":2,"featured_media":318016,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[64,63,128,285],"class_list":{"0":"post-318015","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-au","9":"tag-australia","10":"tag-science","11":"tag-space"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/318015","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=318015"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/318015\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/318016"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=318015"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=318015"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=318015"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}