News: Centre Onsalahttp://www.chalmers.se/sv/nyheterNews related to Chalmers University of TechnologySat, 16 Oct 2021 07:52:47 +0200http://www.chalmers.se/sv/nyheterhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/SKAO-Chalmers-agreement.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/SKAO-Chalmers-agreement.aspxLeading the world's largest radio telescope project<p><b>​Chalmers will lead Sweden’s participation in the project to build the world's largest radio telescopes. At a ceremony held in Manchester and Gothenburg on September 30, 2021, a new agreement was signed between Chalmers and the intergovernmental organisation SKA Observatory. The agreement covers the next two years, giving time for Sweden to establish a formal membership in the international organisation.</b></p>​<span style="background-color:initial">The international SKA Observatory (SKAO) was established in early 2021. Its two vast telescopes, located at remote sites in South Africa and Australia, will together become one of this century’s most important scientific facilities. </span><div><br /><span style="background-color:initial"></span><div>“With the new agreement in place, Chalmers has a new, official role as leading Swedish interests in the construction of the SKA Observatory's giant telescopes. Funding for Swedish participation in the construction project is already secured, thanks to support from the Swedish Research Council and Vinnova”, says Lars Börjesson, board member of the SKAO.</div> <div><br /></div> <div>The two SKA telescopes are made up of many individual antennas, each sensitive to invisible radio waves from space. In total, 197 dish antennas will be placed in South Africa, forming a telescope for shorter wavelengths. Over 130 000 smaller antennas will make up the other telescope, located in Australia, sensitive to longer wavelength. </div> <div><br /></div> <div>Both will be able to map radio waves from the cosmos with unprecedented sensitivity. <span style="background-color:initial">The telescopes will investigate the mysteries of dark energy, dark matter, and cosmic magnetism, study how galaxies have</span><span style="background-color:initial"> </span><span style="background-color:initial">evolved</span><span style="background-color:initial">, test Einstein’s theories, and search for clues to the origins of life.</span></div> <div><br /></div> <div>“Scientists in Sweden and all over the world want to use the SKA telescopes to ask some of our biggest questions about the universe. <span style="background-color:initial">Membership in the SKA Observatory makes it possible for Swedish science and technology to be involved in building of these unique telescopes. It also ensures access to scientific data, and the chance to make exciting discoveries in astronomy and physics</span><span style="background-color:initial">”, explains John Conway.</span></div> <div><strong><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/ska_signing1_bengtsson_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br />Openings for industry</strong></div> <div><br /></div> <div>The new agreement means that Swedish companies are now eligible to tender for industrial contracts on equal terms as the SKAO’s current member countries. </div> <div><br /></div> <div>“This is a great opportunity for Sweden’s high-tech industries to get involved in a challenging and extremely exciting project”, says John Conway, director of Onsala Space Observatory and professor of radio astronomy at Chalmers.</div> <div><br /></div> <div>When the SKA telescopes are operational, they will generate data in quantities that make what today counts as &quot;big data&quot; look small. </div> <div><br /></div> <div>The new agreement also means a green light for the establishment in Sweden of one of SKAO's regional data processing centres. These centres are designed to handle the flood of data from SKA’s telescopes and supply final data products to astronomers.</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/ska_signing3_zoom_72dpi_340x193.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /><br /><br /></div> <div><strong>Swedish tech opening new windows on the universe</strong></div> <div><br /></div> <div>The documents signed on 30 September 2021 by Stefan Bengtsson, Chalmers' president, and Philip Diamond, Director General of the SKA Observatory, give Chalmers the responsibility of representing Sweden in the project during the next two years. During that time, national processes will continue towards establishing Sweden as a member country of SKAO.</div> <div><br /></div> <div>“Sweden has been involved in the SKA project since the start. It’s wonderful to welcome Chalmers and Onsala Space Observatory in this new official role, just as building work is starting in South Africa and in Australia”, says Philip Diamond.</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/ska_signing2_chalmers_72dpi_340x201.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /><span style="background-color:initial">“Before long, the SKA telescopes will begin to show us a whole new universe, giving scientists all over the world new discoveries and new challenges. When that happens, we can be proud of having supplied key Swedish technology to the project, technology with its roots right here at Chalmers and at Onsala Space Observatory”, says Stefan Bengtsson.</span><br /></div> <div> </div> <div><br /></div> <div><strong>More about Sweden’s role in the SKA project</strong></div> <div><br /></div> <div>Onsala Space Observatory represented Swedish interests in the SKA design process between 2012 and 2021 as a member of the SKA Organization. </div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/SKA-Mid_wide_angle_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br />Chalmers and Swedish companies have made important contributions to the design and prototyping of the SKA telescopes, with the support of Big Science Sweden and working together with colleagues in Canada, France, India, Spain and South Africa.</div> <div><br /></div> <div><ul><li>The telescopes’ physically largest radio receivers, known as Band 1, have been designed and prototyped at Onsala Space Observatory. After a competitive procurement process, they will be manufactured by a Swedish company and a complete set delivered to SKAO's telescope in South Africa. </li> <li><span style="background-color:initial">Innovative low-noise amplifiers for Band 1 and for two other SKA receiver bands will supplied by the Gothenburg company Low Noise Factory, making use of the Chalmers MyFab clean room facility for the fabrication of core components.</span><br /></li> <li><span style="background-color:initial">The digital sampler design for the telescope in South Africa is now being finalised by the Gothenburg company Qamcom Research &amp; Technology AB. T</span>he digital samplers will also be manufactured by a Swedish company after a competitive procurement process.<br /></li></ul></div> <div><br /></div> <div>Swedish involvement in the SKAO is also opening new opportunities in data storage, machine learning and artificial intelligence. </div> <div><br /></div> <div>“At Onsala Space Observatory we’ve already started exploring these opportunities, working together Chalmers Fraunhofer Centre for Industrial Mathematics. That was demonstrated recently by an outstanding Swedish team performance in a recent international data challenge, applying machine learning to simulated SKA data”, says John Conway.</div> <div><br /></div> <div><strong>More about the SKA Observatory and Onsala Space Observatory</strong></div> <div><br /></div> <div><span style="background-color:initial">The SKAO, formally known as the SKA Observatory, is a global collaboration of Member States whose mission is to build and operate cutting-edge radio telescopes to transform our understanding of the Universe, and deliver benefits to society through global collaboration and innovation.</span><br /></div> <div><div><br /></div> <div>Headquartered in the UK, its two telescope arrays will be constructed in Australia and South Africa and be the two most advanced radio telescope networks on Earth. A later expansion is envisioned in both countries and other African partner countries. Together with other state-of-the-art research facilities, the SKAO’s telescopes will explore the unknown frontiers of science and deepen our understanding of key processes, including the formation and evolution of galaxies, fundamental physics in extreme environments and the origins of life. Through the development of innovative technologies and its contribution to addressing societal challenges, the SKAO will play its part to address the United Nations’ Sustainable Development Goals and deliver significant benefits across its membership and beyond.</div> <div><br /></div> <div>The SKAO recognises and acknowledges the Indigenous peoples and cultures that have traditionally lived on the lands on which the SKAO facilities are located.</div></div> <div><br /></div> <div><span style="background-color:initial">Onsala Space Observatory is Sweden's national infrastructure for radio astronomy, hosted by the Department of Space, Earth and Environment at Chalmers University of Technology. The observatory provides researchers with equipment for the study of both the distant universe and of our earth. At Onsala, 45 km south of Gothenburg, the observatory operates four radio telescopes and a station in the international telescope Lofar. The SKA project is one of several international projects that the observatory participates in. Onsala Space Observatory receives funding from the Swedish Research Council and from the Swedish National Mapping Agency to support its activities in astronomy and geoscience, respectively.</span><br /></div> <div><span style="background-color:initial"><br /></span></div> <div><strong>Contacts</strong></div> <div><br /></div> <div>Robert Cumming, communicator, Onsala Space Observatory, Chalmers, tel: +46 31-772 5500 or +46 70 493 3114, robert.cumming@chalmers.se.</div> <div><br /></div> <div>John Conway, professor and infrastructure director, Onsala Space Observatory, Chalmers, +46 31-772 5500, john.conway@chalmers.se</div> <div><br /></div> <div><strong><em>Images</em></strong></div> <div><strong><em><br /></em></strong></div> <div><em>A (top) - Nighttime composite image of the SKA combining all elements in South Africa and Australia. Credit: SKAO, ICRAR, SARAO / Acknowledgment: The GLEAM view of the centre of the Milky Way, in radio colour. Credit: Natasha Hurley-Walker (Curtin / ICRAR) and the GLEAM Team.</em></div> <div><em>Image credit: SKAO</em></div> <div><em></em></div> <div><em><br /></em></div> <div><div><em>B - At a ceremony on 30 September 2021, Stefan Bengtsson, president of Chalmers (foreground) and </em><em style="background-color:initial">Philip Diamond director general of the SKAO </em><em style="background-color:initial">(right, on screen</em><em style="background-color:initial">) </em><em style="background-color:initial">signed the new agreement between the SKAO and Chalmers. </em></div> <div><em style="background-color:initial">Image credit: Chalmers/R. Cumming</em></div> <div><em> </em></div> <div><div><em>C - The signing ceremony was held at the SKAO headquarters at Jodrell Bank, UK, and at Chalmers, with guests participating digitally. This screenshot shows Stefan Bengtsson and the Chalmers event (upper right) and professor Catherine Cesarsky, chair of the SKAO Board (below).</em></div> <div><em>Image credit: SKAO</em></div> <div><em><br /></em></div> <div><em></em></div></div> <div><em>D - The signing ceremony on 30 September 2021 in Gothenburg was attended by John Conway, director of Onsala Space Observatory, Lars Börjesson, board member of the SKAO, Stefan Bengtsson, president of Chalmers and Eva Wirström, division head for Onsala Space Observatory. </em></div> <div><em>Image credit: Chalmers/R. Cumming</em></div></div> <div><br /></div> <div><div><em>E –  This image shows an artist’s impression of the array of 197 dish antennas in South Africa. Of these 64 antennas (right half of image) are already in place in the form of the MeerKAT telescope. </em></div> <div><em>Image credit: SKAO</em></div></div> <div> </div> <div><br /></div></div> ​Thu, 07 Oct 2021 08:00:00 +0200https://www.chalmers.se/en/areas-of-advance/ict/news/Pages/Can-automated-fact-checkers-clean-up-the-mess.aspxhttps://www.chalmers.se/en/areas-of-advance/ict/news/Pages/Can-automated-fact-checkers-clean-up-the-mess.aspxCan automated fact checkers clean up the mess?<p><b>​The dream of free dissemination of knowledge seems to be stranded in a swamp of tangled truth. Fake news proliferates. Digital echo chambers confirm biases. Even basic facts seem hard to be agreed upon. Is there hope in the battle to clean up this mess?  </b></p>​Yes! Within the research area of information and communications technology (ICT) a lot of effort is made to find software solutions. As part of the<span style="background-color:initial"> Act Sustainable week, starting 15th of November, t</span><span style="background-color:initial">h</span><span style="background-color:initial">e ICT Area of Advance </span><span style="background-color:initial">invites you to a morning session with focus on automated fact-checking.​ </span><div><br /><span style="background-color:initial"></span><div><div> <h3 class="chalmersElement-H3">AGENDA 18 November</h3> <div><div></div> <div><div><b>09:45 Introduction </b></div> <div><b>Erik Ström</b>, Director, Information and Communications Technology Area of Advance</div> <div><b>10:00 Looking for the truth in the post-truth era</b></div> <div><b>Ivan Koychev,</b> University of Sofia, Bulgaria. He will give a brief overview of how to automatically find the claims and facts in the text and how further to look for their confirmation or refutation.</div> <div><b>10:30 Computational Fact Checking for Textual Claims</b></div> <div><b>Paolo Papotti,</b> Associate Professor, EURECOM, France. He will cover the opportunities and limitations of computational fact checking and its role in fighting misinformation. He will also give examples from the &quot;infodemic&quot; associated with the COVID-19 pandemic.</div> <div><b>11:00 Pause</b></div> <div><b>11:10 Panel discussion</b></div> <div>Moderator <b>Graham Kemp</b>, professor, Department of Computer Science and Engineering, Chalmers together with an invited panel.​ More info to come!</div> <div><b>12:00 The end​</b></div></div> <div><b><br /></b></div> <div></div></div> <div>Welcome to learn more about how to sort out some of the tangle!​</div> <div><br /></div> <div><a href="https://www.actsustainable.se/thursday21" target="_blank" title="link to the Act Sustainable website"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Read more and register here</a></div> <div><a href="https://www.actsustainable.se/thursday21" target="_blank" title="link to the Act Sustainable website"></a><a href="https://www.actsustainable.se/" target="_blank" title="Link to start page Act Sustainable website"><img class="ms-asset-icon ms-rtePosition-4" src="/_layouts/images/icgen.gif" alt="" />Read more about the Act Sustainable week​</a>​<br /></div></div></div> <div><br /></div></div>Fri, 01 Oct 2021 00:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Galaxies-inner-secrets-LOFAR.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Galaxies-inner-secrets-LOFAR.aspxGalaxies’ inner secrets revealed in detail<p><b>​Astronomers at Chalmers are part of the international team behind new, uniquely detailed images from the gigantic radio telescope Lofar which reveal the inner workings of galaxies. The images are the culmination of almost a decade of work in combining data from a network of over 70 000 antennas spread over nine European countries, among them Sweden.</b></p><div><span style="background-color:initial"><strong>Revealing a hidden universe in high definition</strong></span><br /></div> <div><br /></div> <div>The universe is awash with electromagnetic radiation, of which visible light comprises just the tiniest slice. From short-wavelength gamma rays and X-rays, to long-wavelength microwave and radio waves, each part of the light spectrum reveals something unique about the universe. </div> <div><br /></div> <div>The Lofar network captures images at FM radio frequencies that, unlike shorter wavelength sources like visible light, are not blocked by the clouds of dust and gas that can cover astronomical objects. Regions of space that seem dark to our eyes, actually burn brightly in radio waves – allowing astronomers to peer into star-forming regions or into the heart of galaxies themselves.</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/I3_HerculesA_Timmerman_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br />The new images, made possible because of the international nature of the collaboration, push the boundaries of what we know about galaxies and super-massive black holes. A special issue of the scientific journal <em>Astronomy &amp; Astrophysics</em> is dedicated to new research papers describing these images and the scientific results.</div> <div><br /></div> <div>The international team of scientists, led by Leah Morabito at Durham University, UK, includes Chalmers astronomers John Conway and Eskil Varenius, and Deepika Venkattu, Ph.D. student at the Department of Astronomy, Stockholm University. </div> <div><br /></div> <div><strong>Better resolution by working together</strong></div> <div><br /></div> <div>The images reveal the inner workings of nearby and distant galaxies at a resolution 20 times sharper than typical Lofar images. This was made possible by the unique way the team made use of the array.</div> <div><br /></div> <div>The 70 000 Lofar antennas are spread across Europe, with the majority being located in the Netherlands. In standard operation, only the signals from antennas located in the Netherlands are combined, and creates a “virtual telescope” equivalent to a dish with a diameter of 120 kilometres. By using the signals from all the European antennae, the team have increased this diameter to almost 2000 kilometres, which provides twenty-fold sharper resolution.</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/M2_Resolution_Fade_Movie_72dpi_340x340.gif" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /><span style="background-color:initial">Unlike other radio telescope arrays that combine multiple signals in real time to produce images, Lofar uses a new concept where the signals collected by each antenna are digitised, transported to central processor, and then combined to create an image. Each Lofar image is the result of combining the signals from tens of thousands of antennas, which is what makes their extraordinary resolution possible.</span><br /></div> <div><br /></div> <div>- With its network of antennas over the whole of Europe, Lofar is showing us that it’s possible to make astonishingly detailed images of universe as we have never seen it before”, said John Conway, professor of radio astronomy at Chalmers, director of Onsala Space Observatory, and member of the team.</div> <div><br /></div> <div><strong>Jets and outflows from supermassive black holes</strong></div> <div><br /></div> <div>Supermassive black holes can be found lurking at the heart of many galaxies. Many of these are “active” black holes, which devour infalling matter and belch it back out into the cosmos as powerful jets and outflows of radiation. These jets are invisible to the naked eye, but they burn bright in radio waves and it is these that the new high-resolution images have focused upon. </div> <div><br /></div> <div>“These high-resolution images allow us to zoom in to see what’s really going on when supermassive black holes launch radio jets, which wasn’t possible before at frequencies near the FM radio band”, said team </div> <div>member Neal Jackson, University of Manchester, UK.</div> <div><br /></div> <div>The team’s work forms the basis of nine scientific studies that reveal new information on the inner structure of radio jets in a variety of different galaxies. </div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/badole_gravitational_lens_sv_72dpi_340x164.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /><strong style="background-color:initial">A decade-long challenge</strong><br /></div> <div><strong><br /></strong></div> <div>Even before Lofar started operations in 2012, the European team of astronomers began working to address the colossal challenge of combining the signals from more than 70 000 antennas located as much as 2000 km apart. The result, a publicly-available data-processing pipeline, which is described in detail in one of the scientific papers, will allow astronomers from around the world to use Lofar to make high-resolution images with relative ease.</div> <div><br /></div> <div> “Our aim is that this allows the scientific community to use the whole European network of Lofar telescopes for their own science, without having to spend years to become an expert”, said Leah Morabito.</div> <div><br /></div> <div><strong>Super images require supercomputers</strong></div> <div><strong><br /></strong></div> <div>The relative ease of the experience for the end user belies the complexity of the computational challenge that makes each image possible. Lofar doesn’t just take pictures of the night sky; it must stitch together the data gathered by more than 70 000 antennas, which is a huge computational task. To produce a single image, more than 13 terabits of raw data per second – the equivalent of more than a three hundred DVDs every second – must be digitised, transported to a central processor and then combined. </div> <div><br /></div> <div>“To process such immense data volumes we have to use supercomputers. These allow us to transform the terabytes of information from these antennas into just a few gigabytes of science-ready data, in only a couple of days”, said team member Frits Sweijen, Leiden University, Netherlands.</div> <div><br /></div> <div><strong>Contacts:</strong></div> <div> </div> <div>Robert Cumming, communicator, Onsala Space Observatory, Chalmers, tel: +46 70 493 3114, ro-bert.cumming@chalmers.se</div> <div>John Conway, professor of radio astronomy and director of Onsala Space Observatory, Chalmers, +46 31-772 5500, john.conway@chalmers.se</div> <div><br /></div> <div><span style="background-color:initial"><strong>More about Lofar</strong></span><br /></div> <div><br /></div> <div>The International Lofar Telescope is a trans-European network of radio antennas, with a core located in Exloo in the Netherlands. Lofar works by combining the signals from more than 70,000 individual antenna dipoles, located in antenna stations across the Netherlands and in partner European countries. The stations are connected by a high-speed fibre optic network, with powerful computers used to process the radio signals in order to simulate a trans-European radio antenna that stretches over 1,300 kilometres. The International Lofar Telescope is unique, given its sensitivity, wide field-of-view, and image resolution or clarity. The Lofar data archive is the largest astronomical data collection in the world. </div> <div>Lofar was designed, built and is presently operated by Astron, the Netherlands Institute for Radio Astronomy. France, Germany, Ireland, Italy, Latvia, the Netherlands, Poland, Sweden and the UK are all partner countries in the International Lofar Telescope.</div> <div><br /></div> <div><strong>Images</strong></div> <div><strong><br /></strong></div> <div>For a complete set of images, animations and infographics, see the <a href="https://www.astron.nl/most-detailed-ever-images-of-galaxies-revealed-using-lofar/">press release at Astron​</a>.</div> <div><br /></div> <div><em>A – Merging galaxies Arp 299. A galaxy-sized wind is revealed billowing out from a giant star factory, in a dust-enshrouded nucleus, that was triggered as two galaxies merge. Here, Lofar’s observations are shown in orange together with an image taken in visible light by the Hubble Space Telescope. </em><i style="background-color:initial"><a href="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/665x318%20Enskilda%20artikelbilder/arp299_rev_300dpi_full.jpg">Access high-resolution image</a></i><em><br /></em></div> <div><em>Image credit: N. Ramírez-Olivencia et el. [radio]; NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University), edited by R. Cumming [optical]</em></div> <div><em>Science paper: </em><span style="background-color:initial"><i><a href="/SiteCollectionDocuments/Centrum/Onsala%20rymdobservatorium/Forskningsartiklar/P5_MergingGalaxies_Ramirez-Olivencia.pdf">Ramírez-Olivencia m. fl. (pdf)​</a></i></span></div> <div><em><br /></em></div> <div><em>B – Hercules A. This galaxy is powered by a supermassive black hole located at its centre, which feeds on the surrounding gas and channels some of this gas into extremely fast jets. The new high-resolution observations reveal that this jet grows stronger and weaker every few hundred thousand years. This variability produces the beautiful structures seen in the giant lobes, each of which is about as large as the Milky Way galaxy. </em><i style="background-color:initial"><a href="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/665x318%20Enskilda%20artikelbilder/I3_HerculesA_Timmerman_300dpi_full.jpg" style="outline:0px">Access high-resolution image</a></i></div> <div><em>Image credit: R. Timmerman; LOFAR &amp; Hubble Space Telescope</em></div> <div><em>Science paper: </em><span style="background-color:initial"><i><a href="https://doi.org/10.1051/0004-6361/202140880">https://doi.org/10.1051/0004-6361/202140880</a></i></span></div> <div><em><br /></em></div> <div><em>C - Sharper galaxy images with Lofar. This animation shows real radio galaxies from the science paper Morabito et al. (2021). The animation fades from the standard resolution to the high resolution, showing the detail we can see by using the new techniques.</em></div> <div><em>Image credit: L. K. Morabito; LOFAR Surveys KSP</em></div> <div><em>Science paper: </em><span style="background-color:initial"><i><a href="https://doi.org/10.1051/0004-6361/202140649">https://doi.org/10.1051/0004-6361/202140649</a></i></span></div> <div><em><br /></em></div> <div><em>D – Gravitational lens.  Lofar’s observations reveal the structure of a distant galaxy – a quasar - whose light has been bent by gravity around a massive cluster of galaxies in front of it. The illustration in the left panel shows how a gravitational lens works. </em></div> <div><em>Image credit: S. Badole; NASA, ESA &amp; L. Calçada</em></div> <div><em>Science paper: </em><span style="background-color:initial"><i><a href="https://doi.org/10.1051/0004-6361/202141227">https://doi.org/10.1051/0004-6361/202141227</a></i></span></div> ​Tue, 17 Aug 2021 18:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Eclipse-linked-Gothenburg-kids-to-space-and-Chalmers.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Eclipse-linked-Gothenburg-kids-to-space-and-Chalmers.aspxSolar eclipse linked Gothenburg kids to space - and to Chalmers<p><b>​Seeing a solar eclipse can be a memorable experience. In three new Chalmers projects, the solar eclipse on 10 June gave young people extra access to space and to science. But not without a bit of luck with the weather, technology and social distancing.</b></p>​<span style="background-color:initial">One of the sky’s biggest events of the year began at 11:30 on the second Thursday in June, when the moon slid gently in front of the sun, a partial solar eclipse visible from Gothenburg and many other places. The event was also an important part of three different initiatives, in three different places, all with the aim of giving young people extra science capital, with the help of Chalmers. </span><div><br /><span style="background-color:initial"></span><div>In all three locations, plans had been changing, right until the last minute. This was the moment of truth for two school classes and their teachers, a handful of Chalmers students, several radio astronomers and two unsuspecting telescopes.</div> <div><br /></div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/lovgardet_solf_lank_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /></div> <div>On the stone steps to the playground at the Lövgärdesskolan, a school on the north side of Gothenburg, the entire year 4 gathered to look at the eclipse. They were well prepared. Science teacher Catrine Berglund had sneaked in micro-lessons about space throughout the spring term, and students had painted space motifs on corridor walls to add to the excitement. And the day before, Robert Cumming from Onsala Space Observatory had delivered two &quot;sun cradles&quot; for projecting the sun safely.</div> <div><br /></div> <div>The school had also bought in special eclipse glasses for the whole class - useful for anyone who wants to look at the sun. But the clouds looked dishearteningly dense and grey. Would the sun come out at all?</div> <div><br /></div> <div>In Slottsskogen Park in central Gothenburg, another group gathered: a handful of students in the newly started network Upprymd. During the spring, they had met over Zoom to be trained in public engagement about space. Now getting to know each other in person for the first time, they could start their mission as communicative astronomers.</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/slottsskogen2_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><span style="background-color:initial">​</span></div> <div>Equipped with binoculars and a cardboard screen, the plan was to show the eclipse to other park visitors. Here, clouds and eye protection were part of the challenge. How could they balance keeping a good corona-safe distance, but at the same time being open and friendly?</div> <div><br /></div> <div>South of the city, at Onsala Space Observatory, Robert Cumming and Eskil Varenius took the opportunity to try a new way of viewing the solar eclipse with the observatory's smallest radio telescopes, SALSA, as part of a third project, “SALSA for years 7-9”, funded by the Swedish Research Council. With an improved user interface, SALSA is currently being adapted to make radio astronomy projects possible for students in their younger teens. </div> <div><br /></div> <div>Here, at least, the weather wasn’t a problem. Radio telescopes can see the sky through thick clouds, and SALSA is no exception. But they had never been used before to see a solar eclipse, and the software was also brand new and untested. On top of that, the plan was to show SALSA live on a link for the school in Gothenburg. Would it really succeed?</div> <div><br /></div> <div>And just where had the sun got to? The wait was nervous in all three places. Gaps finally appeared in the clouds, first in Onsala, then over the park, and finally also at the schoolyard, but those moments were few and easy to miss.</div> <div><br /></div> <div>There! The round disk of the sun, clearly with a chunk missing! For those who got a look, it really was a moment to remember. </div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/salsa_solf_20210610_72dpi_340x277.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /></div> <div><br /></div> <div>The kids on the school stairs didn’t all see the eclipse, but everyone had experienced something out of the ordinary. A reporter from local radio station was on hand to broadcast live, and young enthusiasts Amina and Huzaifa and their friends got to explain the phenomenon to the listeners. In the city park, the students chose eclipse glasses over projection as the best way to share the sight of the cloud-shrouded eclipse, but everyone was satisfied in the end. In Onsala, the measurements clearly showed that the moon really had blocked some of the sun’s radio waves - the experiment was successful. Network issues affected the live connection to the school (and to some extent also the observatory's high-tech reputation). But contact was made and everyone got to say hi.</div> <div><br /></div> <div>After almost two hours, the sun was back to being whole again and it was all over for this time. However, all three projects will continue during the rest of the year. At the school, a special space day is planned for 23 September 2021. For the student network Upprymd, there will be online question and answer sessions with school classes and other events. They’ll also test SALSA and its new software, and start to help school students and teachers make their own radio observations.</div> <div><br /></div> <div>For the solar eclipse over western Sweden we’ll have to wait until 25 October 2022. What are we going to come up with for that? With a bit more science capital to spare, there will be new opportunities for everyone.</div> <div>The project with Lövgärdesskolan is run in collaboration with the City of Gothenburg, the housing company Poseidon and space industry company CAES (Cobham Gaisler).</div> <div><br /></div> <div>Text: Robert Cumming</div> <div><br /></div> <div><em>Images:</em></div> <div><em><br /></em></div> <div><em>A (top) </em><span style="background-color:initial"><em>Johannes Reldin photographed the eclipsed sun through the mesh of one of the SALSA antennas. </em></span></div> <em> </em><div><br /></div> <div><em>B </em><span style="background-color:initial"><em>S</em></span><span style="background-color:initial"><em>ALSA and Robert Cumming on a live </em></span><span style="background-color:initial"><em>link from Onsala with year 4 students. Photo: Eva Loström/Lövgärdesskolan</em></span></div> <em> </em><div><br /></div> <div><em>C Students in the Upprymd network watching the eclipse in Slottsskogen park. Credit: Andri Spilker</em></div> <div><em> </em></div> <em> </em><div><em>D Radio partial eclipse:  the top graph shows measurements with SALSA throughout the day on 10 June 2021. During the solar eclipse (dashed lines mark its beginning and end) the radio waves from the sun were clearly less than usual. (Credit: Eskil Varenius)</em></div> ​</div>Fri, 18 Jun 2021 09:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Water-from-interstellar-clouds-to-habitable-planets.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Water-from-interstellar-clouds-to-habitable-planets.aspxFrom interstellar clouds to habitable planets<p><b>​An international team of astronomers, among them scientists from Chalmers, has published a comprehensive survey of water’s journey through space. Using data from the Herschel Space Observatory, they have shown that life's most important molecule can thrive in all new-born solar systems - not just ours.</b></p><div>Only ten years ago, it was not known how and where water is formed in space, and how it eventually ends up on a planet like Earth. </div> <div><br /></div> <div>Now, an international research team has put together everything scientists know about water in interstellar clouds, and the origin of water on newborn, potentially habitable, planets. The article, published in the journal Astronomy &amp; Astrophysics, is based on observations with the Herschel Space Observatory. </div> <div><br /></div> <div><strong style="background-color:initial">Space telescopes</strong><br /></div> <div><br /></div> <div><span></span><div><span style="background-color:initial">Seeing water in space </span>is a challenge for astronomers. Even the best ground-based telescopes are affected by water vapour in our own atmosphere.</div> <div><br /></div> <div><div><span style="background-color:initial">Following an early pioneering effort by </span><a href="/sv/institutioner/see/nyheter/Sidor/Satelliten-Odin-firar-20-ar-i-rymden.aspx" style="outline:0px">the Swedish science satellite Odin​</a><span style="background-color:initial">, the Herschel Space Observatory was launched in 2009 by the European Space Agency, ESA.</span><br /></div></div> <div><br /></div> <div>During its four-year mission, Herschel had as one of its main objectives to investigate water in space. Of particular importance was the instrument HIFI, which was built under Dutch leadership with important contributions from Sweden, and in particular from Chalmers.</div></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">In the new study, Ewine van Dishoeck and her colleagues have been able to study how water molecules follow each part of the process that leads to the birth of new stars and planets.</span><br /></div> <div><span style="background-color:initial"><br /></span></div> <div><strong>Starts with Ice</strong></div> <div><span style="background-color:initial"><div><br /></div> <div><span style="background-color:initial">The new study shows that </span><span style="background-color:initial"></span><span style="background-color:initial">most of the water is formed as ice on tiny dust particles in cold and tenuous interstellar clouds.</span></div> <div><span style="background-color:initial"><br /></span></div> <div>When a cloud collapses into new stars and planets, this water is largely preserved and quickly anchored into pebble-sized dust particles. In the rotating disk around the young star, these pebbles then form the building blocks for new planets.<br /></div> <div><br /></div></span></div> <div> <div>&quot;Water is mostly transported as ice from large interstellar clouds to these disks. The ice seems not to melt or break up on the way in. We can't say yet exactly how much water there is in these disks, but it's enough to form oceans on Earth-like planets&quot;, says Per Bjerkeli, astronomer at Chalmers.<br /></div> <div><br /></div> <div>Earth's water has also migrated here in this way, the researchers believe. <span style="background-color:initial">Furthermore, they have calculated that most new solar systems are born with enough water to fill several thousand oceans. </span><br /></div> <div><br /></div> <div><span style="background-color:initial">&quot;It's fascinating to realise that when you drink a glass of water, most of those molecules were made more than 4.5 billion years ago in the cloud from which our sun and the planets formed&quot;, says Ewine Van Dishoeck.</span><br /></div> <div><span style="background-color:initial"><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/Rho_Ophiuchi_star-forming_region_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><br /></span><span style="background-color:initial">For water molecules, the road from interstellar clouds to the drinking glass is complex, the scientists show. Previous studies with the Herschel Space Observatory showed how </span><span style="background-color:initial">hot water vapour seen and copiously produced near forming stars is lost to space in powerful outflows.</span><span style="background-color:initial"> Now, the researchers have also been able to trace both cold water vapor and ice deposits in these star systems, among other things by examining weak signals from heavy water (where the molecule H<sub>2</sub>0 contains one or two atoms of heavy hydrogen, or deuterium).</span><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">Many mysteries remain concerning water's path to the planets which new and future telescopes will have to address. NASA/ESA's James Webb telescope, which will be launched later this year, as well as the radio telescope ALMA in Chile and the future radio telescope SKA all have roles to play. The instrument </span><span style="background-color:initial">MIRI</span><span style="background-color:initial"> </span><span style="background-color:initial">on board the James Webb Telescope </span><span style="background-color:initial">will be able to detect warm water vapour in the innermost zones of dust disks.</span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">– </span><span style="background-color:initial">Herschel has already shown that planet-forming disks are rich in water ice. With MIRI we can now follow that trail into the regions where Earth-like planets are formed, says </span><span style="background-color:initial">Michiel Hogerheijde, astronomer at Leiden University and the University of Amsterdam.</span><span style="background-color:initial">​</span></div> <div><br /></div> <div>Press release in English from NOVA: <a href="https://www.astronomie.nl/nieuws/en/long-awaited-review-reveals-journey-of-water-from-interstellar-clouds-to-habitable-worlds-2733" style="outline:0px">https://www.astronomie.nl/nieuws/en/long-awaited-review-reveals-journey-of-water-from-interstellar-clouds-to-habitable-worlds-2733</a></div> <div><br /></div> <div><strong>More about the research and the Herschel Space Observatory </strong></div> <strong> </strong><div><br /></div> <span style="background-color:initial">Herschel was a space telescope of the European Space Agency (ESA) built in cooperation with NASA. Its HIFI and PACS instruments were used for the water research. HIFI was designed and built by a consortium of institutes and university departments across Europe, Canada, and the United States under the leadership of SRON Netherlands Institute for Space Research, the Netherlands, with major contributions from Germany, France, and the USA. The PACS instrument was developed by a consortium of institutes and universities across Europe led by the Max Planck Institute for Extraterrestrial Physics in Germany. Chalmers scientists played an active role in the scientific planning for Herschel, and were involved in several projects using data from the telescope.</span></div> <div><span style="background-color:initial">​<br /></span></div> <div><span style="background-color:initial">​<img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/Water_trail-credit-ESA-ALMA-NASA-LE-Kristensen_72dpi_340x254.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" />The results are </span><span style="background-color:initial">published in a paper by Ewine F. van Dishoeck et al., <em>Water in star-forming regions: Physics and chemistry from clouds to disks as probed by Herschel spectroscopy, </em>in the journal Astronomy &amp; Astrophysics. Link to the paper: </span><a href="https://www.aanda.org/10.1051/0004-6361/202039084">https://www.aanda.org/10.1051/0004-6361/202039084​</a><span style="background-color:initial"> (see also </span><a href="https://arxiv.org/abs/2102.02225">https://arxiv.org/abs/2102.02225</a><span style="background-color:initial">).</span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial"><div>Ewine van Dishoeck led the water research programme WISH (<a href="http://www.strw.leidenuniv.nl/WISH/">Water in Star-forming regions with Herschel</a>). ​The team consists of 50 astronomers, among them Chalmers scientists Per Bjerkeli, René Liseau och Magnus Persson, and Bengt Larsson (Stockholm University).</div> <div><br /></div> <div><em>Images</em></div> <em> </em><div><br /></div> <em> </em><div><div><em>A (top) - The path of water molecules from vast interstellar clouds to potentially habitable planets has been traced in the star-forming region Rho Ophiuchi, 440 light years distant in the constellation Ophiuchus. This wide-angle image from Herschel, taken in light with a wavelength between 70 and 250 micrometers with the telescope's camera PACS, is 4 degrees wide (equivalent to eight full moons). In the brightest part of the image (above right) lies the young star VLA 1623, subject of detailed observations of water with the instrument HIFI.</em></div> <em> </em><div><em>Image: ESA / Herschel / NASA / JPL-Caltech, CC BY-SA 3.0 IGO; Acknowledgment: R. Hurt (JPL-Caltech)</em></div> <em> </em><div><a href="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/750x340/Rho_Ophiuchi_star-forming_region_H2O_300dpi_full.jpg"><em>Download high resolution image (with molecules)</em></a><em> or </em><a href="https://sci.esa.int/web/herschel/-/59533-herschel-s-view-of-rho-ophiuchi"><em>see the original image at ESA</em></a></div> <em> </em><div><br /></div> <em> </em><div><em>B - The </em><span style="background-color:initial"><em>star-forming region </em></span><span style="background-color:initial"><em>Rho Ophiuchi, 440 light</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>years</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>distant </em></span><span style="background-color:initial"><em>in the constellation</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>Ophiuchus</em></span><span style="background-color:initial"><em>. This wide-angle image from</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>Herschel,</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>taken in light with a wavelength between 70 and 250 micrometers with the telesco</em></span><span style="background-color:initial"><em>pe'</em></span><span style="background-color:initial"><em>s camera</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>PACS, is 4 degrees wide (equivalent to eight full moons). In the brightest part</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>of the image</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>(above right) lies</em></span><span style="background-color:initial"><em> the young star VLA 1623,</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>subject of</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>detailed observations</em></span><span style="background-color:initial"><em> </em></span><span style="background-color:initial"><em>of water with the instrument HIFI.</em></span></div> <em> </em><div><em>Image: ESA / Herschel / NASA / JPL-Caltech, CC BY-SA 3.0 IGO; Acknowledgment: R. Hurt (JPL-Caltech)</em></div> <em> </em><div><a href="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/750x340/Rho_Ophiuchi_star-forming_region_300dpi_full.jpg"><em>Download high resolution image (without molecules)</em></a><em> or </em><a href="https://sci.esa.int/web/herschel/-/59533-herschel-s-view-of-rho-ophiuchi"><em>view in original version at ESA</em></a></div> <em> </em><div><br /></div> <em> </em><div><em>C - This illustration shows the </em><span style="background-color:initial"><em>Journey of water from interstellar clouds to habitable worlds. From top left to bottom right: water in a cold interstellar cloud, near a young, forming star with an outflow, in a protoplanetary disc, in a comet and in the oceans of an exoplanet. The first three stages show the spectrum of water vapour measured by the HIFI instrument on the Herschel space observatory. The signals from the cold interstellar cloud and from the protoplanetary disk have been exaggerated in this image by a factor of 100 compared to those from the young, forming star in the centre.​</em></span></div> <em> </em><div><em>Image: ESA / ALMA / NASA / L. E. Kristensen</em></div></div> <div><em><br /></em></div> <div><div><strong>Contacts</strong></div> <div><br /></div> <div>Robert Cumming, communications officer, Onsala Space Observatory, +46 70 493 31 14, robert.cumming@chalmers.se</div> <div><br /></div> <div>Per Bjerkeli, astronomer, Department of Space, Earth and Environment, +46 31 772 64 30, per.bjerkeli@chalmers.se</div></div> <div><br /></div></span></div>Wed, 14 Apr 2021 15:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/EHT-magnetic-fields-M87-black-hole.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/EHT-magnetic-fields-M87-black-hole.aspxBlack hole's magnetic fields revealed by the Event Horizon Telescope<p><b>​​A new view of the supermassive black hole shows the centre of galaxy M 87 in polarised light. The observations with the Event Horizon Telescope (EHT) reveal how energetic jets form close to the black hole, 55 million light years distant. Astronomers from Chalmers are part of the international EHT collaboration.</b></p>​<span style="background-color:initial">The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has revealed a new view of the massive object at the centre of the galaxy Messier 87 (M87): how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the galaxy, located 55 million light-years away, is able to launch energetic jets from its core.</span><div><br /></div> <div>“We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy,” says Monika Mościbrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud University in the Netherlands.</div> <div><br /></div> <div>On 10 April 2019, scientists released the first ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole’s shadow. Since then, the EHT collaboration has delved deeper into the data on the supermassive object at the heart of the M87 galaxy collected in 2017. They have discovered that a significant fraction of the light around the M87 black hole is polarised.</div> <div><br /></div> <div>“This work is a major milestone: the polarisation of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before,” explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the University of Valencia, Spain. He adds that “unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analysing the data.”</div> <div><br /></div> <div>Light becomes polarised when it goes through certain filters, like the lenses of polarised sunglasses, or when it is emitted in hot regions of space where magnetic fields are present. In the same way that polarised sunglasses help us see better by reducing reflections and glare from bright surfaces, astronomers can sharpen their view of the region around the black hole by looking at how the light originating from it is polarised. Specifically, polarisation allows astronomers to map the magnetic field lines present at the inner edge of the black hole. </div> <div><br /></div> <div>“The newly published polarised images are key to understanding how the magnetic field allows the black hole to 'eat' matter and launch powerful jets,” says EHT collaboration member Andrew Chael, a NASA Hubble Fellow at the Princeton Center for Theoretical Science and the Princeton Gravity Initiative in the US.</div> <div><br /></div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/eso2105b_72dpi_340x227.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /></div> <div>The bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its centre are one of the galaxy’s most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets. </div> <div><br /></div> <div><span style="background-color:initial">Astronomers have relied on different models of how matter behaves near the black hole to better understand this process. But they still don’t know exactly how jets larger than the galaxy are launched from its central region, which is comparable in size to the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarised light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening. </span><br /></div> <div><br /></div> <div>The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetised gas can explain what they are seeing at the event horizon. </div> <div><br /></div> <div>“The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon,” explains Jason Dexter, Assistant Professor at the University of Colorado Boulder, US, and Coordinator of the EHT Theory Working Group. </div> <div><br /></div> <div>To observe the heart of the M87 galaxy, the collaboration linked eight telescopes around the world – including the ALMA (Atacama Large Millimeter/submillimeter Array) and APEX (Atacama Pathfinder EXperiment) in northern Chile – to create a virtual Earth-sized telescope, the EHT. The impressive resolution obtained with the EHT is equivalent to that needed to measure the length of a credit card on the surface of the Moon.</div> <div><br /></div> <div>“With ALMA and APEX, which through their southern location enhance the image quality by adding geographical spread to the EHT network, European scientists were able to play a central role in the research,” says Ciska Kemper, European ALMA Programme Scientist at ESO. “With its 66 antennas, ALMA dominates the overall signal collection in polarised light, while APEX has been essential for the calibration of the image.”</div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/eso2105d_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /></div> <div><br /></div> <div>&quot;ALMA data were also crucial to calibrate, image and interpret the EHT observations, providing tight constraints on the theoretical models that explain how matter behaves near the black hole event horizon,&quot; adds Ciriaco Goddi, a scientist at Radboud University and Leiden Observatory, the Netherlands, who led an accompanying study that relied only on ALMA observations.</div> <div><br /></div> <div>The EHT setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetised. The results are published today in two separate papers <span style="background-color:initial">by the EHT collaboration </span><span style="background-color:initial">in </span><span style="background-color:initial">Astrophysical Journal Letters</span><span style="background-color:initial">. </span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">The research involved over 300 researchers from multiple organisations and universities worldwide. </span></div> <div></div> <div><br /></div> <div><div>Chalmers scientists Michael Lindqvist and John Conway, <span style="background-color:initial">both at</span><span style="background-color:initial"> </span><span style="background-color:initial">Onsala Space Observatory and the Department of Space, Earth and Environment, </span><span style="background-color:initial">represent Sweden in the EHT collaboration. </span><span style="background-color:initial"></span></div> <div></div> <div><br /></div> <div> &quot;In Onsala we have participated <span style="background-color:initial">since the 1960s </span><span style="background-color:initial">in the development of very long baseline interferometry (VLBI),</span><span style="background-color:initial"> the technique used in the EHT. </span><span style="background-color:initial"></span><span style="background-color:initial">Onsala Space Observatory</span><span style="background-color:initial"> is one of three partners in APEX, one of the telescopes in the EHT network, and we have worked for many years with our partners building up capacity for VLBI at APEX&quot;, says Michael Lindqvist.</span></div> <span></span><div></div> <div><br /></div> <div>“The Swedish contribution to this research has been significant&quot;, says Iván Martí-Vidal, who worked at Onsala Space Observatory until 2018. “The observatory in Onsala has also been responisble for calibrating ALMA data, and its role as a partner in the APEX telescope has been critical for being able to calculate and correct for the instrumental polarisation in ALMA.&quot; </div> <div><br /></div> <div>Detailed knowledge of these aspects is of great importance for the conclusions about the supermassive black hole that have now been presented.</div> </div> <div><br /></div> <div><strong>More information</strong></div> <div><br /></div> <div>This research is presented in two papers by the EHT collaboration published on 24 March 2021 in Astrophysical Journal Letters: &quot;First M87 Event Horizon Telescope Results VII: Polarization of the Ring&quot; (doi: 10.3847/2041-8213/abe71d) and &quot;First M87 Event Horizon Telescope Results VIII: Magnetic Field Structure Near The Event Horizon&quot; (doi: 10.3847/2041-8213/abe4de). Accompanying research is presented in the paper &quot;Polarimetric properties of Event Horizon Telescope targets from ALMA&quot; (doi: 10.3847/2041-8213/abee6a) by Goddi, Martí-Vidal, Messias, and the EHT collaboration, which has been accepted for publication in ​​Astrophysical Journal Letters.</div> <div><br /></div> <div><a href="https://www.eso.org/public/sweden/news/eso2105/">See ESO's press release for links to the science papers and more background information</a><span style="background-color:initial">.</span><br /></div> <div><span style="background-color:initial"><br /></span></div> <div><div><span style="font-weight:700">Contacts</span></div> <div><br /></div> <div>Robert Cumming, communications officer, Onsala Space Observatory, Chalmers, +46 70-493 31 14, robert.cumming@chalmers.se</div> <div><br /></div> <div>Michael Lindqvist, astronomer, Onsala Space Observatory, Chalmers, michael.lindqvist@chalmers.se</div> <div><br /></div> <div><em><strong>Images</strong></em></div> <div><em><br /></em></div> <div><span></span><a href="https://www.eso.org/public/sweden/news/eso2105/"><em>See ESO's press release for high-resolution images</em></a><span style="background-color:initial"><em>.</em></span><br /></div> <div><br /></div> <div><div><i>A (överst) - <span style="background-color:initial"></span></i><span style="background-color:initial"><i>A view of the M87 supermassive black hole in polarised light. </i></span><span style="background-color:initial"><i>The lines mark the orientation of polarisation, which is related to the magnetic field around the shadow of the black hole.</i></span></div> <div><span style="background-color:initial"><i>Bild: EHT-samarbetet</i></span></div> <div><i><br /></i></div> <div><i>B - Composite image showing </i><span style="background-color:initial"><i>M 87's supermassive black hole and jet, as seen in polarized light. Images from different radio telescopes show the jet's polarisation at different scales. Top: ALMA observations taken at the same time as the EHT observations. In the middle are measurements with the VLBA in the USA. The EHT observations are shown at the bottom of the image.</i></span></div> <div><i>Bild: <span style="background-color:initial">EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal</span></i></div> <div><i><br /></i></div> <div><i>C: Jetstrålen i M 87 i polariserat ljus uppmätt av ALMA. </i></div> <div><i>Bild: ALMA (ESO/NAOJ/NRAO), Goddi et al.</i><br /></div></div> <div><i><br /></i></div> <div><br /></div> <div><br /></div> <span style="background-color:initial"></span></div> <div><br /></div> <div><br /></div>Wed, 24 Mar 2021 15:00:00 +0100https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/SKAO-birth-of-a-new-global-observatory.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/SKAO-birth-of-a-new-global-observatory.aspxSKAO: birth of a new global observatory<p><b>​A new, global intergovernmental organization in radio astronomy has been founded. The SKA Observatory (SKAO) will build and operate the world's largest and most complex radio telescopes to answer big questions about the universe. Chalmers leads Sweden's participation in the project.</b></p>​<span style="background-color:initial">The new observatory, SKAO, was launched on 4 February 2021 when the first meeting of its governing Council was held. The observatory is the world’s second intergovernmental organisation dedicated to astronomy. </span><div>Catherine Cesarsky has been appointed as the first Chair of the SKAO Council.</div> <div><br /></div> <div>“This is a historic moment for radio astronomy”, she said. “Behind today’s milestone, there are countries that had the vision to get deeply involved because they saw the wider benefits their participation in SKAO could bring to build an ecosystem of science and technology involving fundamental research, computing, engineering, and skills for the next generation, which are essential in a 21st century digital economy.”</div> <div><br /></div> <div>The new observatory has its headquarters at on the grounds of the Jodrell Bank UNESCO World Heritage Site in the United Kingdom, with telescopes located at sites in Australia and South Africa.</div> <div><br /></div> <div>SKAO’s telescope in South Africa will be composed of 197 dish antennas, each 15 m in diameter, located in the Karoo region. Of these, 64 already exist and are operated by the South African Radio Astronomy Observatory (SARAO). The telescope in Australia will be composed of 131 072 two-metre-tall antennas located on the Commonwealth Scientific and Industrial Research Organisation’s (CSIRO) Murchison Radio-astronomy Observatory. </div> <div><br /></div> <div>The creation of SKAO follows a decade of detailed engineering design work, scientific prioritisation, and policy development under the supervision of its predecessor the SKA Organisation, supported by more than 500 engineers, over 1,000 scientists and dozens of policy-makers in more than 20 countries; and is the result of 30 years of thinking and research and development since discussions first took place about developing a next-generation radio telescope.</div> <div><br /></div> <div>Philip Diamond, professor at the University of Manchester, has been appointed as the first Director-General of SKAO.</div> <div><br /></div> <div>“Today marks the birth of a new observatory,” he said. “And not just any observatory – this is one of the mega-science facilities of the 21st century. It is the culmination of many years of work and I wish to congratulate everyone in the SKA community and in our partner governments and institutions who have worked so hard to make this happen. For our community, this is about participating in one of the great scientific adventures of the coming decades. It is about skills, technology, innovation, industrial return, and spin offs but fundamentally it is about a wonderful scientific journey that we are now embarking on.” </div> <div><br /></div> <div>Lars Börjesson, professor of physics at Chalmers, is Sweden’s representative as an observer to the SKAO Council.</div> <div><br /></div> <div>“The establishment of the SKA Observatory is a major event for the field of radio astronomy, and a decisive organisational step towards the construction of the SKA telescope”, he said. “We’ve reached this milestone thanks to a huge amount of work in a truly global network, involving the world’s leading radio astronomy institutes and observatories. Together, across international borders, we have combined expertise and enthusiasm to develop the SKA’s science goals, its technical design and organisational structure, and this is something we can be really proud of. For Sweden, funding has now been secured for participation in the construction phase, and the formal process for membership in the SKA Observatory has been initiated.”</div> <div><br /></div> <div>The first SKAO Council meeting follows the signature of the SKA treaty, formally known as the convention establishing the SKA Observatory, on 12 March 2019 in Rome, and its subsequent ratification by Australia, Italy, the Netherlands, Portugal, South Africa and the United Kingdom and entry into force on 15 January 2021, marking the official birth date of the observatory.</div> <div><br /></div> <div>The council is composed of representatives from the Observatory’s Member States, as well as observer countries aspiring to join SKAO. Sweden is one of several observer countries that took part in the design phase of the SKA, along with Canada, China, France, Germany, India, Spain and Switzerland. These countries’ future accession to SKAO is expected in the coming weeks and months, once their national processes have been completed. Representatives of national bodies in Japan and South Korea complement the select list of observers in the SKAO Council.</div> <div><br /></div> <div>At its first meeting, the SKAO Council approved policies and procedures that have been prepared in recent months – covering governance, funding, programmatic and HR matters, among others. These approvals are required to transfer staff and assets from the SKA Organisation to the observatory.</div> <div><br /></div> <div>“The coming months will keep us very busy, with hopefully new countries formalising their accession to SKAO and the expected key decision of the SKAO Council giving us green light to start the construction of the telescopes,” added Prof. Diamond.</div> <div><br /></div> <div>SKAO will begin recruitment in Australia and South Africa in the next few months, working alongside local partners CSIRO and SARAO to supervise construction, which is expected to last eight years, with early science opportunities starting in the mid 2020s. </div> <div><br /></div> <div><strong>About the SKA Observatory</strong></div> <div><br /></div> <div>SKAO, formally known as the SKA Observatory, is a global collaboration of member states to build and operate cutting-edge radio telescopes to answer fundamental questions about our universe. Headquartered in the UK, its first two telescopes, the two largest and most complex radio telescope networks ever built, will be constructed in Australia and South Africa. A later expansion is envisioned in both countries and other African partner countries. SKAO’s telescopes will conduct transformational science and, together with other state-of-the-art research facilities, address gaps in our understanding of the universe including the formation and evolution of galaxies, fundamental physics in extreme environments and the origins of life. Through the development of innovative technologies and its contribution to addressing global societal challenges, SKAO will play its part to address the United Nations’ Sustainable Development Goals and deliver significant non-science impact across its membership and beyond. </div> <div><br /></div> <div>Current SKAO Members are Australia, Italy, the Netherlands, Portugal, South Africa and the United Kingdom with several other countries, among them Sweden, aspiring to membership or engagement with SKAO in the future.</div> <div><br /></div> <div><strong>About Onsala Space Observatory and Sweden’s role in the SKA project</strong></div> <div><br /></div> <div>Onsala Space Observatory is Sweden's national facility for radio astronomy. The observatory provides researchers with equipment for the study of the earth and the rest of the universe. In Onsala, 45 km south of Gothenburg, it operates four radio telescopes and a station in the international telescope Lofar. The SKA is one of several international projects that the observatory participates in. The observatory is hosted by the Department of Space, Earth and Environment at Chalmers University of Technology, and is operated on behalf of the Swedish Research Council.</div> <div><br /></div> <div>Between 2012 and 2021, Onsala Space Observatory represented Sweden as a member country of the SKA Organization. Chalmers and Onsala Space Observatory have been working on the development of the SKA since its inception. Scientists in Sweden have worked both in preparing the SKA's scientific programme, and developing the technical components and systems that the telescopes need to be able to make new discoveries. Sweden has contributed with the development and prototypes of receivers for SKA's dish antennas, for example unique low-noise amplifiers.</div> <div><br /></div> <div>With the support of Big Science Sweden, Chalmers and Onsala Space Observatory engaged companies in the SKA at an early stage, particularly in areas where Sweden is strong (e.g. radio and microwave engineering, ICT and signal processing), developing close collaborations with several universities and institutes. Thanks to both technical development work and cooperation with other research organizations involved in SKA's development, Sweden has been able to lead the completion and delivery of two important systems for SKA’s telescope in South Africa (about 200 receivers for the frequency band 350 - 1050 MHz, low noise amplifiers for several frequency bands and digitising systems for faint signals). In this work, Sweden works together with colleagues in Canada, France, India, Spain and South Africa.</div> <div><br /></div> <div><strong>Contacts</strong></div> <div><br /></div> <div>Robert Cumming, communicator, Onsala Space Observatory, Chalmers, tel: +46 31-772 5500 or +46 70 493 3114, robert.cumming@chalmers.se.</div> <div>John Conway, professor and director, Onsala Space Observatory, Chalmers, +46 31-772 5500, john.conway@chalmers.se</div> <div><br /></div> <div><em>Images</em></div> <div><br /></div> <div><em>A (top) - </em><span style="background-color:initial"><em>Composite image of the SKA combining all elements in South Africa and Australia. This image blends photos of real hardware already on the ground on both sites with artist's impressions of the future SKA antennas. From left: artist's impression of the future SKA dishes blend into the existing precursor MeerKAT telescope dishes in South Africa. From right: artist's impression of the future SKA-Low stations blends into the existing AAVS2.0 prototype station in Western Australia.</em></span></div> <div><em>Credit: SKA Organisation</em></div> <div><em><br /></em></div> <div><div><span style="background-color:initial"><i>Mer information och material finns på <a href="http://www.skaobservatory.org/">www.skaobservatory.org</a> och <a href="http://www.skatelescope.org/">www.skatelescope.org</a></i></span></div> <div><span style="background-color:initial"><a href="https://www.skatelescope.org/news/skao-is-born/">Read this release at the SKAO​</a></span></div> <div><i style="background-color:initial"><a href="https://www.skatelescope.org/ska-prospectus/">SKAO Prospectus</a></i><br /></div> <div><i><a href="https://www.dropbox.com/sh/0kv5dmufp8o1fq0/AAA9Bhi3t5E1riZX4c9BNIXba?dl=0">SKAO Media Kit</a></i></div> <div><i><a href="https://www.skatelescope.org/news/dr-cesarsky-elected-chair-of-the-board-of-directors/">About Catherine Cesarsky</a></i></div> <div><i><a href="https://www.skatelescope.org/news/ska-organisation-appoints-new-director-general-for-worlds-largest-telescope-project/">About Philip Diamond</a></i></div> <em></em></div> <div><br /></div> ​Fri, 05 Feb 2021 17:00:00 +0100https://www.chalmers.se/en/departments/see/news/Pages/Dancing-exoplanets.aspxhttps://www.chalmers.se/en/departments/see/news/Pages/Dancing-exoplanets.aspxDancing exoplanets challenge theories on planet formation<p><b>Astronomers have revealed a system consisting of six exoplanets, five of which are locked in a rare rhythm around their central star. The researchers believe the system could provide important clues about how planets, including those in the Solar System, form and evolve.</b></p><p>The Swedish research contribution in this study has been significant, with the participation of, among others, Malcolm Fridlund and Carina Persson at Chalmers University of Technology.<br /><span style="background-color:initial"></span></p> <p><br /></p> <div><span style="background-color:initial"><div>The first time the team observed TOI-178, a star some 200 light-years away in the constellation of Sculptor, they thought they had spotted two planets going around it in the same orbit. However, a closer look revealed something entirely different. </div> <div><br /></div> <div>– Through further observations we realised that there were not two planets orbiting the star at roughly the same distance from it, but rather multiple planets in a very special configuration, says Adrien Leleu from the Université de Genève and the University of Bern, Switzerland, who led a new study of the system published today in Astronomy &amp; Astrophysics.</div> <div><br /></div> <div>The new research has revealed that the system boasts six exoplanets and that all but the one closest to the star are locked in a rhythmic dance as they move in their orbits. In other words, they are in resonance. This means that there are patterns that repeat themselves as the planets go around the star, with some planets aligning every few orbits. </div> <div><br /></div> <div>The five outer exoplanets of the TOI-178 system follow a complex chain of resonance, one of the longest yet discovered in a system of planets. The five outer planets in the TOI-178 system follow a 18:9:6:4:3 chain: while the second planet from the star (the first in the resonance chain) completes 18 orbits, the third planet from the star (second in the chain) completes 9 orbits, and so on. </div> <div><br /></div> <div>The six exoplanets found are very close to the star, with orbital periods ranging from 2 to 21 days, which is closer than the the star's so called habitable zone. But the researchers suggest that, by continuing the resonance chain, they might find additional planets that could exist in or very close to this zone. <br /></div> <div><br /></div> <div>– For a planet to be in the habitable zone where liquid water can be found on the surface, the orbital period in this system must be at least 40 days. The fact that the planets around TOI-178 have orbits so extremely close to their star means that any water on their surfaces would boil away, even though the star is cooler than our Sun, says Carina Persson, at the department of Space, Earth and Environment.<br /></div> <div><br /></div> <div><div><span style="background-color:initial">Read the full press release from ESO, European Southern Observatory: </span><span style="background-color:initial"><a href="https://www.eso.org/public/news/eso2102/?lang">Puzzling six-exoplanet system with rhythmic movement challenges theories of how planets form</a>.</span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial">The study is published in the article: </span><a href="https://www.eso.org/public/archives/releases/sciencepapers/eso2102/eso2102a.pdf"><div style="display:inline !important"><span style="background-color:initial">&quot;</span><span style="background-color:initial">Six transiting planets and a chain of Laplace resonances in</span></div></a></div> <div><a href="https://www.eso.org/public/archives/releases/sciencepapers/eso2102/eso2102a.pdf"><span style="background-color:initial">TOI-178&quot;</span><span style="background-color:initial">, in Astronomy and Astrophysics</span></a><span style="background-color:initial">. </span></div></div></span></div>Wed, 27 Jan 2021 00:00:00 +0100https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Cosmic-flashes-different-sizes-fast-radio_bursts.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Cosmic-flashes-different-sizes-fast-radio_bursts.aspxCosmic flashes come in all different sizes<p><b>​By studying the site of a spectacular stellar explosion seen in April 2020, a Chalmers-led team of scientists have used four European radio telescopes to confirm that astronomy’s most exciting puzzle is about to be solved. Fast radio bursts, unpredictable millisecond-long radio signals seen at huge distances across the universe, are generated by extreme stars called magnetars – and are astonishingly diverse in brightness. </b></p>​<span style="background-color:initial">For over a decade, the phenomenon known as fast radio bursts has excited and mystified astronomers. These extraordinarily bright but extremely brief flashes of radio waves – lasting only milliseconds – reach Earth from galaxies billions of light years away. </span><div><br /></div> <div>In April 2020, one of the bursts was for the first time detected from within our galaxy, the Milky Way, by radio telescopes CHIME and STARE2. The unexpected flare was traced to a previously-known source only 25 000 light years from Earth in the constellation of Vulpecula, the Fox, and scientists all over the world coordinated their efforts to follow up the discovery.</div> <div><br /></div> <div>In May, a team of scientists led by Franz Kirsten (Chalmers) pointed four of Europe’s best radio telescopes towards the source, known as SGR 1935+2154. Their results are published today in a paper in the journal Nature Astronomy.</div> <div><br /></div> <div>“We didn’t know what to expect. Our radio telescopes had only rarely been able to see fast radio bursts, and this source seemed to be doing something completely new. We were hoping to be surprised!”, said Mark Snelders, team member from the Anton Pannekoek Institute for Astronomy, University of Amsterdam. </div> <div><br /></div> <div>The radio telescopes, one dish each in the Netherlands and Poland and two at Onsala Space Observatory in Sweden, monitored the source every night for more than four weeks after the discovery of the first flash, a total of 522 hours of observation.</div> <div><br /></div> <div>On the evening of May 24, the team got the surprise they were looking for. At 23:19 local time, the Westerbork telescope in the Netherlands, the only one of the group on duty, caught a dramatic and unexpected signal: two short bursts, each one millisecond long but 1.4 seconds apart. </div> <div><br /></div> <div>Kenzie Nimmo, astronomer at Anton Pannekoek Institute for Astronomy and ASTRON, is a member of the team.</div> <div><br /></div> <div>“We clearly saw two bursts, extremely close in time. Like the flash seen from the same source on April 28, this looked just like the fast radio bursts we’d been seeing from the distant universe, only dimmer. The two bursts we detected on May 24 were even fainter than that”, she said.</div> <div><br /></div> <div>This was new, strong evidence connecting fast radio bursts with magnetars, the scientists thought. Like more distant sources of fast radio bursts, SGR 1935+2154 seemed to be producing bursts at random intervals, and over a huge brightness range. </div> <div> </div> <div>“The brightest flashes from this magnetar are at least ten million times as bright as the faintest ones. We asked ourselves, could that also be true for fast radio burst sources outside our galaxy? If so, then the universe’s magnetars are creating beams of radio waves that could be criss-crossing the cosmos all the time – and many of these could be within the reach of modest-sized telescopes like ours”, said team member Jason Hessels (Anton Pannekoek Institute for Astronomy and ASTRON, Netherlands). </div> <div><br /></div> <img src="/SiteCollectionImages/Institutioner/SEE/Nyheter/sgr1935_futselaar_magnetar_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><div>Neutron stars are the tiny, extremely dense remnants left behind when a short-lived star of more than eight times the mass of the Sun explodes as a supernova. For 50 years, astronomers have studied pulsars, neutron stars which with clock-like regularity send out pulses of radio waves and other radiation. All pulsars are believed to have strong magnetic fields, but the magnetars are the strongest known magnets in the universe, each with a magnetic field hundreds of trillions of times stronger than the Sun’s.</div> <div><br /></div> <div>In the future, the team aims to keep the radio telescopes monitoring SGR 1935+2154 and other nearby magnetars, in the hope of pinning down how these extreme stars actually make their brief blasts of radiation. </div> <div><br /></div> <div>Scientists have presented many ideas for how fast radio bursts are generated. Franz Kirsten, astronomer at Onsala Space Observatory, Chalmers, who led the project, expects the rapid pace in understanding the physics behind fast radio bursts to continue.</div> <div><br /></div> <div>“The fireworks from this amazing, nearby magnetar have given us exciting clues about how fast radio bursts might be generated. The bursts we detected on May 24 could indicate a dramatic disturbance in the star’s magnetosphere, close to its surface. Other possible explanations, like shock waves further out from the magnetar, seem less likely, but I’d be delighted to be proved wrong. Whatever the answers, we can expect new measurements and new surprises in the months and years to come”, he said.</div> <div><br /></div> <div><a href="https://news.cision.com/chalmers/r/cosmic-flashes-come-in-all-different-sizes%2cc3237104">Read press release and access high-resolution images</a></div> <a href="https://news.cision.com/chalmers"> </a><div><br /></div> <div><strong>More about the research, the telescopes and Onsala Space Observatory</strong></div> <div><br /></div> <div>The research is published in a paper <em>Detection of two bright radio bursts from magnetar</em></div> <em> </em><div><em>SGR 1935+2154</em> in Nature Astronomy, by Franz Kirsten (Onsala Space Observatory, Chalmers), M. P. Snelders, M. Jenkins (Anton Pannekoek Institute for Astronomy, University of Amsterdam) K. Nimmo (Anton Pannekoek Institute for Astronomy, University of Amsterdam,  and ASTRON, Netherlands Institute for Radio Astronomy, Netherlands), J. van den Eijnden (Anton Pannekoek Institute for Astronomy, University of Amsterdam and Department of Physics, Astrophysics, University of Oxford), J. W. T. Hessels (Anton Pannekoek Institute for Astronomy, University of Amsterdam, and ASTRON, Netherlands Institute for Radio Astronomy, Netherlands), M. P. Gawroński (Institute of Astronomy, Nicolaus Copernicus University, Toruń, Poland) and Jun Yang (Onsala Space Observatory, Chalmers).</div> <div><br /></div> <div><span style="background-color:initial">Link to research paper in Nature Astronomy: </span><span style="background-color:initial"> <a href="https://www.nature.com/articles/s41550-020-01246-3">https://www.nature.com/articles/s41550-020-01246-3</a></span><br /></div> <div><span style="background-color:initial">The paper is also available at ArXiv: </span><span style="background-color:initial"><a href="https://arxiv.org/abs/2007.05101">https://a</a></span><span style="background-color:initial"><a href="https://arxiv.org/abs/2007.05101">rxiv.org/abs/2007.05101</a></span></div> <div><br /></div> <div><div>Franz Kirsten tells the story of the research project in an article &quot;Behind the paper: Hunting for Galactic counterparts to fast radio bursts​&quot; <span style="background-color:initial">at</span><span style="background-color:initial"> </span><span style="background-color:initial">Nature Astronomy Community:</span></div> <a style="outline:0px">https://astronomycommunity.nature.com/posts/hunting-for-galactic-counterparts-to-fast-radio-bursts</a></div> <div><br /></div> <img src="/SiteCollectionImages/Institutioner/SEE/Nyheter/onsala_20m_r_hammargren_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" /><div>The observations were carried out using the 25-metre RT1 telescope at Westerbork, Netherlands, both the 25-metre and 20-metre telescopes at Onsala Space Observatory, and the 32-metre telescope in Toruń, Poland. </div> <div><br /></div> <div>Onsala Space Observatory is Sweden's national facility for radio astronomy. The observatory provides researchers with equipment for the study of the earth and the rest of the universe. In Onsala, 45 km south of Gothenburg, it operates four radio telescopes and a station in the international telescope Lofar. It also participates in several international projects. The observatory is hosted by the Department of Space, Earth and Environment at Chalmers University of Technology, and is operated on behalf of the Swedish Research Council.</div> <div><br /></div> <div><strong>Contacts</strong></div> <div><br /></div> <div>Robert Cumming, communicator, Onsala Space Observatory, Chalmers, tel: +46 31-772 5500 or +46 70 493 3114, robert.cumming@chalmers.se.</div> <div> </div> <div>Franz Kirsten, astronomer, Onsala Space Observatory, Chalmers, +46 31-772 5532, franz.kirsten@chalmers.se</div> <div><br /></div> <div><strong><em>Images</em></strong></div> <div><strong><em><br /></em></strong></div> <div><em>A (top) On May 24, four European telescopes took part in the global effort to understand mysterious cosmic flashes. The telescopes captured flashes of radio waves from an extreme, magnetised star in our galaxy. All are shown in this illustration. </em></div> <div><em>Credit: </em><span style="background-color:initial"><em>Danielle Futselaar, </em><em><a href="http://artsource.nl/">artsource.nl</a></em></span></div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial"><em>B Artist's impression of the magnetar </em></span><span></span><span style="background-color:initial"><em>SGR 1935+2154.<br /></em></span><div><em>Credit: </em><span style="background-color:initial"><em>Danielle Futselaar, </em><em><a href="http://artsource.nl/">artsource.nl</a></em></span></div> <div><br /></div></div> <div><i>C Radio telescopes at Onsala Space Observatory in Sweden. Two of the telescopes at Onsala Space Observatory took part in observations of magnetar </i><i style="background-color:initial">SGR 1935+2154: the 20-metre telescope (in its protective radome) and 25-metre telescope (top right in the image). </i></div> <div><i>Foto: Chalmers/Magnus Falck</i><span style="background-color:initial"><br /></span></div> <div><br /></div> Mon, 16 Nov 2020 17:00:00 +0100https://www.chalmers.se/en/news/Pages/Star-hunt-at-swedish-schools.aspxhttps://www.chalmers.se/en/news/Pages/Star-hunt-at-swedish-schools.aspx​Star hunt at Swedish schools<p><b>​An intensive star hunt is currently ongoing at more than 20 Swedish schools –but it’s not any kind of talent show. It is this year's edition of the school project Help a Scientist, arranged for the tenth time by the Nobel Prize Museum. This year's theme is stars and space. The Star Hunt is a scientific search for new stars and a hunt for new knowledge about the conditions under which stars are formed.​</b></p><div><span style="background-color:initial"><br /></span></div> <img src="/SiteCollectionImages/Institutioner/SEE/Nyheter/Star-hunt-Giuliana_Ruben_Jonathan.jpg" class="chalmersPosition-FloatRight" alt="Portrait pictures Dr. Giuliana Cosentino, Dr. Rubén Fedriani and Professor Jonathan Tan" style="margin:5px" /><div><span style="background-color:initial">D</span><span style="background-color:initial">uring September, The Star Hunt has started at the participating schools, which are spread all over the country. 32 teachers and up to 1500 school children from 67 classes learn about astronomy and get to participate in a real research project. The students involved are in the eighth and ninth grades and they will get help from several Chalmers astronomers.</span><br /></div> <div><br /></div> <div>The researchers Dr. Giuliana Cosentino, Dr. Rubén Fedriani and Professor Jonathan Tan from Chalmers' Department of Space, Earth and Environment participate in this year's version of Help a Scientist. It is not only an exciting school project, but the students' results will be helpful to the researchers in their work.</div> <div><br /></div> <div>“Students will analyse images taken in a variety of wavelengths of light, from radio to x-ray, by telescopes in space, in the air and on the ground. The goal is to contribute new knowledge about the birth of stars and in the long run increase the understanding of our galaxy and our own origin”, says Jonathan Tan.<span style="background-color:initial"> </span></div> <h2 class="chalmersElement-H2">Image analysis in collaboration with NASA</h2> <div>What the students will help the researchers with is to identify new stars that are born from interstellar clouds and answer the questions if these stars form alone, as twins or clustered together in great broods?  </div> <div><br /></div> <div>The images the pupils will analyse will be provided by the web-based WorldWide Telescope platform, which interfaces with NASA databases.</div> <div><br /></div> <div>“We have worked with developers of this software specially for the Star Hunt project to upload some of our research datasets for the students to analyze. The students will be able to see for themselves how stars are forming in our galaxy by examining these images and cross matching them against a wide variety of other data available at the platform”, says Jonathan Tan.</div> <h2 class="chalmersElement-H2">Pilot exercises in the Gothenburg area</h2> <div>Earlier this year, pilot exercises were arranged at two different schools in the Gothenburg region, at Torslandaskolan and Torpskolan in Lerum.</div> <div><br /></div> <div>“We met the classes and gave a lecture on the formation of stars and how astronomers make observations with telescopes. Then we worked together on a research exercise. The test rounds were great for us; we have been able to develop the tasks and the tools based on the feedback we received from the students”, says Jonathan Tan.</div> <div><br /></div> <div>In addition to giving lectures for students, the researchers have worked hard to produce an 80-page booklet which explains the exercises. The document also contains an introduction to the subject of astronomy and to the research group's main focus, star formation.</div> <div><br /></div> <div>The researchers have also had a digital start-up conference with about thirty teachers and later this autumn, digital class visits will be done online.</div> <h2 class="chalmersElement-H2">Scientific level, creativity and design are awarded</h2> <div>Since the goal of Help a Scientist is to let the students experience a researcher's reality, they will also have to work on presenting their studies by making scientific posters that demonstrate the research process and the results from The Star Hunt. The posters are a part of a competition where different prizes are given based on science, creativity and design.</div> <div>​​<br /></div> <div>Each category has different jury groups consisting of researchers, science journalists and the pupils themselves. Students can win grants for their class funds and study visits to Chalmers where they get to meet prominent researchers.</div> <div><br /></div> <div>The winners will be presented in February 2021, hopefully at a ceremony at the Nobel Prize Museum in Stockholm.</div> <div><span style="background-color:initial"><br /></span></div> <div><span style="background-color:initial"><strong>Text:</strong> Julia Jansson​</span></div> Thu, 01 Oct 2020 14:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Exoplanets-and-Onsala-film-Day-and-Night-of-Astronomy-2020.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Exoplanets-and-Onsala-film-Day-and-Night-of-Astronomy-2020.aspxExoplanets and Onsala on film: Chalmers celebrates Sweden's Day and Night of Astronomy 2020<p><b>​Chalmers' exoplanet experts and a new film from Onsala Space Observatory are among the highlights at national festival Astronomins dag och natt 2020.</b></p>​Sweden's Day and Night of <span style="background-color:initial">Astronomy (Astronomins dag och natt) has theme &quot;Earth 2.0&quot; with a focus on exoplanets, and a program of events, both digital and in real life.</span><div><br /></div> <div>Chalmers astronomer Carina Persson is one of three invited speakers in the national digital program for the festival, to be broadcast on astronominsdag.se.</div> <div><br /></div> <div>Her colleagues Iskra Georgieva (Chalmers) and Oscar Barragán (University of Oxford) are also taking part in the digital program.</div> <div><br /></div> <div>A new film premieres showing Onsala Space Observatory and its telescopes as they have never been seen before. The five-minute short film <em>Onsala Space Observatory: aerial footage summer 2020</em>, by Roger Hammargren (Onsala Space Observatory), will be shown for the first time at 13:15 CEST during the festival Saturday.</div> <div><br /></div> <div>Times for festival events with connection to Chalmers on Saturday 26 September 2020:</div> <div><br /></div> <div><strong>11:35 Searching for Earth 2.0</strong></div> <div>Iskra Georgieva &amp; Oscar Barragán. Lecture in English. Broadcast on <a href="http://www.astronominsdag.se/live">astronominsdag.se/live</a> and then available at <a href="https://www.youtube.com/channel/UCHzFjhQKrOPD-5n-DBJKiyQ/">Astronomins dag och natt's YouTube channel</a> </div> <div><br /></div> <div><strong>12:30 An astronomical journey in space</strong></div> <div>Swedish cutting-edge research from the Wallenberg Foundation. Film from the Wallenberg Foundation in which the astronomer Kirsten Kraiberg Knudsen and the mathematician Robert Berman participate. The Swedish version is included at <a href="http://www.astronominsdag.se/live">astronominsdag.se/live</a> and is also available in English at </div> <div><a href="https://www.youtube.com/watch?v=aukLALQmd3w">https://www.youtube.com/watch?v=aukLALQmd3w</a></div> <div><br /></div> <div><div><span style="font-weight:700">13:10 </span><b><span style="background-color:initial"></span><span style="background-color:initial">Onsala Space Observatory: aerial footage summer 2020</span></b></div> <div>Film by Roger Hammargren, Chalmers. Broadcast on <a href="http://www.astronominsdag.se/live">astronominsdag.se/live</a> and available after that at <a href="https://youtu.be/i3QdQ2wCxhY">Onsala Space Observatory's YouTube channel.​</a></div></div> <div><br /></div> <div><strong>14:45 Exoplanets</strong></div> <div>Talk by Carina Persson. Broadcast on astronominsdag.se/live and available after that at <span></span><a href="https://www.youtube.com/channel/UCHzFjhQKrOPD-5n-DBJKiyQ/">Astronomins dag och natt's YouTube channel</a><span style="background-color:initial"> </span></div> <div><br /></div> <div>The festival's audio logo, seen and heard for the first time on September 24, also has a Chalmers connection. See it at YouTube at <a href="https://youtu.be/8FETAIC3-ac">https://youtu.be/8FETAIC3-ac</a></div> <div><br /></div> <div>The music is composed by Subramanyam Jaswanth, who did his Master's in radio astronomy at Chalmers in 2019 and whose thesis is the basis for a research article recently published in Astronomy and Astrophysics (<a href="https://doi.org/10.1051/0004-6361/202038978">https://doi.org/10.1051/0004-6361/202038978</a>).</div> <div><br /></div> <div><em>Images:</em></div> <div>A (top) Sweden's Day and Night of Astronomy: with plenty of exoplanets courtesy of (insets) Carina Persson and her colleagues Oscar Barragán and Iskra Georgieva, as well new aerial footage of Onsala Space Observatory.</div> <div>Sources: NASA Ames / JPL / T. Pyle (illustration); Chalmers and private (photos)</div> <div><br /></div> <div>B: Still picture from the short film <em>Onsala Space Observatory: aerial footage summer 2020</em> by Roger Hammargren. In the foreground is the round white radome that protects the observatory's 20-m telescope. All the observatory's telescopes can be seen in the film.</div> <div>Photo: Chalmers / R. Hammargren</div>Thu, 24 Sep 2020 15:00:00 +0200https://www.chalmers.se/en/departments/see/news/Pages/How-satellites-help-us-navigate.aspxhttps://www.chalmers.se/en/departments/see/news/Pages/How-satellites-help-us-navigate.aspxHow satellites help us navigate<p><b>​”Have you ever encountered a situation where you did not know exactly where you are? Somewhere in the middle of nowhere and with no idea where to go? Fortunately, there was your mobile phone nearby, your small, precious device. Soon you were able to find your way out, fix yourself some decent transport, get some food, and more. And all because of the Global Navigation Satellite System, a system which we use on a daily basis and for many different purposes.” With these words begins a new animated video that Grzegorz Klopotek, Ph.D. student at Onsala Space Observatory, has created. </b></p><p>Grzegorz works with radio telescopes and space geodesy, and among other things, technology for Onsala Space Observatory's Twin Telescopes. On April 17 he defends his doctoral dissertation. In the video he explains how satellites in space help us with navigation and positioning in everyday life. How can you use your cellphone to find your way home when you get lost? ​<br /></p> <p><br /></p> <p><span style="background-color:initial"><strong>Why did you produce this video? </strong></span><br /></p> <p><span style="background-color:initial"><br /></span></p> <p>- All Ph.D. students at Chalmers have to give a popular science presentation, before they can defend their thesis. Due to the Covid-19 outbreak, there was no possibility to prepare a normal presentation with an audience. So making a film that could reach the public sounded like a good alternative.</p> <p><br /></p> <p><strong>Who should watch the video and how can it be of use to them? </strong></p> <p><br /></p> <p><img src="/SiteCollectionImages/Institutioner/SEE/Nyheter/Greg-video-screenshot-280.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" />– In principle it’s for anyone who uses smartphones and who would like to know a bit more about how global navigation satellite systems work. It’s true that these systems are used most often for navigation, but they also have other applications, for example in land surveying or in Earth sciences. With the help of GNSS satellites in space, one can measure long-term changes in climate and environment, and their variation in time and space. </p> <p><br /></p> <p>At Onsala Space Observatory, Grzegorz and his colleagues study the shape, orientation and size of the Earth using space geodetic techniques such as GNSS. They also use geodetic very-long-baseline interferometry (VLBI), which involves observing radio waves from distant galaxies (so-called quasars) with networks of radio telescopes. Together with observations of geodetic satellites, these measurements can be used to study the Earth, and how its atmosphere, sea level and climate change over different timescales.</p> <p><br /></p> <p>– Space-geodetic techniques, such as GNSS and geodetic VLBI, provide us also with accurate and stable global reference frames. Those reference frames are needed in order to be able to measure, describe and quantify long-term changes in climate and the environment. You can say that with space-geodetic techniques we look deep into the sky in order to find out what’s beneath our feet.</p> <p><br /></p> <p>Besides navigation, the global satellite systems have many scientific applications, Grzegorz explains.</p> <p><br /></p> <p><img src="/SiteCollectionImages/Institutioner/SEE/Nyheter/Grzegorz.png" class="chalmersPosition-FloatRight" alt="" style="margin:5px" />– GNSS is used for instance to examine one of the Earth’s orientation parameters – so-called ’polar motion’ - and how the Earth’s shape is changing, for example movement of tectonic plates or land uplift. In Scandinavia, the biggest contribution to the land uplift comes from the phenomenon referred to as the post-glacial rebound. This effect is caused by the Earth’s crust returning to a mechanical resting state after being released from pressure from ice sheets during the last glacial period. With GNSS we can also study the atmosphere, particularly the troposphere and ionosphere. </p> <p><br /></p> <p>– At Onsala Space Observatory the technique called GNSS-R (GNSS-Reflectometry) is also used to determine sea-level height with few-centimeter-level precision. </p> <p><br /></p> <p><strong>In the video you mention that there will be even more applications for GNSS in the future. Which do you think will be the next applications we can expect? </strong></p> <p><br /></p> <p>– Autonomous driving could be the first and most obvious example. And in the near future, we can expect even better performance from GNSS for navigation purposes. </p> <p><br /></p> <p><strong>You will defend your Ph.D. thesis on April 17. What’s next for you? </strong></p> <p><br /></p> <p>– Probably research related not only to geodetic VLBI, but to space-geodetic techniques in general. A project concerning GNSS, satellite/lunar laser ranging and geodetic VLBI would sound good to me...</p> <p><br /></p> <p><a href="https://research.chalmers.se/publication/516075">Read Grzegorz’s thesis: Observations of Artificial Radio Sources within the Framework of Geodetic Very Long Baseline Interferometry here</a>. </p> <p><br /></p> <p>See <a href="https://www.youtube.com/watch?v=dEqSx6MOgnk">Grzegorz’s film Navigation in your hand on YouTube</a>, (subtitles are available in English and Swedish).</p> <p><br /></p>Thu, 16 Apr 2020 00:00:00 +0200https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/ALMA-reveals-an-aged-stars-metamorphosis-W43A.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/ALMA-reveals-an-aged-stars-metamorphosis-W43A.aspxALMA reveals an aged star’s metamorphosis<p><b>​An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (Alma) has captured the very moment when an old star first starts to alter its environment. The star has ejected high-speed, bipolar gas jets which are now colliding with the surrounding material; the age of the observed jet is estimated to be less than 60 years. These features help scientists understand how the complex shapes of planetary nebulae are formed.</b></p><div><div><span style="background-color:initial">Sun-like stars evolve to puffed-up red giants in the final stage of their lives. Then, the star expels gas to form a remnant called a planetary nebula. There is a wide variety in the shapes of planetary nebulae; some are spherical, but others are bipolar or show complicated structures. Astronomers are interested in the origins of this variety, but the thick dust and gas expelled by an old star obscure the system and make it difficult to investigate the inner-workings of the process.</span><br /></div> <div><br /></div> <div>To tackle this problem, a team of astronomers led by Daniel Tafoya at Chalmers University of Technology, Sweden, pointed Alma at W43A, an old star system about 7000 light years from Earth in the constellation Aquila, the Eagle.</div> <div><br /></div> <div><img src="/SiteCollectionImages/Centrum/Onsala%20rymdobservatorium/340x/20200305_W43A_composite_72dpi_340x340.jpg" class="chalmersPosition-FloatRight" alt="" style="margin:5px" />Thanks to Alma’s high resolution, the team obtained a very detailed view of the space around W43A. “The most notable structures are its small bipolar jets,” says Tafoya, the lead author of the research paper published by the Astrophysical Journal Letters. The team found that the velocity of the jets is as high as 175 km per second, which is much higher than previous estimations. Based on this speed and the size of the jets, the team calculated the age of the jets to be less than a human life-span.</div> <div><br /></div> <div>“Considering the youth of the jets compared to the overall lifetime of a star, it is safe to say we are witnessing the 'exact moment' that the jets have just started to shove through the surrounding gas,” explains Tafoya. “When the jets carve through the surrounding material in some 60 years, a single person can watch the progress in their life.”</div> <div><br /></div> <div>In fact, the Alma image clearly maps the distribution of dusty clouds entrained by the jets, which is telltale evidence that it is impacting on the surroundings.</div> <div><br /></div> <div>The team assumes that this entrainment is the key to form a bipolar-shaped planetary nebula. In their scenario, the aged star originally ejects gas spherically and the core of the star loses its envelope. If the star has a companion, gas from the companion pours onto the core of the dying star, and a portion of this new gas forms the jets. Therefore, whether or not the old star has a companion is an important factor to determine the structure of the resulting planetary nebula.</div> <div><br /></div> <div>“W43A is one of the peculiar so called ‘water fountain’ objects,” says Hiroshi Imai at Kagoshima University, Japan, a member of the team. “Some old stars show characteristic radio emissions from water molecules. We suppose that spots of these water emissions indicate the interface region between the jets and the surrounding material. We named them ‘water fountains,’ and it could be a sign that the central source is a binarity system launching a new jet.”</div> <div><br /></div> <div>“There are only 15 ‘water fountain’ objects identified to date, despite the fact that more than 100 billion stars are included in our Milky Way galaxy,” explains José Francisco Gómez, astronomer at Instituto de Astrofísica de Andalucía, Spain. “This is probably because the lifetime of the jets is quite short, so we are very lucky to see such rare objects.”</div></div> <div><br /></div> <div><div>Daniel Tafoya is looking forward to new insights on these remarkable stars, which are also similiar to our Sun.</div> <div><br /></div> <div>– We believe that these stars have a lot to tell us about what happens when stars like the Sun die. They give us new knowledge about why the sky's most beautiful objects, the planetary nebulae, look the way they do. They are also telling us about how stars like the Sun return material to the galaxy that can be part of the next generation of new stars, he says.</div></div> <div><br /></div> <div><strong>More about the research</strong></div> <div><br /></div> <div><span></span><div>These observation results were presented in D. Tafoya et al. “Shaping the envelope of the asymptotic giant branch star W43A with a collimated fast jet” published by the Astrophysical Journal Letters on February 13, 2020.</div> <div><br /></div> <div>The research team members are: <span style="background-color:initial">Daniel Tafoya (Chalmers University of Technology), Hiroshi Imai (Kagoshima University, Japan), José F. Gómez (Instituto de Astrofísica de Andalucía, CSIC), Jun-ichi Nakashima (Sun Yat-sen University, China), Gabor Orosz (University of Tasmania, Australia/Xinjiang Astronomical Observatory, China), and Bosco H. K. Yung (Nicolaus Copernicus Astronomical Center, Poland).</span></div></div> <div><br /></div> <div><br /></div> <div></div> <div><br /></div> <div><strong>Images</strong></div> <div><strong><br /></strong></div> <div>For high-resolution images, see the press release from NAOJ: <a href="https://www.nao.ac.jp/en/news/science/2020/20200305-alma.html">https://www.nao.ac.jp/en/news/science/2020/20200305-alma.html</a></div> <div><br /></div> <div><div><span style="background-color:initial"><em>A (top) - Artist’s impression of W43A based on the Alma observation results. Diffuse spherical gas was emitted from the star in the past. W43A has just started ejecting bipolar jets which entrain the surrounding material. Bright spots in radio emissions from water molecules are distributed around the interface of the jets and the diffuse gas.</em></span><br /></div> <div><em>Credit: NAOJ.</em></div></div> <div><br /></div> <div><div><em>B - Alma image of the old star system W43A. The high velocity bipolar jets ejected from the central aged star are seen in blue, low velocity outflow is shown in green, and dusty clouds entrained by the jets are shown in orange.</em></div> <div><em>Credit: ALMA (ESO/NAOJ/NRAO), Tafoya et al.</em></div></div> <div><br /></div> <div><strong>Contacts:</strong></div> <div><div> </div> <div>Robert Cumming, communicator, Onsala Space Observatory, Chalmers, 031-772 5500, 070-493 31 14, robert.cumming@chalmers.se</div> <div><br /></div> <div>Daniel Tafoya, astronomer, Onsala S<span style="background-color:initial">pace Observatory</span><span style="background-color:initial">, Chalmers, 031 772 5519, daniel.tafoya@chalmers.se</span></div> <em></em></div> <div><br /></div>Thu, 05 Mar 2020 07:00:00 +0100https://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Alma-double-star-HD101584.aspxhttps://www.chalmers.se/en/researchinfrastructure/oso/news/Pages/Alma-double-star-HD101584.aspxChalmers astronomers and Alma study stellar fight's beautiful outcome<p><b>​A Chalmers-led team of ​astronomers have used the telescope Alma to study the remarkable gas cloud that resulted from a confrontation between two stars. One star grew so large it engulfed the other which, in turn, spiralled towards its partner provoking it into shedding its outer layers.</b></p><div><span style="background-color:initial">Like humans, stars change with age and ultimately die. For the Sun and stars like it, this change will take it through a phase where, having burned all the hydrogen in its core, it swells up into a large and bright red-giant star. Eventually, the dying Sun will lose its outer layers, leaving behind its core: a hot and dense star called a white dwarf.</span><br /></div> <div><br /></div> <div>“The star system HD101584 is special in the sense that this ‘death process’ was terminated prematurely and dramatically as a nearby low-mass companion star was engulfed by the giant,” said Hans Olofsson, astronomer at Chalmers University of Technology, who led a recent study, published in Astronomy &amp; Astrophysics, of this intriguing object.</div> <div><br /></div> <div>Thanks to new observations with Alma, complemented by data from the telescope Apex (Atacama Pathfinder EXperiment), Hans Olofsson and his team now know that what happened in the double-star system HD 101584 was akin to a stellar fight. As the main star puffed up into a red giant, it grew large enough to swallow its lower-mass partner. In response, the smaller star spiralled in towards the giant’s core but didn’t collide with it. Rather, this manoeuvre triggered the larger star into an outburst, leaving its gas layers dramatically scattered and its core exposed.</div> <div><br /></div> <div>The team says the complex structure of the gas in the HD101584 nebula is due to the smaller star’s spiralling towards the red giant, as well as to the jets of gas that formed in this process. As a deadly blow to the already defeated gas layers, these jets blasted through the previously ejected material, forming the rings of gas and the bright bluish and reddish blobs seen in the nebula.</div> <div><br /></div> <div>A silver lining of a stellar fight is that it helps astronomers to better understand the final evolution of stars like the Sun, explains co-author Sofia Ramstedt, astronomer at Uppsala University.</div> <div><br /></div> <div>“Currently, we can describe the death processes common to many Sun-like stars, but we cannot explain why or exactly how they happen. HD101584 gives us important clues to solve this puzzle since it is currently in a short transitional phase between better studied evolutionary stages. With detailed images of the environment of HD101584 we can make the connection between the giant star it was before, and the stellar remnant it will soon become,” she says.</div> <div><br /></div> <div>Co-author Elizabeth Humphreys from ESO in Chile highlighted that Alma and Apex, located in the country’s Atacama region, were crucial to enabling the team to probe “both the physics and chemistry in action” in the gas cloud. She added: “This stunning image of the circumstellar environment of HD 101584 would not have been possible without the exquisite sensitivity and angular resolution provided by Alma.”</div> <div><br /></div> <div>While current telescopes allow astronomers to study the gas around the binary, the two stars at the centre of the complex nebula are too close together and too far away to be resolved. ESO’s Extremely Large Telescope, under construction in Chile’s Atacama Desert, “will provide information on the ‘heart’ of the object,” says Hans Olofsson, allowing astronomers a closer look at the fighting pair. </div> <div><br /></div> <div>See also ESO's press release: <a href="https://www.eso.org/public/news/eso2002/">https://www.eso.org/public/news/eso2002/</a></div> <div><br /></div> <div><strong><em>Image:</em></strong></div> <em> </em><div><br /></div> <em> </em><div><em>A. (top) </em><span style="background-color:initial"><em>​ALMA reveals the beautiful results of a struggle between two stars: a complex of gas clouds round binary star HD 101584. </em></span><span style="background-color:initial"><em>​</em></span><span style="background-color:initial"><em> The colours represent speed, going from blue — gas moving the fastest towards us — to red — gas moving the fastest away from us. Jets, almost along the line of sight, propel the material in blue and red. The stars in the binary are located at the single bright dot at the centre of the ring-like structure shown in green, which is moving with the same velocity as the system as a whole along the line of sight. Astronomers believe this ring has its origin in the material ejected as the lower mass star in the binary spiralled towards its red-giant partner.​</em></span></div> <em> </em><div><span style="background-color:initial"><em>Credit: </em></span><span style="background-color:initial"><em>ALMA (ESO/NAOJ/NRAO), Olofsson et al. Acknowledgement: Robert Cumming</em></span></div> <em> </em><div><br /></div> <div><strong>More information</strong></div> <div><br /></div> <div>This research was presented in a paper published in Astronomy &amp; Astrophysics: <i style="background-color:initial">HD 101584: circumstellar characteristics and evolutionary status</i><span style="background-color:initial"> </span><span style="background-color:initial">(</span><a href="https://doi.org/10.1051/0004-6361/201834897">https://doi.org/10.1051/0004-6361/201834897</a><span style="background-color:initial">)</span></div> <div><br /></div> <div>The team is composed of Hans Olofsson (Department of Space, Earth and Environment, Chalmers), Theo Khouri (Chalmers), Matthias Maercker (Chalmers), Per Bergman (Chalmers), Lam Doan (Department of Physics and Astronomy, Uppsala University), Daniel Tafoya (National Astronomical Observatory of Japan and Onsala Space Observatory, Chalmers), Wouter Vlemmings (Chalmers), E. M. L. Humphreys (European Southern Observatory [ESO], Garching, Germany), Michael Lindqvist (<span style="background-color:initial">Onsala Space Observatory,</span><span style="background-color:initial"> </span><span style="background-color:initial">Chal</span><span style="background-color:initial">mers), Lars-Åke Nyman (ESO, Santiago, Chile) and Sofia Ramstedt (Uppsala University).</span></div> <div></div> <div><br /></div> <div>The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI). ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA. </div> <div><br /></div> <div>Chalmers and Onsala Space Observatory have been involved in Alma since its inception, building for example receivers for the telescope. Onsala Space Observatory hosts the Nordic Alma Regional Centre which provides technical expertise and supports scientists <span style="background-color:initial">in the Nordic countries who </span><span style="background-color:initial">use​​​​​ Alma</span><span style="background-color:initial">.​</span></div> <span></span><div></div> <div><br /></div>Wed, 05 Feb 2020 00:00:00 +0100https://www.chalmers.se/en/departments/see/news/Pages/Cheops-satellite-exoplanets-detail.aspxhttps://www.chalmers.se/en/departments/see/news/Pages/Cheops-satellite-exoplanets-detail.aspxCheops: new satellite to study exoplanets in detail<p><b>​​The satellite CHEOPS, launched in December 2019, will observe systems with previously known exoplanets – planets which orbit other stars than the sun – in order that we can learn more about their size, composition, and atmosphere. The project is led by Nobel laureate Didier Queloz, who will visit Chalmers on 13 December.</b></p>​<span style="background-color:initial">At Chalmers, Carina Persson and her colleagues are preparing to receive and analyse the huge amounts of data that the satellite will deliver. </span><div><br /> </div> <div>“We previously believed that all systems looked more or less like ours. But the first exoplanet found by Queloz and Mayor was a Jupiter-like planet, that orbits so close to its star that its orbital period is only four days – which was very surprising,” says astronomer Carina Persson.</div> <div><br /> </div> <div>“CHEOPS will take us a step closer to answering whether our planetary system is unique in the universe. Perhaps it is really uncommon for a medium size planet such as ours to form, at just the right distance, from a star of just the right type, with the right sorts of planets around, and in the right place in the galaxy.”</div> <div><br /> </div> <div>There are two main techniques for finding and studying exoplanets. The technique which was awarded the 2019 Nobel Prize measures small, regular changes in a star’s speed, which can be measured from Earth when a planet orbits the star. The technique has been used to discover many planets, and researchers can derive information on a planet’s mass, and distance from its host star. </div> <div><br /> </div> <div>The CHEOPS satellite will use another technique, transit photometry, to observe how a star’s light changes </div> <div>when a planet passes in front of it.  </div> <div><br /> </div> <div><span style="background-color:initial"><img class="chalmersPosition-FloatRight" src="/SiteCollectionImages/Institutioner/SEE/Nyheter/Carina_Malcolm_Iskra.jpg" alt="" style="margin:5px" />“The advantage with CHEOPS is that we already know which planets it will investigate, and what their orbits look like. So, we know exactly where and when we should point the telescope, in order to capture several transits from the same planet,” says Carina Persson, who works closely together with colleagues Professor Malcolm Fridlund and PhD Student Iskra Georgieva.</span></div> <div><br /> </div> <div>“In general, measurements like this which have been made so far have come with large uncertainties. With CHEOPS, the precision will increase significantly. We will be able to measure the planet’s size with high accuracy, look for moons and rings and maybe even draw conclusions about what kind of atmosphere they have. If we add that to what we already know about them, we can make models of the planets’ compositions to find out if they are Earth-like or gas planets. The results can also be used to model how planets form and evolve.”</div> <div><br /> </div> <div>The three Chalmers scientists have tested and developed software with algorithms which will analyse transiting exoplanets recorded in CHEOPS’ measurements. </div> <div><br /> </div> <div>“There are so many factors that decide how planets form, and so far, we only know of one planet which supports life. The more you study other planets, the more respect you feel for our planet and life on Earth. I think that is one of the most important aspects of our work,” says Carina Persson.  </div> <div>​<br /></div> <div><i>Text: Christian Löwhagen</i></div> <div><i>This article was originally published in Swedish in <a href="/sv/nyheter/magasin/Sidor/default.aspx">Chalmers magasin</a>, 2019 nr 2. </i></div> Tue, 10 Dec 2019 00:00:00 +0100