{"id":316,"date":"2015-01-29T20:59:28","date_gmt":"2015-01-30T01:59:28","guid":{"rendered":"http:\/\/sites.williams.edu\/scientephic\/?p=316"},"modified":"2015-01-30T17:59:49","modified_gmt":"2015-01-30T22:59:49","slug":"ask-an-astronomy-student-what-is-energy","status":"publish","type":"post","link":"https:\/\/sites.williams.edu\/scientephic\/news\/ask-an-astronomy-student-what-is-energy\/","title":{"rendered":"Ask an Astronomy Student: What is Energy?"},"content":{"rendered":"

This is the third installment in \u00a0our “Ask A Science Student” series. For the previous responses,\u00a0see chemistry<\/a> and physics<\/a>.<\/p>\n

Ask a Science Student, Part 3: Astronomy<\/strong><\/p>\n

By Marcus Hughes ’18<\/em><\/p>\n

Astronomy deals with a tremendous scale of energy, from the Cosmic Microwave Background – the\u00a02.7 kelvin echo\u00a0left from the Big Bang – to\u00a0hyper-luminous\u00a0quasars – compact centers of galaxies related to black holes\u00a0that\u00a0release\u00a04 trillion times as much energy as our\u00a0Sun.\u00a0Astronomy\u00a0even\u00a0has not yet understood types of energy like dark energy,\u00a0a repulsive energy causing\u00a0the universe to expand faster, literally changing the fate of the universe.\u00a0When most people think of energy in astronomy, they think of stars, but dark energy makes up 70% of the total mass-energy in the universe.\u00a0At its simplest, energy is just the capacity to do work; i.e. the capacity for a force to displace an object.<\/p>\n

<\/p>\n

For example,\u00a013.6 billion years ago the Big Bang released tremendous amounts of energy, causing the universe to begin expanding in all directions.\u00a0About 4.6 billion years ago, our sun formed from clouds of hydrogen cooling and coalescing. When\u00a0the cloud\u00a0reached a\u00a0high enough\u00a0density, hydrogen fusion began.\u00a0By combining hydrogen atoms to form helium, excess energy was and still is released to prevent the exterior parts of the sun from collapsing\u00a0in on the center\u00a0due to its own gravity.<\/p>\n

This continuous struggle of collapse versus fusion defines most of the star’s lifecyle\u00a0during what astronomers call the main sequence. Eventually, the sun won’t be able to release enough energy through hydrogen fusion\u00a0and will begin collapsing. After more energy exchanges,\u00a0the sun will expand to several times its original size, becoming a red giant. Finally, the sun will lose its outer layers to form a planetary nebula, leaving a hot burning center to eventually cool off billions of years into the future. This is just one example of the many energy exchanges in astronomy.<\/p>\n

Image source:\u00a0http:\/\/irfu.cea.fr\/en\/Phocea\/Vie_des_labos\/Ast\/ast.php?id_ast=2996<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

This is the third installment in \u00a0our “Ask A Science Student” series. For the previous responses,\u00a0see chemistry and physics. Ask a Science Student, Part 3: Astronomy By Marcus Hughes ’18 Astronomy deals with a tremendous scale of energy, from the Cosmic Microwave Background – the\u00a02.7 kelvin echo\u00a0left from the Big Bang – to\u00a0hyper-luminous\u00a0quasars – compact … Continue reading Ask an Astronomy Student: What is Energy?<\/span> →<\/span><\/a><\/p>\n","protected":false},"author":922,"featured_media":323,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"ngg_post_thumbnail":0,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[39900,21878],"tags":[],"class_list":["post-316","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-astronomy","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/posts\/316","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/users\/922"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/comments?post=316"}],"version-history":[{"count":5,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/posts\/316\/revisions"}],"predecessor-version":[{"id":324,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/posts\/316\/revisions\/324"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/media\/323"}],"wp:attachment":[{"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/media?parent=316"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/categories?post=316"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sites.williams.edu\/scientephic\/wp-json\/wp\/v2\/tags?post=316"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}