![\"The](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/05\/The-unique-ability.png\")
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\n Modified Pass et al. (2025) Figure 2 showing an updated Cosmic Shoreline for exoplanets orbiting full convective M dwarfs. The exoplanets shift significantly along the y-axis depending on their assumed XUV history (specifically showing Pass et al. 2025 and Zahnle & Catling 2017), which changes the location of the Cosmic Shoreline. \u2014 astro-ph.IM <\/p>\n
The chemical and mass evolution of exoplanet atmospheres is shaped by their specific X-ray through ultraviolet (5 \u2013 3200 Angstroms) irradiance history. X-ray and EUV (5 \u2013 911 Angstroms) radiation largely contributes to atmospheric heating via photoionization, while far- and near-UV emission (912 \u2013 3200 Angstroms) drives photochemistry.<\/p>\n
The (uncharacterized) variance between young star spectra in this wavelength range for the same spectral type causes significant uncertainty in interpreting present-day transmission spectra of young exoplanets, directly impacting the science return of the James Webb Space Telescope and other programs.<\/p>\n
Additionally, the lack of direct X-ray through UV characterization for stars of all ages leads to large uncertainties in the high-energy irradiance history of all planetary systems, propagating into uncertainties in their chemical and mass evolution.<\/p>\n
This influences current and future observing programs, as well as the goal of the future flagship Habitable Worlds Observatory to find and characterize habitable exoplanets. There are less than a handful of young planet hosts with well-characterized X-ray through UV environments.<\/p>\n
The Hubble Space Telescope is the only observatory capable of measuring the UV spectrum and enabling the characterization of exoplanet high-energy environments. We advocate for an observing program to measure the UV, estimate the EUV, and measure the X-ray where possible and needed of all amenable young planet hosts, addressing the Space Telescope Science Institute\u2019s call for Building a Roadmap for Hubble Science into the 2030s.<\/p>\n
Keighley E. Rockcliffe (1 and 2), Allison Youngblood (2), Kevin France (3), Cynthia Froning (4), P. C. Schneider (5), Elisabeth Newton (6), David J. Wilson (3), Vighnesh Nagpal (7 and 8), Sarah Peacock (1 and 2), Seth Redfield (9), Mayumi Liz de Andrade Miyazato (10), Hans-R. M\u00fcller (6), Aylin Garc\u00eda Soto (11) ((1) University of Maryland Baltimore County, (2) NASA Goddard Space Flight Center, (3) University of Colorado, (4) Southwest Research Institute, (5) Kiel University, (6) Dartmouth College, (7) University of Chicago, (8) NSF Graduate Research Fellow, (9) Wesleyan University, (10) Colorado State University, (11) Boise State University)<\/p>\n
Xueying Li, Paco Majic, Cau\u0101 Antunes Westmann<\/p>\n
Comments: STScI \u201cBuilding a Roadmap for Hubble Science into the 2030s\u201d white paper Astrobiology, exoplanet,<\/p>\n","protected":false},"excerpt":{"rendered":"Modified Pass et al. (2025) Figure 2 showing an updated Cosmic Shoreline for exoplanets orbiting full convective M…\n","protected":false},"author":2,"featured_media":474150,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[157573,10803,153787,910,118754,187036,5621,61,60,82,2811],"class_list":["post-474149","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-astro-ph-im","tag-atmosphere","tag-biosignatures","tag-exoplanet","tag-habitable-worlds-observatory","tag-https-astrobiology-com-2026-05-imaging","tag-hubble","tag-ie","tag-ireland","tag-science","tag-spectroscopy"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/474149","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=474149"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/474149\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/474150"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=474149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=474149"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=474149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2605.28768 [astro-ph.IM] or arXiv:2605.28768v1 [astro-ph.IM] for this version)
https:\/\/doi.org\/10.48550\/arXiv.2605.28768<\/a>
Focus to learn more
Submission history
From: Keighley Rockcliffe
[v1] Wed, 27 May 2026 17:25:03 UTC (749 KB)
https:\/\/arxiv.org\/abs\/2605.28768<\/a><\/p>\n