{"id":18186,"date":"2019-01-10T19:31:32","date_gmt":"2019-01-10T11:31:32","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/could-barnards-star-harbor-an-icy-home-for-life-astronomers-weigh-the-options\/"},"modified":"2019-01-10T19:31:32","modified_gmt":"2019-01-10T11:31:32","slug":"could-barnards-star-harbor-an-icy-home-for-life-astronomers-weigh-the-options","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/could-barnards-star-harbor-an-icy-home-for-life-astronomers-weigh-the-options\/","title":{"rendered":"Could Barnard\u2019s Star harbor an icy home for life? Astronomers weigh the options"},"content":{"rendered":"<figure id=\"attachment_473224\" aria-describedby=\"caption-attachment-473224\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img fetchpriority=\"high\" decoding=\"async\" class=\"size-full-width wp-image-473224\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2019\/01\/190110-dwarf-630x473.jpg\" alt=\"Red dwarf star with planets\" width=\"630\" height=\"473\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2019\/01\/190110-dwarf-630x473.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2019\/01\/190110-dwarf-768x576.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2019\/01\/190110-dwarf.jpg 946w\" sizes=\"(max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-473224\" class=\"wp-caption-text\">An artist\u2019s conception shows three planets around a red dwarf star. (NASA \/ JPL-Caltech Illustration)<\/figcaption><\/figure>\n<p>Where\u2019s the nearest exoplanet with conditions that are right for life? Over the past couple of years, astrobiologists have talked up Proxima Centauri b, which is sitting just 4.2 light-years away.<\/p>\n<p>But Villanova University astrophysicist Edward Guinan favors a world that\u2019s just a bit farther out, at least in astronomical terms. It\u2019s Barnard\u2019s Star b, a super-Earth that orbits Barnard\u2019s Star, 6 light-years from our solar system.<\/p>\n<p>Both planets have red dwarfs as their parent stars, but their environments could hardly be more different.<\/p>\n<p>Proxima b is thought to bask in an Earthlike range of temperatures, but it\u2019s also bathed in 650 times more X-rays and 130 times more ultraviolet radiation than Earth experiences, Guinan said today during a news briefing at the American Astronomical Society\u2019s winter meeting in Seattle.<\/p>\n<p>Because of its wider orbit, Barnard b gets only 2 percent as much illumination as Earth does. Its surface temperature is thought to be somewhere in the neighborhood of 270 degrees below zero Fahrenheit (-170 degrees Celsius).<\/p>\n<p>But on the bright side, it gets half as much X-ray exposure as Earth does, and 35 percent as much UV radiation.<\/p>\n<p>\u201cYou can avoid those high radiation levels&nbsp;\u2014 if you don\u2019t mind the cold,\u201d Guinan said.<\/p>\n<p>The key question about Barnard b has to do with exactly what kind of planet it is.<\/p>\n<p><iframe title=\"ESOcast 184 Light: Super-Earth Orbiting Barnard\u2019s Star (4K UHD)\" src=\"https:\/\/www.youtube.com\/embed\/UpIxRR99Veo?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen=\"\" data-ratio=\"0.5625\" data-width=\"800\" data-height=\"450\" style=\"display: block; margin: 0px; width: 800px; height: 450px;\"><\/iframe><\/p>\n<p>Based on 18 years\u2019 worth of archived spectral data, Guinan and his colleagues estimate that the exoplanet is at least 3.2 times as massive as Earth, in a middle range between our own planet and Neptune. The mass could be significantly greater, depending on how Barnard b\u2019s orbit is oriented with respect to Earth.<\/p>\n<p>If Barnard b is a rocky super-Earth with an icy shell,&nbsp;there\u2019s a chance that life could exist beneath the ice.<\/p>\n<p>\u201cGeothermal heating could support \u2018life zones\u2019 under its surface, akin to subsurface lakes found in Antarctica,\u201d Guinan said in a news release. \u201cWe note that the surface temperature on Jupiter\u2019s icy moon Europa is similar to Barnard b but, because of tidal heating, Europa probably has liquid oceans under its icy surface.\u201d<\/p>\n<p>If Barnard b is a massive, gassy mini-Neptune, the chances for life decrease dramatically.<\/p>\n<p>Guinan and his colleagues hope the planet is on the smaller side of the size spectrum. And he said the planet is \u201con the hairy edge of being imageable\u201d with instruments like the SPHERE adaptive-optics system on the European Southern Observatory\u2019s Very Large Telescope.<\/p>\n<p>\u201cIf they see it, it is probably not good,\u201d Guinan said. That would suggest Barnard b is on the bigger side of the size spectrum, and more like Neptune than like Earth.<\/p>\n<p>The outlook for directly imaging Barnard b would be better when next-generation space observatories like NASA\u2019s James Webb Space Telescope, WFIRST telescope and the proposed planet-hunting LUVOIR telescope swing into operation, over the next decade or two. Even future ground-based telescopes, such as the Thirty Meter Telescope that\u2019s planned for construction on Hawaii, could spot Barnard b if they\u2019re equipped with the right kind of adaptive optics.<\/p>\n<p>An Earth-sized planet that\u2019s orbiting in the habitable zone around Barnard\u2019s Star \u201cis one of the easiest targets for TMT,\u201d said Thayne Currie, who works on the Subaru Coronagraphic Extreme Adaptive Optics system&nbsp;that\u2019s attached to the Subaru Telescope in Hawaii.<\/p>\n<p>Spectral analysis of the light reflected by the planet could tell astronomers whether it\u2019s a super-Earth or a mini-Neptune. But even if it\u2019s habitable, we\u2019re not likely to build ice hotels on Barnard b anytime soon. Even if you could travel at the velocity of the fastest-ever spacecraft, it\u2019d take about 17,500 years to get there.<\/p>\n<p><em>Check out the poster presentation for \u201cX-Ray, UV, Optical Irradiances and Age of Barnard\u2019s Star\u2019s New Super Earth Planet \u2013 \u2018Can Life Find a Way\u2019 on such a Cold Planet?\u201d The authors are Guinan, Villanova astrophysicist Scott Engle and Ignasi Ribas, director of the Institute of Space Studies of Catalonia and the Institute of Space Sciences.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>An artist\u2019s conception shows three planets around a red dwarf star. (NASA \/ JPL-Caltech Illustration) Where\u2019s the nearest exoplanet with conditions that are right for life? Over the past couple of years, astrobiologists have talked up Proxima Centauri b, which is sitting just 4.2 light-years away. But Villanova University astrophysicist Edward Guinan favors a world [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[4393,1874,1661,5083,559],"class_list":["post-18186","post","type-post","status-publish","format-standard","hentry","category-news","tag-aas","tag-astrobiology","tag-astronomy","tag-barnards-star","tag-exoplanets"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/18186"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=18186"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/18186\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=18186"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=18186"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=18186"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}