{"id":8747,"date":"2020-06-23T14:32:42","date_gmt":"2020-06-23T09:02:42","guid":{"rendered":"https:\/\/triumphias.com\/blog\/?p=8747"},"modified":"2020-06-23T14:32:42","modified_gmt":"2020-06-23T09:02:42","slug":"extreme-helium-star","status":"publish","type":"post","link":"https:\/\/triumphias.com\/blog\/extreme-helium-star\/","title":{"rendered":"Extreme helium star"},"content":{"rendered":"<section class=\"hero-section\" data-type=\"type-1\">\n<header class=\"entry-header\"><span style=\"color: #0000ff;\"><strong>Relevance: Prelims: Science<\/strong><\/span><\/p>\n<p><strong>Why in news?<\/strong><\/p>\n<\/header>\n<\/section>\n<div class=\"entry-content\">\n<p>\u2022 A <strong>study by the Indian Institute of Astrophysics (IIA)<\/strong> which detected the presence of singly ionised \ufb02uorine for the <strong>first time in the atmospheres of hot Extreme Helium Stars<\/strong> makes a strong case that the main formation of these objects <strong>involves a merger of a carbon-oxygen (CO) and a Helium (He)<\/strong> white dwarf.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/images.slideplayer.com\/26\/8446177\/slides\/slide_3.jpg\" alt=\"New Model Atmospheres for Hydrogen-Deficient Stars May 3 rd, 2006 ...\" \/><\/p>\n<p><b>About:<\/b><\/p>\n<p>\u2022 An extreme helium star or EHe is a low-mass supergiant that is almost devoid of hydrogen, the most common chemical element of the universe.<\/p>\n<p>\u2022 There are 21 of them detected so far in our galaxy.<\/p>\n<p>\u2022 The origin and evolution of these Hydrogen deficient objects have been shrouded in mystery.<\/p>\n<p>\u2022 Since there are no known conditions where stars devoid of hydrogen can be formed from molecular clouds, it is theorized that they are the product of the mergers of helium-core and carbon-oxygen core white dwarfs.<\/p>\n<p><b>Hydrogen-Deficient Stars:<\/b><\/p>\n<p>\u2022 Extreme helium stars form a sub-group within the broader category of hydrogen-deficient stars.<\/p>\n<p>\u2022 The latter includes cool carbon stars like R Coronae Borealis variables, helium-rich spectral class O or B stars, population I Wolf\u2013Rayet stars, AM CVn stars, white dwarfs of spectral type WC, and transition stars like PG 1159.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #0000ff;\"><strong>For more such notes, Articles, News &amp; Views Join our Telegram Channel.<\/strong><\/span><\/p>\n<p><a title=\"Telegram Link\" href=\"https:\/\/t.me\/triumphias\" target=\"_blank\"><span style=\"color: #ff0000;\"><strong>https:\/\/t.me\/triumphias<\/strong><\/span><\/a><\/p>\n<p><span style=\"color: #0000ff;\"><strong>Click the link below to see the details about the UPSC \u2013Civils courses offered by Triumph IAS.<\/strong><\/span> <span style=\"color: #ff0000;\"><strong><a style=\"color: #ff0000;\" title=\"Courses available\" href=\"https:\/\/triumphias.com\/pages-all-courses.php\">https:\/\/triumphias.com\/pages-all-courses.php<\/a><\/strong><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Relevance: Prelims: Science Why in news? \u2022 A study by the Indian Institute of Astrophysics (IIA) which detected the presence<\/p>\n","protected":false},"author":1,"featured_media":7219,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[123],"tags":[392],"class_list":["post-8747","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-current-affairs","tag-union-public-service-commission-upsc"],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/posts\/8747","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/comments?post=8747"}],"version-history":[{"count":1,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/posts\/8747\/revisions"}],"predecessor-version":[{"id":8748,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/posts\/8747\/revisions\/8748"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/media\/7219"}],"wp:attachment":[{"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/media?parent=8747"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/categories?post=8747"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/triumphias.com\/blog\/wp-json\/wp\/v2\/tags?post=8747"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}