{"id":19497,"date":"2016-01-16T22:10:32","date_gmt":"2016-01-16T14:10:32","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/alien-megastructure-revisited-oddly-dimming-star-poses-new-mystery\/"},"modified":"2016-01-16T22:10:32","modified_gmt":"2016-01-16T14:10:32","slug":"alien-megastructure-revisited-oddly-dimming-star-poses-new-mystery","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/alien-megastructure-revisited-oddly-dimming-star-poses-new-mystery\/","title":{"rendered":"\u2018Alien megastructure\u2019 revisited: Oddly dimming star poses new mystery"},"content":{"rendered":"<figure id=\"attachment_216679\" aria-describedby=\"caption-attachment-216679\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img fetchpriority=\"high\" decoding=\"async\" class=\"size-full-width wp-image-216679\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2015\/12\/151209-dyson-630x427.jpg\" alt=\"Dyson sphere megastructure\" width=\"630\" height=\"427\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2015\/12\/151209-dyson-630x427.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2015\/12\/151209-dyson-768x521.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2015\/12\/151209-dyson.jpg 1024w\" sizes=\"(max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-216679\" class=\"wp-caption-text\">An artist\u2019s representation shows a crumbling megastructure known as a Dyson sphere orbiting KIC 8462852. (Credit: Danielle Futselaar \/ SETI International)<\/figcaption><\/figure>\n<p>He\u2019s not saying it\u2019s aliens&nbsp;\u2013 but an astronomer has raised new questions about KIC 8462852, the strange star that stirred up a debate about&nbsp;\u201calien megastructures\u201d months ago.<\/p>\n<p>In a paper submitted to Astrophysical Journal Letters, Lousiana State University\u2019s Bradley Schaefer reviews archival photographic plates that show KIC 8462852&nbsp;at various times going back to 1890. He reports that the star, which&nbsp;is 1,500 light-years away in the constellation Cygnus, faded by about 20 percent between the 1890s and the 1980s.<\/p>\n<p>\u201cThis century-long dimming is completely unprecedented for any F-type main sequence star,\u201d Schaefer writes.<\/p>\n<p>KIC 8462852\u2019s dimming was already worthy of note, due to observations by NASA\u2019s Kepler space telescope that revealed&nbsp;unusual episodes during which the star faded by as much as 20 percent. That led Penn State astronomer Jason&nbsp;Wright to observe that such a pattern was consistent with what you\u2019d expect if aliens were building an energy-generating megastructure known as a \u201cDyson sphere\u201d around the star.<\/p>\n<p><iframe title=\"Building a Dyson Sphere\" src=\"https:\/\/www.youtube.com\/embed\/GrM3f7Bil5A?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>Wright\u2019s speculation touched off a flurry of reports, as well as close reviews of data from the Allen Telescope Array and NASA\u2019s Spitzer Space Telescope. Those reviews found nothing out of the ordinary. Most astronomers came around to the view that KIC 8462852\u2019s dimming was the result of cometary swarms that swept past the star, temporarily obscuring its light.<\/p>\n<p>Schaefer, however, argues that the century-long dimming and the more recent anomalous episodes were most likely to have been caused by \u201cone physical mechanism.\u201d<\/p>\n<p>\u201cThis one mechanism does not appear as any isolated catastrophic event in the last century, but rather must be some ongoing process with continuous effects,\u201d he writes.<\/p>\n<p>So what could it be? Aliens are still one of the least likely explanations, but a more sedate debate over KIC 8462852 is likely to continue for quite some time. Even before Schaefer\u2019s paper came to light, Centauri Dreams\u2019 Paul Gilster raised the possibility&nbsp;that \u201cwe\u2019re seeing a natural phenomenon we can\u2019t yet identify.\u201d<\/p>\n<figure id=\"attachment_223381\" aria-describedby=\"caption-attachment-223381\" style=\"width: 630px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full-width wp-image-223381\" src=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2016\/01\/160116-wow-630x356.jpg\" alt=\"Wow Signal\" width=\"630\" height=\"356\" srcset=\"https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2016\/01\/160116-wow-630x356.jpg 630w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2016\/01\/160116-wow-768x434.jpg 768w, https:\/\/cdn.geekwire.com\/wp-content\/uploads\/2016\/01\/160116-wow.jpg 800w\" sizes=\"(max-width: 630px) 100vw, 630px\"><figcaption data-nosnippet=\"\" id=\"caption-attachment-223381\" class=\"wp-caption-text\">Astronomer Jerry Ehman scribbled the word \u201cWow!\u201d next to red-circled radio readings in 1977. (Credit: Ohio State University Radio Observatory \/ North American Astrophysical Observatory)<\/figcaption><\/figure>\n<h4><strong>\u2018Wow\u2019 Signal explained?<\/strong><\/h4>\n<p>Speaking of astronomical anomalies and comets, another study&nbsp;to be published by the Washington Academy of Sciences suggests that one of the best-known anomalies in SETI lore could have been caused by a pair of comets.<\/p>\n<p>The anomalous 72-second radio emission, now renowned as the \u201cWow\u201d Signal, was picked up in 1977 by the Ohio State University Radio Observatory (a.k.a. the Big Ear). The signal was so out of the ordinary that astronomer Jerry Ehman wrote the word \u201cWow!\u201d beside the readings.<\/p>\n<p>Astronomers looked for a natural explanation and came up short. But the new study, written&nbsp;by St. Petersburg College\u2019s Antonio Paris and Evan Davies of the Explorers Club, says the signal could have been generated by cometary clouds of hydrogen.<\/p>\n<p>Paris and Davies point to two comets in particular, known as 266P\/Christensen and P\/2008 Y2 (Gibbs).<\/p>\n<p><iframe loading=\"lazy\" title=\"The Wow! Signal\" src=\"https:\/\/www.youtube.com\/embed\/a0rByLgRdLM?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>Astronomers didn\u2019t know those comets existed back in 1977, but after their discovery in 2006 and 2008, they could trace their orbital paths backward.&nbsp;It turns out the comets were passing through the area being monitored by the now-defunct Big Ear when the \u201cWow\u201d Signal was detected.<\/p>\n<p>Paris and Davies note that the comets are on track to return to the \u201cWow\u201d Signal\u2019s celestial neighborhood in 2017 and 2018.<\/p>\n<p>\u201cDuring this period, the astronomical community will have an opportunity to direct radio telescopes toward this phenomenon, analyze the hydrogen spectra of these two comets, and test the authors\u2019 hypothesis,\u201d they write.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>An artist\u2019s representation shows a crumbling megastructure known as a Dyson sphere orbiting KIC 8462852. (Credit: Danielle Futselaar \/ SETI International) He\u2019s not saying it\u2019s aliens&nbsp;\u2013 but an astronomer has raised new questions about KIC 8462852, the strange star that stirred up a debate about&nbsp;\u201calien megastructures\u201d months ago. In a paper submitted to Astrophysical Journal [&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":[4666,4409,1661,2826,5286,3754,5588],"class_list":["post-19497","post","type-post","status-publish","format-standard","hentry","category-news","tag-alien-megastructure","tag-aliens","tag-astronomy","tag-kepler","tag-kic-8462852","tag-seti","tag-wow-signal"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/19497"}],"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=19497"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/19497\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=19497"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=19497"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=19497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}