Here\u2019s what you\u2019ll learn when you read this story:<\/p>\n
About one billion years after the Big Bang, the universe experienced a period known as the “epoch of reionization” where the neutral hydrogen atoms that filled the universe became ionized from the UV light of the very first stars.<\/p>\n
Now a new study wants to understand the conditions of the universe right at the tail-end of the \u201ccosmic dark ages\u201d before this reionization kicked off.<\/p>\n
Using a decade of data from the Murchison Widefield Array telescope located in Western Australia, researchers determined that the reionization did not have a \u201ccold start,\u201d and that heating, probably due to black holes and stellar remnants, likely began some 800 million years after the Big Bang.<\/p>\n
Everyone is familiar with our universe\u2019s explosive beginnings\u2014things got really hot and really dense until there was a Big Bang<\/a>. However, the sequel<\/a> to this explosive preamble is decidedly different in tone. After the Big Bang, the universe rapidly cooled and expanded until finally\u2014400,000 years later\u2014protons and electrons merged to form hydrogen atoms.<\/p>\n As Live Science<\/a> notes, what followed is known as the \u201ccosmic dark age\u201d when the universe was filled with this neutral hydrogen<\/a> for about one billion years until the arrival of the first stars and galaxies. Once these primordial stars emitted UV light that stripped hydrogen atoms of their electrons, the cosmos entered the \u201cEpoch of Reionization<\/a>\u201d and the universe began to resemble what we picture today. This is the universe\u2019s toddler days, so to speak.<\/p>\n However, unlike an obsessive parent documenting every milestone of their drooling progeny, astrophysicists don’t have such a wealth of evidence\u2014instead, they have to go looking for it. For example, we don\u2019t really know what the conditions of the universe were when it began to transition from the \u201ccosmic dark age.\u201d While some theories suggest reionization<\/a> developed from a \u201ccold start,\u201d a new study from an international team of scientists provides evidence the universe was actually heating up prior to this major milestone in the universe\u2019s development. The results of the study were published in The Astrophysical Journal<\/a>.<\/p>\n \u201cAs the universe evolved, the gas between galaxies expands and cools, so we would expect it to be very, very cold,\u201d Curtin University\u2019s Cathryn Trott, lead author of the study, said in a press statement<\/a>. “Our measurements show that it is at least heated by a certain amount. Not by a lot, but it tells us that very cold reionization is ruled out.\u201d<\/p>\n Glimpsing something that far in the past isn\u2019t easy, and Trott and her team utilized the Murchison Widefield Array telescope located in Western Australia to facilitate the challenging observation. Operating at 70\u2013300 MHz, the telescope<\/a> is purpose-built to detect that aforementioned neutral hydrogen emission from the \u201cepoch of reionization.\u201d Even so, the authors needed to perform a lot of subtraction in order to isolate what they were looking for from the cosmic noise<\/a> of nearby stars, galaxies, and even Earth\u2019s atmosphere.<\/p>\n Because the team was able to create this filtered data\u2014as well as having the benefit of ten years worth of it\u2014they could make a discovery by omission. If the universe was cold at this time, it would emit a certain kind of signal, but the researchers found no evidence of it, suggesting that at least some warming was going on. The theory is that x-rays from early black holes and stellar remnants drove this heating around 800 million years after the Big Bang. They haven\u2019t found the tell-tale signal of that heating yet, but the researchers say that it\u2019s likely only a matter of time.<\/p>\n \u201cAll these existing techniques will help us find what\u2019s missing,\u201d Curtin University\u2019s Ridhima Nunhokee, a co-author of the study, said in a press statement. \u201cThe signal is definitely buried in there. It’s just improving on our data, and getting more data, cleaner data, to reach it.\u201d<\/p>\n [galleryCarousel id=’9e9354e9-d0c6-426e-ba21-7d41e95744de’ mediaId=’4e41e3f9-da64-411e-893d-af8a56c7b137′ display=’carousel’ align=’center’ size=’medium’ share=’true’ expand=” captions=’true’ suppress-title=’false’ hasProducts=’false’][\/galleryCarousel]<\/p>\n You Might Also Like<\/p>\n","protected":false},"excerpt":{"rendered":"Here\u2019s what you\u2019ll learn when you read this story: About one billion years after the Big Bang, the…\n","protected":false},"author":2,"featured_media":248870,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[32],"tags":[129980,135915,135917,79,135916],"class_list":{"0":"post-248869","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-hydrogen-atoms","9":"tag-murchison-widefield-array","10":"tag-reionization","11":"tag-science","12":"tag-stellar-remnants"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/248869","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=248869"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/248869\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/248870"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=248869"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=248869"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=248869"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}