{"id":9322,"date":"2024-08-20T00:21:07","date_gmt":"2024-08-20T04:21:07","guid":{"rendered":"https:\/\/spaceandplanetarynewswire.com\/?p=9322"},"modified":"2024-08-20T00:21:07","modified_gmt":"2024-08-20T04:21:07","slug":"a-galactic-conspiracy-disproven","status":"publish","type":"post","link":"https:\/\/spaceandplanetarynewswire.com\/?p=9322","title":{"rendered":"A Galactic Conspiracy Disproven"},"content":{"rendered":"
One of the team\u2019s Very Large Telescope images showing massive galaxies in a group. The galaxies at the centre are each about 125 billion times the mass of our sun (including their dark matter).<\/figcaption><\/figure>\n

A longstanding \u2018conspiracy\u2019 in astronomy \u2013 that stars and dark matter are interacting in inexplicable ways \u2013 has been overturned by an international team of astronomers, in a paper today in Monthly Notices of the Royal Astronomical Society<\/a><\/em> (MNRAS<\/em>). <\/p>\n

The authors are based in Australia, the UK, Austria, and Germany, and used the Very Large Telescope in Chile. <\/p>\n

The conspiracy emerged to explain a phenomenon that had puzzled astronomers for a quarter of a century. The density of matter in different galaxies appeared to be decreasing at the same rate from their centre to outer edges. This was perplexing because galaxies are diverse, with many different ages, shapes, sizes, and numbers of stars. So why would they have the same density structure?<\/p>\n

\u201cThis homogeneity suggested that dark matter and stars must somehow compensate for each other in order to produce such regular mass structures,\u201d says Dr. Caro Derkenne, the first author of the paper and an ASTRO 3D researcher from Macquarie University.<\/p>\n

Like many conspiracies, no researcher could come up with a mechanism. If dark matter and stars could interact in this way, then we would need to change our understanding of how galaxies form and evolve. But they also couldn\u2019t find an alternate reason to explain what they were seeing, until now.<\/p>\n

Derkenne and her colleagues found that the similarity in density might not be due to the galaxies themselves but in how astronomers were measuring and modelling them.<\/p>\n

The team observed 22 middle-aged galaxies (looking back some four billion years in the past due to their great distance) in extraordinary detail, using the European Southern Observatory\u2019s Very Large Telescope in Chile. It enabled them to create more complex models that better captured the diversity of galaxies in the universe. <\/p>\n

\u201cIn the past, people built simple models that had too many simplifications and assumptions,\u201d says Derkenne.<\/p>\n

\u201cGalaxies are complicated, and we have to model them with freedom or we\u2019re going to measure the wrong things. Our models ran on the OzStar supercomputer at Swinburne University, using the equivalent of about 8,000 hours of desktop computing time.\u201d<\/p>\n

Derkenne is now applying her astronomy expertise to complex data for the Australia Public Service. <\/p>\n

\u201cAstronomy sets you up really well to understand big data,\u201d she says. \u201cThe real world is messy, and we don\u2019t always have all the data. No one is there to tell you the answers or if you\u2019re wrong or right. You need to accumulate data and analyse until you find something that works.\u201d<\/p>\n

The project used MUSE (Multi Unit Spectroscopic Explorer) on the VLT to analyse the galaxies from the MAGPI survey (Middle Ages Galaxy Properties with Integral field spectroscopy). MUSE collects spectral data cubes in which every single pixel is actually a spectrum. <\/p>\n

\u201cThe MAGPI project is great example of how training workshops and collaborative space within ASTRO 3D have utilised Australia\u2019s strategic partnership with the European Southern Observatory,\u201d says ASTRO 3D Director Professor Emma Ryan-Weber. <\/p>\n

\u201cThe complex data from the ESO Very Large Telescope has not only solved a long-standing problem in Astronomy, but also enabled young scientists, such as Dr. Caro Derkenne, a platform on which to launch their careers to solve real-world problems,\u201d she says.<\/p>\n","protected":false},"excerpt":{"rendered":"

A longstanding \u2018conspiracy\u2019 in astronomy \u2013 that stars and dark matter are interacting in inexplicable ways \u2013 has been overturned by an international team of astronomers, in a paper today in Monthly Notices of the Royal Astronomical Society (MNRAS).  The authors are based in Australia, the UK, Austria, and Germany, and used the Very Large Telescope in…<\/p>\n","protected":false},"author":71,"featured_media":9323,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"fifu_image_url":"https:\/\/cdn.mos.cms.futurecdn.net\/KNGZRXySsM7quLuNUa6C4h-1200-80.jpg","fifu_image_alt":"","footnotes":""},"categories":[216],"tags":[],"class_list":["post-9322","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-discovery"],"_links":{"self":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9322","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/users\/71"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=9322"}],"version-history":[{"count":1,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9322\/revisions"}],"predecessor-version":[{"id":9324,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9322\/revisions\/9324"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/media\/9323"}],"wp:attachment":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=9322"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=9322"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=9322"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}