{"id":57199,"date":"2017-10-16T16:01:29","date_gmt":"2017-10-16T14:01:29","guid":{"rendered":"https:\/\/uniavisen.dk\/neutronstjerner\/"},"modified":"2017-10-17T13:38:17","modified_gmt":"2017-10-17T11:38:17","slug":"ucph-scientists-contributed-to-neutron-stars-discovery","status":"publish","type":"post","link":"https:\/\/uniavisen.dk\/en\/ucph-scientists-contributed-to-neutron-stars-discovery\/","title":{"rendered":"UCPH scientists contributed to sensational neutron stars discovery"},"content":{"rendered":"<p>It is no more than two years ago that scientists first observed gravitational\u00a0 <secret text=\"According to the Niels Bohr Institute gravitational waves can be described as gravity released from its source and rushing through space at the speed of light. When it reaches its destination it changes space-time a bit, and the biggest gravitational waves can be measured by gravitational wave detectors\">waves<\/secret>\u2013 i.e. ripples in space-time. This was at the <secret text=\"The Laser Interferometer Gravitational-Wave Observatory (LIGO)\">LIGO<\/secret>\u00a0observatory\u00a0 in the United States, and the discovery led to this year&#8217;s Nobel Prize in physics.<\/p>\n<p>Now Danish scientists have helped take the next step, according to a series of press releases from the Niels Bohr Institute at the University of Copenhagen (UCPH).<\/p>\n<p>They have, for the first time, used a combination of gravitational wave measurements and observations of electromagnetic radiation with telescopes to describe a clash between two neutron stars merging and setting off a <em>kilonova<\/em>, a giant explosion which set off a powerful burst of gamma rays in <secret text=\"The Washington Post in its excellent coverage of the scientific event likens this to someone slamming their fist down on a tube of toothpaste with an opening in each end.\">two opposite  directions<\/secret>.<\/p>\n<p>Scientists from the Dark Cosmology Center (DARK) at UCPH had hoped to contribute to the discovery.<\/p>\n<p>\u00bbThis is exactly what we wanted to do, but we had not expected it to happen so fast. We thought we would have had to wait for several years. With this, it all came together,\u00ab says Professor Jens Hjorth, head of DARK, according to the Institute&#8217;s Danish press release.<\/p>\n<h3>Radioactive fireball<\/h3>\n<p>That the research environment was well-prepared for the discovery of the neutron star collision is also evident in the fact that Jens Hjorth told news site\u00a0<a href=\"http:\/\/videnskab.dk\/naturvidenskab\/rygter-om-tyngdeboelger-fra-kolliderende-neutronstjerner\">Videnskab.dk in 2016<\/a> that he hoped to be able to observe a gamma burst after a gravitational wave.<\/p>\n<p>The discovery of the kilonova took place after the gravitational wave monitors in Virgo (Italy) and LIGO recorded minor fluctuations in space-time on 17th August, 2017. Shortly afterwards, the predicted gamma burst of electromagnetic radiation hit the space observatories Fermi and Integral.<\/p>\n<p>By linking the measurements from the different instruments, astronomers around the world could search in a demarcated area of \u200b\u200bthe universe for the origin of the waves and the radiation.<\/p>\n<p>It took 11 hours. Then a research team which included UCPH Professor Enrico Ramirez-Ruiz found a bright spot in space, a radioactive fireball that was expanding at one fifth the speed of light.<\/p>\n<p>In the fusion of the two neutron stars, matter corresponding to three and five per cent of the mass of the Sun was flung out into space.<\/p>\n<p>After one and a half days, the radius of the ball was\u00a0<secret text=\"In comparison, the Earth is 150 million kilometres from the Sun\">eight billion kilometres<\/secret>.<\/p>\n<h3>Astronomers used to be able to see it, now they can both see and hear it<\/h3>\n<p>According to PhD student Jonatan Selsing of UCPH, the use of gravitational observations means that astronomers in effect have gained an extra sense:<\/p>\n<p>\u00bbImagine you&#8217;re out for a walk in the forest. You hear something rustling on the forest floor, then you know approximately where to look for an animal. With a little luck you will be able to see it. This is what it is like in astronomy now, because we &#8211; with gravitational wave detectors &#8211; can &#8216;listen&#8217; to the universe and find out where to look closer.\u00ab<\/p>\n<h3>Solves heavy elements puzzle<\/h3>\n<p>A neutron star is what is left over when a dead\u00a0 <secret text=\"Between 10 and 29 times the mass of the Sun according to Wikipedia. Bigger stars end up as black holes.\">giant star<\/secret> explodes into a supernova; it is a small, hot, heavy core, just 20 kilometers in diameter, of hard, compressed neutrons \u2013 a matchbox sized neutron star weighs three billion tons, corresponding to a 800 by <secret text=\"According to Wikipedia.\">800 metres<\/secret> cube of the Earth.<\/p>\n<p>The neutron star collision has already made it into a series of scientific articles with new discoveries.<\/p>\n<p>These include studies of the radiation from the kilonova, showing that inside the hot matter a number of heavy elements are created. Some of the neutrons from the two stars decayed to protons and electrons in the process, accumulating thereby into new atoms, including heavy substances like cesium and tellurium. This can be seen in the spectrum of light emitted by the kilonova, an analysis that PhD student Jonathan Selsing contributed to.<\/p>\n<p>He says that each morning after the kilonova detection at 7am, he would receive data from observatories in Chile, analysing it with software, he developed himself.<\/p>\n<p>\u00bbI was lucky to have the right skill-set at the right time,\u00ab he says.<\/p>\n<p>The formation of heavy elements has been one of the big enigmas of science, because at the Big Bang only hydrogen, helium and lithium were created. And the lighter elements \u2013 up to iron \u2013 are formed by fusion processes in the interior of stars.<\/p>\n<p>Astrophysics have put forward the theory that heavy elements such as gold and platinum are formed in the collision between neutron stars, and the new discovery of the star collision seems to support the idea.<\/p>\n<p>The researchers at the Niels Bohr Institute will continue to analyze their data and possibly identify more elements created in the explosion.<br \/>\n<!-- end of module 1 --><\/p>\n","protected":false},"excerpt":{"rendered":"<p>By combining measurements of gravitational waves and observations of light, the scientists have discovered and described a clash between two neutron stars. Analyses of light from the explosion &#8211; called a kilonova &#8211; show the creation of heavy elements, solving an older scientific problem.<\/p>\n","protected":false},"author":7,"featured_media":57186,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[46],"tags":[861,863,862,401,220],"class_list":["post-57199","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science","tag-astronomi-en","tag-astronomy","tag-dark-en","tag-niels-bohr-institute","tag-niels-bohr-institutet-en","expression-news_article"],"acf":[],"aioseo_notices":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.4 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>UCPH scientists contributed to sensational neutron stars discovery<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/uniavisen.dk\/en\/ucph-scientists-contributed-to-neutron-stars-discovery\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"UCPH scientists contributed to sensational neutron stars discovery\" \/>\n<meta property=\"og:description\" content=\"By combining measurements of gravitational waves and observations of light, the scientists have discovered and described a clash between two neutron stars. Analyses of light from the explosion - called a kilonova - show the creation of heavy elements, solving an older scientific problem.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/uniavisen.dk\/en\/ucph-scientists-contributed-to-neutron-stars-discovery\/\" \/>\n<meta property=\"og:site_name\" content=\"University Post\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/uniavis\" \/>\n<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/christoffer.zieler\" \/>\n<meta property=\"article:published_time\" content=\"2017-10-16T14:01:29+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2017-10-17T11:38:17+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/uniavisen.dk\/wp-content\/uploads\/2017\/10\/nasaneutronstjerner.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1912\" \/>\n\t<meta property=\"og:image:height\" content=\"880\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Christoffer Zieler\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@Uniavisen\" \/>\n<meta name=\"twitter:site\" content=\"@Uniavisen\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Christoffer Zieler\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/\"},\"author\":{\"name\":\"Christoffer Zieler\",\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/#\\\/schema\\\/person\\\/a96cc389f544930451424dd312b34b8c\"},\"headline\":\"UCPH scientists contributed to sensational neutron stars discovery\",\"datePublished\":\"2017-10-16T14:01:29+00:00\",\"dateModified\":\"2017-10-17T11:38:17+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/\"},\"wordCount\":906,\"commentCount\":0,\"image\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/uniavisen.dk\\\/wp-content\\\/uploads\\\/2017\\\/10\\\/nasaneutronstjerner.jpg\",\"keywords\":[\"Astronomi\",\"Astronomy\",\"DARK\",\"Niels Bohr Institute\",\"Niels Bohr Institutet\"],\"articleSection\":[\"Science\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/\",\"url\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/\",\"name\":\"UCPH scientists contributed to sensational neutron stars discovery\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/uniavisen.dk\\\/wp-content\\\/uploads\\\/2017\\\/10\\\/nasaneutronstjerner.jpg\",\"datePublished\":\"2017-10-16T14:01:29+00:00\",\"dateModified\":\"2017-10-17T11:38:17+00:00\",\"author\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/#\\\/schema\\\/person\\\/a96cc389f544930451424dd312b34b8c\"},\"breadcrumb\":{\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/uniavisen.dk\\\/en\\\/ucph-scientists-contributed-to-neutron-stars-discovery\\\/#primaryimage\",\"url\":\"https:\\\/\\\/uniavisen.dk\\\/wp-content\\\/uploads\\\/2017\\\/10\\\/nasaneutronstjerner.jpg\",\"contentUrl\":\"https:\\\/\\\/uniavisen.dk\\\/wp-content\\\/uploads\\\/2017\\\/10\\\/nasaneutronstjerner.jpg\",\"width\":1912,\"height\":880,\"caption\":\"Screendump fra en tre \u00e5r gammel videosimulation af, hvad der sker, n\u00e5r to netronstjerner kolliderer. 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Now scientists \u2013 including some from the University of Copenhagen \u2013 have documented a clash between two neutron stars."},{"acf_fc_layout":"Standfirst","subject":"Astrophysics","text":"By combining measurements of gravitational waves and observations of light, the scientists have discovered and described a clash between two neutron stars. Analyses of light from the explosion - called a kilonova - show the creation of heavy elements, solving an older scientific problem.","use_post_excerpt":false},{"acf_fc_layout":"Byline","is_author":true,"contributors":false},{"acf_fc_layout":"Content","content":"<p>It is no more than two years ago that scientists first observed gravitational\u00a0 <secret text=\"According to the Niels Bohr Institute gravitational waves can be described as gravity released from its source and rushing through space at the speed of light. When it reaches its destination it changes space-time a bit, and the biggest gravitational waves can be measured by gravitational wave detectors\">waves<\/secret>\u2013 i.e. ripples in space-time. This was at the <secret text=\"The Laser Interferometer Gravitational-Wave Observatory (LIGO)\">LIGO<\/secret>\u00a0observatory\u00a0 in the United States, and the discovery led to this year&#8217;s Nobel Prize in physics.<\/p>\n<p>Now Danish scientists have helped take the next step, according to a series of press releases from the Niels Bohr Institute at the University of Copenhagen (UCPH).<\/p>\n<p>They have, for the first time, used a combination of gravitational wave measurements and observations of electromagnetic radiation with telescopes to describe a clash between two neutron stars merging and setting off a <em>kilonova<\/em>, a giant explosion which set off a powerful burst of gamma rays in <secret text=\"The Washington Post in its excellent coverage of the scientific event likens this to someone slamming their fist down on a tube of toothpaste with an opening in each end.\">two opposite  directions<\/secret>.<\/p>\n<p>Scientists from the Dark Cosmology Center (DARK) at UCPH had hoped to contribute to the discovery.<\/p>\n<p>\u00bbThis is exactly what we wanted to do, but we had not expected it to happen so fast. We thought we would have had to wait for several years. With this, it all came together,\u00ab says Professor Jens Hjorth, head of DARK, according to the Institute&#8217;s Danish press release.<\/p>\n<h3>Radioactive fireball<\/h3>\n<p>That the research environment was well-prepared for the discovery of the neutron star collision is also evident in the fact that Jens Hjorth told news site\u00a0<a href=\"http:\/\/videnskab.dk\/naturvidenskab\/rygter-om-tyngdeboelger-fra-kolliderende-neutronstjerner\">Videnskab.dk in 2016<\/a> that he hoped to be able to observe a gamma burst after a gravitational wave.<\/p>\n<p>The discovery of the kilonova took place after the gravitational wave monitors in Virgo (Italy) and LIGO recorded minor fluctuations in space-time on 17th August, 2017. Shortly afterwards, the predicted gamma burst of electromagnetic radiation hit the space observatories Fermi and Integral.<\/p>\n<p>By linking the measurements from the different instruments, astronomers around the world could search in a demarcated area of \u200b\u200bthe universe for the origin of the waves and the radiation.<\/p>\n<p>It took 11 hours. Then a research team which included UCPH Professor Enrico Ramirez-Ruiz found a bright spot in space, a radioactive fireball that was expanding at one fifth the speed of light.<\/p>\n<p>In the fusion of the two neutron stars, matter corresponding to three and five per cent of the mass of the Sun was flung out into space.<\/p>\n<p>After one and a half days, the radius of the ball was\u00a0<secret text=\"In comparison, the Earth is 150 million kilometres from the Sun\">eight billion kilometres<\/secret>.<\/p>\n<h3>Astronomers used to be able to see it, now they can both see and hear it<\/h3>\n<p>According to PhD student Jonatan Selsing of UCPH, the use of gravitational observations means that astronomers in effect have gained an extra sense:<\/p>\n<p>\u00bbImagine you&#8217;re out for a walk in the forest. You hear something rustling on the forest floor, then you know approximately where to look for an animal. With a little luck you will be able to see it. This is what it is like in astronomy now, because we &#8211; with gravitational wave detectors &#8211; can &#8216;listen&#8217; to the universe and find out where to look closer.\u00ab<\/p>\n<h3>Solves heavy elements puzzle<\/h3>\n<p>A neutron star is what is left over when a dead\u00a0 <secret text=\"Between 10 and 29 times the mass of the Sun according to Wikipedia. Bigger stars end up as black holes.\">giant star<\/secret> explodes into a supernova; it is a small, hot, heavy core, just 20 kilometers in diameter, of hard, compressed neutrons \u2013 a matchbox sized neutron star weighs three billion tons, corresponding to a 800 by <secret text=\"According to Wikipedia.\">800 metres<\/secret> cube of the Earth.<\/p>\n<p>The neutron star collision has already made it into a series of scientific articles with new discoveries.<\/p>\n<p>These include studies of the radiation from the kilonova, showing that inside the hot matter a number of heavy elements are created. Some of the neutrons from the two stars decayed to protons and electrons in the process, accumulating thereby into new atoms, including heavy substances like cesium and tellurium. This can be seen in the spectrum of light emitted by the kilonova, an analysis that PhD student Jonathan Selsing contributed to.<\/p>\n<p>He says that each morning after the kilonova detection at 7am, he would receive data from observatories in Chile, analysing it with software, he developed himself.<\/p>\n<p>\u00bbI was lucky to have the right skill-set at the right time,\u00ab he says.<\/p>\n<p>The formation of heavy elements has been one of the big enigmas of science, because at the Big Bang only hydrogen, helium and lithium were created. And the lighter elements \u2013 up to iron \u2013 are formed by fusion processes in the interior of stars.<\/p>\n<p>Astrophysics have put forward the theory that heavy elements such as gold and platinum are formed in the collision between neutron stars, and the new discovery of the star collision seems to support the idea.<\/p>\n<p>The researchers at the Niels Bohr Institute will continue to analyze their data and possibly identify more elements created in the explosion.<\/p>\n"},{"acf_fc_layout":"Newsletter","lang_select":"Dansk","identifier":"Newsletter","headline":"Receive a weekly newsletter in your inbox","button_text":"Tilmeld nu","class":""},{"acf_fc_layout":"ArticleEnd"},{"acf_fc_layout":"OtherStories","headline":"","hand_picked_posts":false,"references":false,"category":false,"theme":false,"number_of_posts":"4","style":"default"}],"expression":{"term_id":15,"name":"News Article","slug":"news_article","term_group":0,"term_taxonomy_id":15,"taxonomy":"expression","description":"","parent":0,"count":11491,"filter":"raw"},"enable_comments":true,"align_content":"alignleft","feature_color":""},"taxonomyData":{"category":[{"term_id":46,"name":"Science","slug":"science","term_group":0,"term_taxonomy_id":46,"taxonomy":"category","description":"","parent":0,"count":831,"filter":"raw"}],"post_tag":[{"term_id":861,"name":"Astronomi","slug":"astronomi-en","term_group":0,"term_taxonomy_id":861,"taxonomy":"post_tag","description":"","parent":0,"count":2,"filter":"raw"},{"term_id":863,"name":"Astronomy","slug":"astronomy","term_group":0,"term_taxonomy_id":863,"taxonomy":"post_tag","description":"","parent":0,"count":2,"filter":"raw"},{"term_id":862,"name":"DARK","slug":"dark-en","term_group":0,"term_taxonomy_id":862,"taxonomy":"post_tag","description":"","parent":0,"count":1,"filter":"raw"},{"term_id":401,"name":"Niels Bohr Institute","slug":"niels-bohr-institute","term_group":0,"term_taxonomy_id":401,"taxonomy":"post_tag","description":"","parent":0,"count":17,"filter":"raw"},{"term_id":220,"name":"Niels Bohr Institutet","slug":"niels-bohr-institutet-en","term_group":0,"term_taxonomy_id":220,"taxonomy":"post_tag","description":"","parent":0,"count":7,"filter":"raw"}],"post_format":[],"expression":[{"term_id":15,"name":"News Article","slug":"news_article","term_group":0,"term_taxonomy_id":15,"taxonomy":"expression","description":"","parent":0,"count":11491,"filter":"raw"}],"translation_priority":[]},"featured_media_url":"https:\/\/uniavisen.dk\/wp-content\/uploads\/2017\/10\/nasaneutronstjerner-1280x589.jpg","_links":{"self":[{"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/posts\/57199","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/comments?post=57199"}],"version-history":[{"count":5,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/posts\/57199\/revisions"}],"predecessor-version":[{"id":57228,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/posts\/57199\/revisions\/57228"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/media\/57186"}],"wp:attachment":[{"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/media?parent=57199"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/categories?post=57199"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/uniavisen.dk\/en\/wp-json\/wp\/v2\/tags?post=57199"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}