{"id":146444,"date":"2014-02-08T17:30:03","date_gmt":"2014-02-08T19:30:03","guid":{"rendered":"http:\/\/revistapesquisa.fapesp.br\/?p=146444"},"modified":"2014-04-08T17:33:40","modified_gmt":"2014-04-08T20:33:40","slug":"yardstick-universe","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/yardstick-universe\/","title":{"rendered":"A yardstick for the universe"},"content":{"rendered":"<div id=\"attachment_146445\" style=\"max-width: 300px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-146445\" alt=\"In this artistic rendering, each circle, with a radius of 500 million light-years, represents a region that has a greater concentration of galaxies\" src=\"http:\/\/revistapesquisa.fapesp.br\/wp-content\/uploads\/2014\/04\/Tecno_Universo.jpg\" width=\"290\" height=\"186\" srcset=\"https:\/\/revistapesquisa.fapesp.br\/wp-content\/uploads\/2014\/04\/Tecno_Universo.jpg 290w, https:\/\/revistapesquisa.fapesp.br\/wp-content\/uploads\/2014\/04\/Tecno_Universo-120x77.jpg 120w, https:\/\/revistapesquisa.fapesp.br\/wp-content\/uploads\/2014\/04\/Tecno_Universo-250x160.jpg 250w\" sizes=\"auto, (max-width: 290px) 100vw, 290px\" \/><p class=\"wp-caption-text\"><span class=\"media-credits-inline\">Zosia Rostomian\/LBNL <\/span>In this artistic rendering, each circle, with a radius of 500 million light-years, represents a region that has a greater concentration of galaxies<span class=\"media-credits\">Zosia Rostomian\/LBNL <\/span><\/p><\/div>\n<p>Astronomers have determined distances between clusters of galaxies with record precision, better establishing the properties of dark energy\u2014a poorly understood form of energy\u2014in empty space, which is accelerating the universe&#8217;s expansion since its birth in the Big Bang.\u00a0 In its first 300,000 years, the universe was filled with a hot, dense gas, made of atomic nuclei, free electrons and radiation.\u00a0 The expansion of the universe caused this gas to cool and become rarefied, forming stars and galaxies.\u00a0 However, the waves that propagated in the primordial gas left vestiges in the distribution of galaxies in the Cosmos.\u00a0 Galaxies tend to accumulate in regions that were once the crests of these waves called baryon acoustic oscillations.\u00a0 The regular spacing of these crests creates a natural cosmic yardstick, and the increase in the distance between the crests can be used to detect the influence of dark energy.\u00a0 In today&#8217;s universe, this spacing is about 500 million light-years.\u00a0 During a meeting of the American Astronomical Association, on January 8, 2014, researchers from the Baryon Oscillation Spectroscopic Survey (Boss) reported measurements of baryon acoustic oscillations with a precision of 1%.\u00a0 The study analyzed more than 1 million galaxies, spread over a region 6 billion light-years across.\u00a0 Boss is one of the four astronomical survey projects being undertaken as part of Sloan Digital Sky Survey 3 (SDSS-III), in which Brazilian groups are involved.\u00a0 The project uses a unique telescope, located in New Mexico, United States, which analyzes the light from thousands of galaxies simultaneously.<\/p>\n","protected":false},"excerpt":{"rendered":"Distances between galaxy clusters throw light on dark energy","protected":false},"author":475,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[168],"tags":[205,235],"coauthors":[785],"class_list":["post-146444","post","type-post","status-publish","format-standard","hentry","category-technoscience","tag-astronomy","tag-physics"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/146444","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/users\/475"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=146444"}],"version-history":[{"count":0,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/146444\/revisions"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=146444"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=146444"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=146444"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=146444"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}