[{"command":"openDialog","selector":"#drupal-modal","settings":null,"data":"\u003Cdiv id=\u0022republish_modal_form\u0022\u003E\u003Cform class=\u0022modal-form-example-modal-form ecl-form\u0022 data-drupal-selector=\u0022modal-form-example-modal-form\u0022 action=\u0022\/en\/article\/modal\/7046\u0022 method=\u0022post\u0022 id=\u0022modal-form-example-modal-form\u0022 accept-charset=\u0022UTF-8\u0022\u003E\u003Cp\u003EHorizon articles can be republished for free under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence.\u003C\/p\u003E\n \u003Cp\u003EYou must give appropriate credit. We ask you to do this by:\u003Cbr \/\u003E\n 1) Using the original journalist\u0027s byline\u003Cbr \/\u003E\n 2) Linking back to our original story\u003Cbr \/\u003E\n 3) Using the following text in the footer: This article was originally published in \u003Ca href=\u0027#\u0027\u003EHorizon, the EU Research and Innovation magazine\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003ESee our full republication guidelines \u003Ca href=\u0027\/horizon-magazine\/republish-our-stories\u0027\u003Ehere\u003C\/a\u003E\u003C\/p\u003E\n \u003Cp\u003EHTML for this article, including the attribution and page view counter, is below:\u003C\/p\u003E\u003Cdiv class=\u0022js-form-item form-item js-form-type-textarea form-item-body-content js-form-item-body-content ecl-form-group ecl-form-group--text-area form-no-label ecl-u-mv-m\u0022\u003E\n \n\u003Cdiv\u003E\n \u003Ctextarea data-drupal-selector=\u0022edit-body-content\u0022 aria-describedby=\u0022edit-body-content--description\u0022 id=\u0022edit-body-content\u0022 name=\u0022body_content\u0022 rows=\u00225\u0022 cols=\u002260\u0022 class=\u0022form-textarea ecl-text-area\u0022\u003E\u003Ch2\u003EAstronomers reveal first-ever image of a black hole\u003C\/h2\u003E\u003Cp\u003EThe image shows the event horizon \u2013 the gravitational point of no return beyond which nothing, not even light, can escape \u2013 around the supermassive black hole in a nearby galaxy.\u003C\/p\u003E\u003Cp\u003EIt is the first time in history that such an image has been produced and was the result of a global collaboration of scientists working on the \u003Ca href=\u0022https:\/\/eventhorizontelescope.org\/\u0022\u003EEvent Horizon Telescope\u003C\/a\u003E (EHT) project.\u003C\/p\u003E\u003Cp\u003E\u2018History books will be divided into the time before the image and after the image,\u2019 said Dr Michael Kramer from the Max Planck Institute for Radio Astronomy in Germany, one of the principal investigators on \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/rcn\/192284\/factsheet\/en\u0022 target=\u0022_blank\u0022 rel=\u0022noopener noreferrer\u0022\u003EBlackHoleCam\u003C\/a\u003E, the European contribution to the EHT. \u2018It is the first time that this has been possible, and it\u2019s been long in the making.\u2019\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EMessier 87\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe image shows the shadow of the event horizon around the supermassive black hole inside Messier 87 (M87), an elliptical galaxy located 53 million light-years from Earth. Seeing this event horizon is no mean feat; the black hole itself, while 6.5 billion times more massive than our Sun, is still incredibly small at this distance.\u003C\/p\u003E\u003Cp\u003EThat is one of the reasons such an image has never been taken before. No telescope alone possesses the observational power to observe the supermassive black holes believed to be at the centre of all galaxies. Instead, the EHT project combined the power of eight large radio telescopes around the world, from the South Pole to Spain, to create an Earth-sized virtual super telescope.\u003C\/p\u003E\u003Cp\u003E\u2018We observed with (eight telescopes) simultaneously, so that as Earth rotates, there are three or four that are always pointing to the (black hole),\u2019 said Dr Luciano Rezzolla from Goethe University Frankfurt in Germany, another principal investigator on BlackHoleCam. \u2018We have collected (information) and built an image that we believe is consistent with what we would expect from a black hole.\u2019\u003C\/p\u003E\u003Cp\u003E\u003Cblockquote class=\u0022tw-text-center tw-text-blue tw-font-bold tw-text-2xl lg:tw-w-1\/2 tw-border-2 tw-border-blue tw-p-12 tw-my-8 lg:tw-m-12 lg:tw--ml-16 tw-float-left\u0022\u003E\n \u003Cspan class=\u0022tw-text-5xl tw-rotate-180\u0022\u003E\u201c\u003C\/span\u003E\n \u003Cp class=\u0022tw-font-serif tw-italic\u0022\u003E\u2018Of course we would have loved to prove Einstein wrong, but everything we see fits perfectly the prediction that is given by general relativity.\u2019\u003C\/p\u003E\n \u003Cfooter\u003E\n \u003Ccite class=\u0022tw-not-italic tw-font-normal tw-text-sm tw-text-black\u0022\u003EDr Heino Falcke, Radboud University Nijmegen, Netherlands\u003C\/cite\u003E\n \u003C\/footer\u003E\n\u003C\/blockquote\u003E\n\u003C\/p\u003E\u003Cp\u003EObservations of the black hole at the heart of M87 were taken over a window of 10 days in April 2017, when fortuitously good weather allowed the telescopes to continuously observe the object. Using a technique called very-long-baseline interferometry (VLBI), the teams then combined the observations of the telescopes to give the final image.\u003C\/p\u003E\u003Cp\u003EBut so much data was collected \u2013 4 petabytes, or 4 million gigabytes \u2013 that it could not be digitally transferred. It had to be physically transported by sea and air before image processing could take place. It took the astronomers until summer 2018 to actually put the final image together.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ERelativity\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe existence of black holes was first proposed following Albert Einstein\u2019s general theory of relativity in 1915. It was suggested that if an object\u2019s mass reached astonishingly high levels, it would collapse in on itself into a singularity, a point in space and time where gravity is so intense that the known laws of physics break down.\u003C\/p\u003E\u003Cp\u003ESince then we have found indirect evidence for black holes. We have seen regions of super-heated material swirling around suspected black holes, known as quasars, and we have seen stars \u003Ca href=\u0022https:\/\/www.theguardian.com\/science\/2018\/jul\/26\/star-spotted-speeding-near-milky-way-black-hole-for-first-time\u0022 target=\u0022_blank\u0022 rel=\u0022noopener noreferrer\u0022\u003Eorbiting the black hole\u003C\/a\u003E believed to be at the centre of our own galaxy. We have also detected gravitational waves \u2013 ripples in space-time formed by two black holes merging. Never before, however, have we actually seen a black hole.\u003C\/p\u003E\u003Cp\u003EAnd the image of M87\u2019s black hole matches our predictions for what it should look like. The shadow of the black hole is proof that its gravity is so intense that it is bending light itself, a prediction made thanks to general relativity. We can also see that the boundary between the interior and exterior of the black hole \u2013 the event horizon \u2013 actually exists, with a ring of photons of light surrounding it.\u003C\/p\u003E\u003Cp\u003E\u2018Of course we would have loved to prove Einstein wrong, but everything we see fits perfectly the prediction that is given by general relativity,\u2019 said Dr Heino Falcke from Radboud University Nijmegen in the Netherlands, also a principal investigator on BlackHoleCam. \u2018It\u2019s confirmation that one of the most fundamental predictions (of general relativity) has passed the test.\u2019\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ESagittarius A*\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EWhile the researchers focused on M87 for this image, the overall EHT project also has plans to try and produce an image of the black hole at the Milky Way\u2019s galactic centre, called Sagittarius A*.\u003C\/p\u003E\u003Cp\u003EUsing the same VLBI method, the team has already taken observations of this object, and will hope to produce an image in the coming year or so. While it is considerably closer than M87\u2019s black hole at just 25,000 light-years away, it is also about 1,000 times smaller at 4 million solar masses, presenting its own unique challenges.\u003C\/p\u003E\u003Cp\u003E\u2018At the same time we took data from M87 we also took data from our galactic centre,\u2019 said Dr Kramer. \u2018For now we have concentrated efforts on M87, and once that is out, we will focus all our attention on Sagittarius A*.\u2019\u003C\/p\u003E\u003Cp\u003EThe scientists are also hopeful that this discovery will usher in a new era of black hole observations. The technique they used pushed the limits of modern technology, but it proved it is very much possible. By combining multiple telescopes around the world, essentially turning Earth into one giant telescope, such fascinating objects in the universe become possible to see.\u003C\/p\u003E\u003Cp\u003EThe major limitation of this method is the size of Earth \u2013 we cannot build a virtual telescope on our planet larger than the planet itself. So if we want to observe black holes in other galaxies, we may have to use telescopes in space. Using three telescopes in Earth orbit, for example, it could be possible to see even more black holes in the coming decades.\u003C\/p\u003E\u003Cp\u003E\u2018The only way to see more of these black holes is to have a telescope that\u2019s larger than Earth,\u2019 said Dr Falcke. \u2018And for that we need to go to space.\u2019\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EHow scientists turned Earth into a giant telescope\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\n \n\n\n\u003Col class=\u0022ecl-timeline\u0022data-ecl-auto-init=\u0022Timeline\u0022 data-ecl-timeline\u003E\u003Cli\n class=\u0022ecl-timeline__item\u0022\n \u003E\u003Cdiv class=\u0022ecl-timeline__tooltip\u0022\u003E\u003Cdiv class=\u0022ecl-timeline__tooltip-arrow\u0022\u003E\u003C\/div\u003E\u003Cdiv class=\u0022ecl-timeline__label\u0022\u003EStep 5\u003C\/div\u003E\u003Cdiv class=\u0022ecl-timeline__title\u0022\u003EPainting by numbers\u003C\/div\u003E\u003Cdiv class=\u0022ecl-timeline__content\u0022\u003E\u003Cp\u003ELaying out the data on a virtual canvas, researchers essentially painted the image by numbers to produce the world\u2019s first ever picture of a black hole.\u003C\/p\u003E\u003Cimg src=\u0022\/sites\/default\/files\/hm\/black-hole-star.jpg\u0022 alt=\u0022\u0022 \/\u003E\nImage credit - NASA; S. Gezari, The Johns Hopkins University; and J. Guillochon, University of California, Santa Cruz\n\u003C\/div\u003E\u003C\/div\u003E\u003C\/li\u003E\u003C\/ol\u003E\n\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThe research in this article was funded by the EU\u2019s European Research Council. If you liked this article, please consider sharing it on social media.\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cdiv class=\u0022moreinfoblock\u0022\u003E\n \u003Ch3\u003EBackground support\u003C\/h3\u003E\n \u003Cp\u003EBehind the mission to capture an image of a black hole is a global network of radio telescopes \u2013 state-of-the-art instruments that need to be able to operate at their full capacity. Maintenance and upgrades are done regularly on the two European telescopes \u2013 APEX and the IRAM 30-metre array at Pico Veleta \u2013 partly supported by the \u003Ca href=\u0022https:\/\/cordis.europa.eu\/project\/rcn\/207426\/en\u0022\u003ERadioNet\u003C\/a\u003E project, which also trains networks of radio astronomers in their use. To turn the network of telescopes in to a single observatory, they work together using a technique called very-long-baseline interferometry. This is a specialist area of knowledge for which the scientists are supported by Europe\u2019s Joint Institute for VLBI.\u003C\/p\u003E\n\u003C\/div\u003E\n\u003C\/p\u003E\u003C\/textarea\u003E\n\u003C\/div\u003E\n\n \u003Cdiv id=\u0022edit-body-content--description\u0022 class=\u0022ecl-help-block description\u0022\u003E\n Please copy the above code and embed it onto your website to republish.\n \u003C\/div\u003E\n \u003C\/div\u003E\n\u003Cinput autocomplete=\u0022off\u0022 data-drupal-selector=\u0022form-i0prwykpd8zq-6gqf0zndqxas-gxomk-zpdkucmpdjs\u0022 type=\u0022hidden\u0022 name=\u0022form_build_id\u0022 value=\u0022form-I0PrWykPd8zq_6gQF0zNdQXAs_gxOmk-ZPDkuCMPDjs\u0022 \/\u003E\n\u003Cinput data-drupal-selector=\u0022edit-modal-form-example-modal-form\u0022 type=\u0022hidden\u0022 name=\u0022form_id\u0022 value=\u0022modal_form_example_modal_form\u0022 \/\u003E\n\u003C\/form\u003E\n\u003C\/div\u003E","dialogOptions":{"width":"800","modal":true,"title":"Republish this content"}}]