Journal<\/em><\/a> presents spectroscopic confirmation of strong gravitational lenses previously identified using Convolutional Neural Networks, developed by data scientist Dr Colin Jacobs at ASTRO 3D and Swinburne University.<\/p>\nThe work is part of the ASTRO 3D Galaxy Evolution with Lenses (AGEL) survey.<\/p>\n
\u201cOur spectroscopy allowed us to map a 3D picture of the gravitational lenses to show they are genuine and not merely chance superposition,\u201d says corresponding author Dr. Tran from the ARC Centre of Excellence for All Sky Astrophysics in 3-Dimensions (ASTRO3D) and the University of NSW (UNSW).<\/p>\n
\u201cOur goal with AGEL is to spectroscopically confirm around 100 strong gravitational lenses that can be observed from both the Northern and Southern hemispheres throughout the year,\u201d she says.<\/p>\n
The paper is the result of a collaboration spanning the globe with researchers from Australia, the United States, the United Kingdom, and Chile.<\/p>\n
The work was made possible by the development of the algorithm to look for certain digital signatures.<\/p>\n
\u201cWith that we could identify many thousands of lenses compared to just a few handfuls,\u201d says Dr. Tran.<\/p>\n
Gravitational lensing was first identified as a phenomenon by Einstein who predicted that light bends around massive objects in space in the same way that light bends going through a lens.<\/p>\n
In doing so, it greatly magnifies images of galaxies that we would not otherwise be able to see.<\/p>\n
While it has been used by astronomers to observe far away galaxies for a long time, finding these cosmic magnifying glasses in the first place has been hit and miss.<\/p>\n
\u201cThese lenses are very small so if you have fuzzy images, you’re not going to really be able to detect them,\u201d says Dr. Tran.<\/p>\n
While these lenses let us see objects that are millions of light years away more clearly, it should also let us \u2018see\u2019 invisible dark matter that makes up most of the Universe.<\/p>\n
\u201cWe know that most of the mass is dark,\u201d says Dr. Tran. \u201cWe know that mass is bending light and so if we can measure how much light is bent, we can then infer how much mass must be there.\u201d<\/p>\n
Having many more gravitational lenses at various distances will also give us a more complete image of the timeline going back almost to the Big Bang.<\/p>\n
\u201cThe more magnifying glasses you have, the better chance you can try to survey these more distant objects. Hopefully, we can better measure the demographics of very young galaxies,\u201d says Dr. Tran.<\/p>\n
\u201cThen somewhere between those really early first galaxies and us there’s a whole lot of evolution that’s happening, with tiny star forming regions that convert pristine gas into the first stars to the sun, the Milky Way.<\/p>\n
\u201cAnd so with these lenses at different distances, we can look at different points in the cosmic timeline to track essentially how things change over time, between the very first galaxies and now.\u201d<\/p>\n
Dr Tran\u2019s team spanned the globe, with each group providing different expertise.<\/p>\n
\u201cBeing able to collaborate with people, at different universities, has been so crucial, both for setting the project up in the first place, and now continuing with all of the follow-up observations,\u201d she says.<\/p>\n
Professor Stuart Wyithe of the University of Melbourne and Director of the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (Astro 3D) says each gravitational lens is unique and tells us something new.<\/p>\n
\u201cApart from being beautiful objects, gravitational lenses provide a window to studying how mass is distributed in very distant galaxies that are not observable via other techniques. By introducing ways to use these new large data sets of the sky to search for many new gravitational lenses, the team opens up the opportunity to see how galaxies get their mass,\u201d he says.<\/p>\n
Professor Karl Glazebrook of Swinburne University, and Dr Tran\u2019s Co-Science Lead on the paper, paid tribute to the work that had gone before.<\/p>\n
\u201cThis algorithm was pioneered by Dr Colin Jacobs at Swinburne. He sifted through tens of millions of galaxy images to prune the sample down to 5,000. Never did we dream that the success rate would be so high,\u201d he says.<\/p>\n
\u201cNow we are getting images of these lenses with the Hubble Space Telescope, they range from jaw-droopingly beautiful to extremely strange images that will take us considerable effort to figure out.\u201d<\/p>\n
Associate Professor Tucker Jones of UC Davis, another co-science lead on the paper, described the new sample as \u201ca giant step forward in learning how galaxies form over the history of the Universe\u201d.<\/p>\n
\u201cNormally these early galaxies look like small fuzzy blobs, but the lensing magnification allows us to see their structure with much better resolution. They are ideal targets for our most powerful telescopes to give us the best possible view of the early universe,\u201d he says.<\/p>\n
\u201cThanks to the lensing effect we can learn what these primitive galaxies look like, what they are made of, and how they interact with their surroundings.\u201d<\/p>\n
The study was conducted in collaboration with researchers from the University of New South Wales, Swinburne University of Technology, Australian National University, Curtin University, and the University of Queensland in Australia, the University of California, Davis, in the US, the University of Portsmouth, in the UK, and University of Chile.<\/p>\n
The ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) is a $40m Research Centre of Excellence funded by the Australian Research Council (ARC) and six collaborating Australian universities – The Australian National University, The University of Sydney, The University of Melbourne, Swinburne University of Technology, The University of Western Australia, and Curtin University.<\/p>\n
Contacts:<\/u><\/strong><\/p>\n Bill Condie (Media Contact, Science in Public)<\/strong><\/p>\nPh: +61 450 952 365 E: bill@scienceinpublic.com.au<\/p>\n
Kim-Vy Tran (Media Contact, ASTRO 3D)<\/strong><\/p>\nPh: +61 405 865 890 E: kim-vy.tran@unsw.edu.au<\/p>\n<\/div><\/div><\/div><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":272,"featured_media":32185,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,21,2,7,8,10],"tags":[276,88,32,107],"coauthors":[210],"class_list":["post-32183","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-galaxy-evolution","category-melbourne","category-news","category-science","category-swinburne","category-unsw","tag-agel-survey","tag-galactic-evolution","tag-galaxies","tag-galaxy-evolution"],"acf":[],"yoast_head":"\n
Dozens of newly discovered gravitational lenses could reveal ancient galaxies and the nature of dark matter - ASTRO 3D<\/title>\n \n \n \n \n \n \n \n \n \n \n\t \n\t \n\t \n \n \n \n\t \n\t \n\t \n