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  • richardmitnick 3:48 pm on March 28, 2021 Permalink | Reply
    Tags: "Who’s who on the ELT - Part III", , , , ESO - European Southern Observatory, ,   

    From ESOblog (EU): “Who’s who on the ELT – Part III” 

    ESO 50 Large

    From ESOblog (EU)

    26 March 2021
    People@ESO

    Bigger than all existing optical research telescopes combined, ESO’s Extremely Large Telescope (ELT) will drive astronomy into the future, tackling the biggest scientific challenges of our time. But to construct such an innovative and powerful telescope, it takes many different people working in an enormous variety of roles. In this series of blog posts, we hear from some of the people working on the ELT, exploring the work they do to help us reach the stars.

    Emanuela Ciattaglia (ELT Assembly, Integration and Verification Manager)

    “Since the end of 2016, I have been leading a great, expert team in planning the Assembly, Integration and Verification phase of the ELT on site. This is when all telescope subsystems are assembled together for the first time, and the telescope is finally “switched on” and tuned to get ready to bring distant objects closer to us.

    Since I was a child, I’ve been fascinated with how everything works and kept following my dad repairing cars and things around the house. Studying mechanical engineering meant my fascination finally found some solid explanations in understanding how things can be put together to achieve a function.

    Before the ELT, I worked on ALMA. My first visit to the ALMA site, high up on the Chajnantor plateau, felt like being on another planet, and yet the antennas we had worked on for so long were right there, moving together beautifully.

    Now, I really enjoy that my work on the ELT gives me a wide overview of the first part of the telescope’s life on site: from the arrival of various components, to their assembly and testing, until they are all serving their special functions together in this fantastic machine. Currently, my work days are full of meetings with the team, and the many teams we interface with, to plan the work on site. It is pretty dynamic, with numerous exchanges on many different topics, challenging at times but extremely interesting!

    A very memorable moment was back in 2016: being on the flattened top of Cerro Armazones for the first time was thrilling! I walked across it, thinking about how the work of ESO, all the contractors across many countries and everyone supporting us would one day materialise into a gigantic telescope on that exact soil. In the future, we will be back on that mountain top with so much more experience (and grey hair!), and able to admire the result of all our amazing work.

    Outside work, my family lovingly fills my time. We love trying out different sports together and repairing our cars and bikes. When I have the time, I like playing piano, painting and learning about neuroscience discoveries.”

    Lorenzo Pettazzi (Control Engineer)

    “When you are an engineer any moment you spend in the field is a memorable one, because it very often represents a big step in your personal “learning curve”. ESO’s Paranal Observatory is a very special place where engineers and astronomers are learning every day how to push the limits of technology to refine the art of astronomical observation and expand our knowledge of the Universe. We can use our knowledge and experience from building and operating the VLT at Paranal Observatory in constructing the ELT at Cerro Armazones.

    My fascination with space exploration drew me to study aerospace engineering at the age of 18. Now as a control engineer for the ELT, I am involved in designing and building the devices necessary to move the giant optical elements of the telescope. In particular I am the Workpackage Manager for the M1 Position Actuators, which will control the fine motions of each of the 798 segments of the ELT’s main mirror. The complexity of the projects means my work days are always different! Sometimes I spend the day in the lab testing future ELT actuators, other times I work at my computer simulating the performance of the telescope’s algorithms. I also coordinate the work of colleagues or external contractors to complete these projects. I enjoy working side by side with very talented professionals on the development of cutting edge technologies. The idea of building a unique facility which will shape future astronomical research always keeps me motivated.

    When I am not working at ESO, I enjoy sports including tennis, football, snowboarding and jogging. I sometimes relax by practising my juggling skills, reading comics or taking part in outdoor activities with my family. Last but not least, I am an enthusiastic supporter of AS Roma, the football team of my hometown!”

    Juan Carlos Palacio (Mechanical Construction Engineer)

    “Growing up, there wasn’t much to do in the village I lived in in southern Chile — no internet or video games and it rained all winter, so I spent my time trying to understand physical processes and playing with numbers to solve equations. After high school, I started to study engineering, which narrowed down to mechanical engineering after I was delighted by all of the thermal processes and fluid mechanics in a course of thermodynamics.

    I am now a mechanical construction engineer, which involves participating in technical reviews for the ELT’s dome and main structure and other subsystems. A typical day is spent reviewing mechanical designs and calculations in documentation delivered by contractors, as well as revising the maintainability and reliability of equipment; this is very important to ensure that the time the ELT spends on-sky collecting data for astronomical research is maximised. After working on the VLT at Paranal Observatory for 15 years, I am trying to transfer the experience I gained by contributing information about the typical issues we have faced with the VLT.

    For me, the most remarkable part of the ELT project so far was seeing the first design of the dome rotation mechanism. We have developed this to be able to hold and rotate the telescope’s dome, which will have a mass of more than 6100 tonnes! Participating in meetings with contractors and evaluating their designs is an enjoyable learning process because they bring new ideas that they have implemented in projects in totally different sectors, which opens our minds to investigate whether such technology could be useful for the ELT.”

    Alain Delorme (Contracts and Procurement Officer)

    “My educational background is in economics, and I started working in a sales department. Then one day I had an opportunity to switch to the other side, the purchasing part, first in a commercial business then for the French Ministry of Defence, where I processed the procurement part of high-technology equipment. And I just loved it! When I applied to ESO, the organisation was looking for an engineer with some procurement experience. Instead, I offered strong procurement experience in technological areas.

    Even though I’m not an engineer, I enjoy the technological side of my work. I like to understand what I’m working on, not only my part — the procurement process and commercial and contractual aspects — but also the technical issues, constraints and implications, hence I appreciate the discussions with my colleagues in charge of the technical aspects of the project I am involved in. I also very much like having to deal with a variety of issues and areas. The ELT offers all of that.

    I was specifically recruited in 2010 for the ELT. Although my tasks extend beyond that project, I am heavily involved in ELT procurements since it represents a significant part of our activities. Currently, I am in charge of many of the commercial aspects of the ELT’s different mirrors, including their polishing, coating and washing — the mirrors are very complex so this is a surprisingly large amount of work! My job consists mainly of processing recurring tasks and procurements of systems which usually conclude after a long tendering process. In all cases, I am happy when I consider the outcome of a process satisfactory for ESO. There is a mixture of small and bigger satisfactions. Of course when you witness important milestones of a contract (for example the first blasting of Cerro Armazones), or conclude a negotiation after a process which is complex (the polishing of the primary mirror) or difficult (the edge sensors), these are memorable moments!”

    Elise Vernet (Adaptive Optics Expert)

    “As a teenager, I was an amateur astronomer and built a small Dobsonian telescope, which led me to studying physics at university. In my last year, I specialised in high angular resolution astronomy, which introduced me to adaptive optics systems, an essential technology to achieve sharper images. It was in 1997 and ESO’s 3.6-metre telescope at La Silla Observatory was just providing its first results using this technology. I found it amazing that we could overcome the effects of the atmosphere, using very fast mirrors and sensors to get higher resolution images as if we were observing from space rather than from the ground.

    Now, I continue to work with adaptive optics systems on the ELT. I am responsible for two of the ELT’s five mirrors: the adaptive M4 mirror and the ultralight weight M5 mirror. These two critical subunits are designed and manufactured by external companies, so on a typical day I follow up on the projects, read documents and attend meetings with the companies to try help solve technical issues and find out any risks which could delay the project or increase its cost. As some components of both subunits are already being manufactured and assembled, I am also verifying they meet requirements.

    I really enjoy following up on state-of-the-art projects like the ELT. I do my best to get the very technologically challenging components delivered to specification and on time. I like that every day I’m improving my technical knowledge on aspects of manufacturing and integration, and I enjoy helping test and inspect each subsystem. The most memorable moment in my career so far was back when I was working on the VLT. Installing the deformable secondary mirror on the VLT’s Unit Telescope 4 to provide images corrected for atmospheric effects, gave a second life to the telescope.

    Outside of work, I like making clothes for my whole family. I also have a lot of fun cooking international recipes and visiting foreign countries.”

    Mark Wallace (Expert Control System Engineer)

    “My role involves developing the Interlock and Safety System, which covers the safety interactions of all ELT subsystems to keep both people and the equipment safe. For example, ensuring that the lasers cannot be switched on if people are inside the dome to avoid exposing them to potentially harmful radiation or ensuring that the altitude structure (telescope tube) cannot move while M1 segments are being exchanged to protect the people and mirror segments involved. A typical day involves writing or reviewing design reports and technical memos, testing various hardware configurations and the odd meeting.

    What I enjoy most about my work is being challenged by unusual problems and learning new things. The juxtaposition of the sheer size of the ELT, the requirements on accuracy and precision, and the harsh range of environmental conditions on Cerro Armazones creates myriad challenges. Talking to and working with others at ESO provides plenty of opportunities to learn from their experience.

    I have always enjoyed solving puzzles and in high school, I saw that a career in engineering meant solving real-world problems. I was set on aeronautical engineering, even applying to the Australian Defence Force Academy. In the end, I opted for mechatronics engineering to defer choosing my specialty. Taking mechatronics gave me the opportunity to work on a variety of machines, including making Joint Strike Fighter components. The experience I gained in motion control and functional safety in industry led to my involvement in the ELT.

    A highlight in my career was prototyping large-scale 3D printing combined with 5-axis machining to print large structures quickly and accurately. The tough requirements made every step towards success more rewarding. For the ELT, seeing the site first-hand gave me a better feeling of the project’s enormity than drawings or 3D models ever could.

    Outside work, we recently got a puppy. Meeting other dogs (and their owners) in the park allows me to practice German. I also like skiing and sledding with my kids. My colleagues may not know, but I used to row competitively and if I could find time here in Munich, I would love to get back into it.”

    Fabio Biancat Marchet (Programme Engineer)

    “From the mist of my early memories, I can distinguish the blurred image of that first “small step for man” on an alien world, which probably inspired my future. As a child, I was attracted by the complexity of systems, by the interactions between them and by their intrinsic mechanisms and the possibility of creating new ones.

    I started working for the ELT in 2017 as the Programme Engineer. My duty is mainly to coordinate the efforts of a number of experts and I spend my days communicating with colleagues and contractors or reviewing documentation. What makes this job challenging is the fact that often decisions have to be made relying on partial information and compromises have to be found among conflicting constraints.

    Besides the obvious pride of contributing to one of the biggest scientific enterprises ever, what gratifies me most is the productive interaction with people and feeling part of a team that shares a common objective; where everyone contributes with their own unique skills, background, character and culture. I’m convinced that, whether you’re building advanced astronomical facilities, cars, or washing machines, this is what really enriches you.

    For me, engineering should involve working towards a higher respect for the environment. Visiting the ELT construction site for the first time was a breathtaking experience, and not just because of the over 3000-metre elevation; only there looking at the huge hole in the mountain can one grasp the true breadth of the project. And the depth of that scar reminds us of our responsibility to develop not yet another monument to the arrogance of mankind, but rather a sign of its thirst for knowledge.

    To take my mind off work and relieve the stress, I like to cook, which I find simultaneously challenging and relaxing. And after all, cooking has a lot in common with being an ELT engineer; it requires ingenuity, planning, staying within a budget and schedule, and — most importantly — satisfying customers.”

    Amelie Gnatz (Document Controller)

    “As the ELT Document Controller, I am responsible for keeping the ELT document repository updated and the ELT documents accessible to the authorised users. My goal is to support the ELT staff with documentation matters and ensure the accuracy, quality and integrity of the ELT documents. In cooperation with the project managers and the managers responsible for the different components of the ELT, I take care of the documents delivered by external parties for reviews and prepare documentation packages for procurements. As part of the Systems Engineering Team I am involved in configuration management processes ensuring that the system will perform as intended, and is identified and documented in sufficient detail.

    While documentation is a topic that tends to be overlooked, it plays a key role in each and every project and at each stage of the project. Having in place a well-maintained repository ensures a common source of truth to work with and enables the project to evolve smoothly. Long story short, the ELT repository has the aim to make our lives at the ELT easier.

    The ELT is an unique and complex project that is evolving fast. The repository structure and how we manage the processes of documentation and configuration management need to be constantly adjusted according to the project’s evolution. This makes my role very varied and interesting. Aside from my day-to-day work in Garching, I will never forget my trips to Chile, where I had the chance to see Cerro Armazones — the new ELT site — after the mountain plateau was created. But I think the most memorable moment is yet to come: seeing the complete ELT for the first time.”

    See the full article here .


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    European Southern Observatory(EU) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ) •KUEYEN (UT2; The Moon ) •MELIPAL (UT3; The Southern Cross ), and •YEPUN (UT4; Venus – as evening star). Elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    Part of ESO’s Paranal Observatory, the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light at an elevation of 2,635 metres (8,645 ft) above sea level.

    European Southern Observatory(EU)/MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) ESO’s Atacama Pathfinder Experiment(CL) high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at ESO Cerro Paranal site. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

     
  • richardmitnick 11:57 am on December 10, 2020 Permalink | Reply
    Tags: "Hubble Pins Down Weird Exoplanet with Far-Flung Orbit", A planet in an unlikely orbit around a double star 336 light-years away may offer a clue to a mystery much closer to home: a hypothesized distant body in our solar system dubbed "Planet Nine.", , , , , ESO - European Southern Observatory, , , The 11-Jupiter-mass exoplanet called HD 106906 b,   

    From NASA/ESA Hubble Telescope: “Hubble Pins Down Weird Exoplanet with Far-Flung Orbit” 

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    December 10, 2020

    Media Contacts:
    Ann Jenkins
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4488
    jenkins@stsci.edu

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    Science Contacts:
    Meiji Nguyen
    University of California, Berkeley, California
    meiji274@berkeley.edu

    Robert De Rosa
    European Southern Observatory, Santiago, Chile
    rderosa@eso.org

    Paul Kalas
    University of California, Berkeley, California
    kalas@berkeley.edu

    1
    About This Image
    This Hubble Space Telescope image shows one possible orbit (dashed ellipse) of the 11-Jupiter-mass exoplanet HD 106906 b. This remote world is widely separated from its host stars, whose brilliant light is masked here to allow the planet to be seen. The planet resides outside its system’s circumstellar debris disk, which is akin to our own Kuiper Belt of small, icy bodies beyond Neptune. The disk itself is asymmetric and distorted, perhaps due to the gravitational tug of the wayward planet. Other points of light in the image are background stars.
    Credit: NASA, ESA, M. Nguyen (University of California, Berkeley), R. De Rosa (European Southern Observatory), and P. Kalas (University of California, Berkeley and SETI Institute)

    2
    About This Image
    The 11-Jupiter-mass exoplanet called HD 106906 b, shown in this artist’s illustration, occupies an unlikely orbit around a double star 336 light-years away. It may be offering clues to something that might be much closer to home: a hypothesized distant member of our solar system dubbed “Planet Nine.” This is the first time that astronomers have been able to measure the motion of a massive Jupiter-like planet that is orbiting very far away from its host stars and visible debris disk. Credit: NASA, ESA, M. Kornmesser (ESA/Hubble).

    3
    About This Image
    This graphic shows how the exoplanet HD 106906 b may have evolved over time, arriving at its current, widely separated, eccentric and highly misaligned orbit. (1) The planet formed much closer to its stars, inside a circumstellar disk of gas and dust. Drag from the disk caused the planet’s orbit to decay, forcing it to spiral inward toward its stellar pair. (2) The gravitational effects from the host stars then kicked the planet out onto an unstable orbit that almost threw it out of the system and into the void of interstellar space. (3) A passing star from outside the system stabilized HD 106906 b’s orbit and prevented the planet from leaving its home system. Credit: NASA,ESA, and L. Hustak STSCI.

    4
    About This Image
    This Hubble Space Telescope image shows the environment around double star HD 106906. The brilliant light from these stars is masked here to allow fainter features in the system to be seen. The stars’ circumstellar disk is asymmetric and distorted, perhaps due to the gravitational tug of the wayward planet HD 106906 b, which is in a very large and elongated orbit. Credit:
    NASA, ESA, M. Nguyen (University of California, Berkeley), R. De Rosa (European Southern Observatory), and P. Kalas (University of California, Berkeley and SETI Institute).


    About This Video
    This video shows the possible orbit of exoplanet HD 106906 b. The light from the twin stars has been masked to block their bright glare, allowing the Hubble Space Telescope to see the circumstellar disk and exoplanet. The planet resides outside its system’s circumstellar debris disk, which is akin to our own Kuiper Belt. The second part of the video shows a simulation of how the planet orbits counterclockwise around the entire system as seen from Earth. Credit: NASA, ESA, P. Kalas (University of California, Berkeley and SETI Institute), and J. DePasquale (STScI).

    A planet in an unlikely orbit around a double star 336 light-years away may offer a clue to a mystery much closer to home: a hypothesized, distant body in our solar system dubbed “Planet Nine.”

    This is the first time that astronomers have been able to measure the motion of a massive Jupiter-like planet that is orbiting very far away from its host stars and visible debris disk. This disk is similar to our Kuiper Belt of small, icy bodies beyond Neptune. In our own solar system, the suspected Planet Nine would also lie far outside of the Kuiper Belt on a similarly strange orbit. Though the search for a Planet Nine continues, this exoplanet discovery is evidence that such oddball orbits are possible.

    “This system draws a potentially unique comparison with our solar system,” explained the paper’s lead author, Meiji Nguyen of the University of California, Berkeley. “It’s very widely separated from its host stars on an eccentric and highly misaligned orbit, just like the prediction for Planet Nine. This begs the question of how these planets formed and evolved to end up in their current configuration.”

    The system where this gas giant resides is only 15 million years old. This suggests that our Planet Nine—if it does exist—could have formed very early on in the evolution of our 4.6-billion-year-old solar system.

    An Extreme Orbit

    The 11-Jupiter-mass exoplanet called HD 106906 b was discovered in 2013 with the Magellan Telescopes at the Las Campanas Observatory in the Atacama Desert of Chile.

    Carnegie 6.5 meter Magellan Baade and Clay Telescopes located at Carnegie’s Las Campanas Observatory, Chile. over 2,500 m (8,200 ft) high.

    However, astronomers did not know anything about the planet’s orbit. This required something only the Hubble Space Telescope could do: collect very accurate measurements of the vagabond’s motion over 14 years with extraordinary precision. The team used data from the Hubble archive that provided evidence for this motion.

    The exoplanet resides extremely far from its host pair of bright, young stars—more than 730 times the distance of the Earth from the Sun, or nearly 6.8 billion miles. This wide separation made it enormously challenging to determine the 15,000-year-long orbit in such a relatively short time span of Hubble observations. The planet is creeping very slowly along its orbit, given the weak gravitational pull of its very distant parent stars.

    The Hubble team was surprised to find that the remote world has an extreme orbit that is very misaligned, elongated and external to the debris disk that surrounds the exoplanet’s twin host stars. The debris disk itself is very unusual-looking, perhaps due to the gravitational tug of the wayward planet.

    How Did It Get There?

    So how did the exoplanet arrive at such a distant and strangely inclined orbit? The prevailing theory is that it formed much closer to its stars, about three times the distance that the Earth is from the Sun. But drag within the system’s gas disk caused the planet’s orbit to decay, forcing it to migrate inward toward its stellar pair. The gravitational effects from the whirling twin stars then kicked it out onto an eccentric orbit that almost threw it out of the system and into the void of interstellar space. Then a passing star from outside the system stabilized the exoplanet’s orbit and prevented it from leaving its home system.

    Using precise distance and motion measurements from the European Space Agency’s Gaia survey satellite, candidate passing stars were identified in 2019 by team members Robert De Rosa of the European Southern Observatory in Santiago, Chile and Paul Kalas of the University of California.

    ESA (EU)/GAIA satellite .

    A Messy Disk

    In a study published in 2015, Kalas led a team that found circumstantial evidence for the runaway planet’s behavior: the system’s debris disk is strongly asymmetric, rather than being a circular “pizza pie” distribution of material. One side of the disk is truncated relative to the opposite side, and it is also disturbed vertically rather than being restricted to a narrow plane as seen on the opposite side of the stars.

    “The idea is that every time the planet comes to its closest approach to the binary star, it stirs up the material in the disk,” explains De Rosa. “So every time the planet comes through, it truncates the disk and pushes it up on one side. This scenario has been tested with simulations of this system with the planet on a similar orbit—this was before we knew what the orbit of the planet was.”

    “It’s like arriving at the scene of a car crash, and you’re trying to reconstruct what happened,” explained Kalas. “Is it passing stars that perturbed the planet, then the planet perturbed the disk? Is it the binary in the middle that first perturbed the planet, and then it perturbed the disk? Or did passing stars disturb both the planet and disk at the same time? This is astronomy detective work, gathering the evidence we need to come up with some plausible storylines about what happened here.”

    A Planet Nine Proxy?

    This scenario for HD 106906 b’s bizarre orbit is similar in some ways to what may have caused the hypothetical Planet Nine to end up in the outer reaches of our own solar system, well beyond the orbit of the other planets and beyond the Kuiper Belt.

    Kuiper Belt. Minor Planet Center

    Planet Nine could have formed in the inner solar system and been kicked out by interactions with Jupiter. However, Jupiter—the proverbial 800-pound gorilla in our solar system—would very likely have flung Planet Nine far beyond Pluto. Passing stars may have stabilized the orbit of the kicked-out planet by pushing the orbit path away from Jupiter and the other planets in the inner solar system.

    “It’s as if we have a time machine for our own planetary system going back 4.6 billion years to see what may have happened when our young solar system was dynamically active and everything was being jostled around and rearranged,” said Kalas.

    To date, astronomers only have circumstantial evidence for Planet Nine. They’ve found a cluster of small celestial bodies beyond Neptune that move in unusual orbits compared with the rest of the solar system. This configuration, some astronomers say, suggests these objects were shepherded together by the gravitational pull of a huge, unseen planet. An alternative theory is that there is not one giant perturbing planet, but instead the imbalance is due to the combined gravitational influence of multiple, much smaller objects. Another theory is that Planet Nine does not exist at all and the clustering of smaller bodies may be just a statistical anomaly.

    A Target for the Webb Telescope

    Scientists using NASA’s upcoming James Webb Space Telescope plan to get data on HD 106906 b to understand the planet in detail.

    NASA James Webb Space Telescope annotated.

    “One question you could ask is: Does the planet have its own debris system around it? Does it capture material every time it goes close to the host stars? And you’d be able to measure that with the thermal infrared data from Webb,” said De Rosa. “Also, in terms of helping to understand the orbit, I think Webb would be useful for helping to confirm our result.”

    Because Webb is sensitive to smaller, Saturn-mass planets, it may be able to detect other exoplanets that have been ejected from this and other inner planetary systems. “With Webb, we can start to look for planets that are both a little bit older and a little bit fainter,” explained Nguyen. The unique sensitivity and imaging capabilities of Webb will open up new possibilities for detecting and studying these unconventional planets and systems.

    The team’s findings appear in the December 10, 2020 edition of The Astronomical Journal.

    See the full article here .


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    Major Instrumentation

    Wide Field Camera 3 [WFC3]

    NASA/ESA Hubble WFC3.

    Advanced Camera for Surveys [ACS]

    NASA Hubble Advanced Camera for Surveys.

    Cosmic Origins Spectrograph [COS]

    NASA Hubble Cosmic Origins Spectrograph.

    The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

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  • richardmitnick 11:39 am on October 6, 2020 Permalink | Reply
    Tags: "2020 Nobel Prize in Physics awarded for research with ESO telescopes on Milky Way's supermassive black hole", , , , , ESO - European Southern Observatory, Reinhard Genzel of Max Planck Institute for Extraterrestrial Physics and University of California Berkeley.,   

    From European Southern Observatory: “2020 Nobel Prize in Physics awarded for research with ESO telescopes on Milky Way’s supermassive black hole” 

    ESO 50 Large

    From European Southern Observatory

    6 October 2020

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Email: pio@eso.org

    Reinhard Genzel and Andrea Ghez have jointly been awarded the 2020 Nobel Prize in Physics for their work on the supermassive black hole, Sagittarius A*, at the centre of our galaxy. Genzel, Director at the Max Planck Institute for Extraterrestrial Physics in Germany, and his team have conducted observations of Sagittarius A* for nearly 30 years using a fleet of instruments on European Southern Observatory (ESO) telescopes.

    Sgr A* from ESO VLT.

    Genzel shares half of the prize with Ghez, a professor at the University of California, Los Angeles in the US, “for the discovery of a supermassive compact object at the centre of our galaxy”, with the other half awarded to Roger Penrose, professor at the University of Oxford in the UK, “for the discovery that black hole formation is a robust prediction of the general theory of relativity.”

    2
    Roger Penrose, Emeritus Rouse Ball Professor of Mathematics at the University of Oxford.
    Andrea Ghez, UCLA Galactic Center Group.
    Reinhard Genzel, Max Planck Institute for Extraterrestrial Physics, University of California, Berkeley.

    “Congratulations to all three Nobel laureates! We are delighted that the research on the supermassive black hole at the centre of our galaxy has been recognised with the 2020 Nobel Prize in Physics. We are proud that the telescopes ESO builds and operates at its observatories in Chile played a key role in this discovery,” says ESO’s Director General Xavier Barcons. “The work done by Reinhard Genzel with ESO telescopes and by Andrea Ghez with the Keck telescopes in Hawaii has enabled unprecedented insight into Sagittarius A*, which confirmed predictions of Einstein’s general relativity.”

    ESO has worked in very close collaboration with Genzel and his group for around 30 years. Since the early 1990s, Genzel and his team, in cooperation with ESO, have developed instruments designed to track the orbits of stars in the Sagittarius A* region at the centre of the Milky Way.

    They started their campaign in 1992 using the SHARP instrument [N/A] on ESO’s New Technology Telescope (NTT) [below] at the La Silla Observatory in Chile. The team later used extremely sensitive instruments on ESO’s Very Large Telescope (VLT) and the Very Large Telescope Interferometer at the Paranal Observatory, namely NACO, SINFONI and later GRAVITY, to continue their study of Sagittarius A*.

    ESO/NACO on Unit Telescope 1 (UT1).

    ESO/SINFONI installed at the Cassegrain focus of UT3 on the VLT.

    ESO GRAVITY in the VLTI

    In 2008, after 16 years of tracking stars orbiting Sagittarius A*, the team delivered the best empirical evidence that a supermassive black hole exists at the centre of our galaxy. Both Genzel’s and Ghez’s groups accurately traced the orbit of one star in particular, S2, which reached the closest distance to Sagittarius A* in May 2018.

    Star S0-2 Andrea Ghez Keck/UCLA Galactic Center Group at SGR A*, the supermassive black hole at the center of the Milky Way.

    ESO undertook a number of developments and infrastructure upgrades in Paranal to enable accurate measurements of the position and velocity of S2. The team led by Genzel found the light emitted by the star close to the supermassive black hole was stretched to longer wavelengths, an effect known as gravitational redshift, confirming for the first time Einstein’s general relativity near a supermassive black hole. Earlier this year, the team announced they had seen S2 ‘dance’ around the supermassive black hole, showing its orbit is shaped like a rosette, an effect called Schwarzschild precession that was predicted by Einstein.

    Genzel and his team are also involved in the development of instruments that will be installed on ESO’s Extremely Large Telescope, currently under construction in Chile’s Atacama Desert, which will enable them to probe the environment even closer to the supermassive black hole.

    See the full article here .


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    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres.

    ESO VLT at Cerro Paranal in the Atacama Desert.

    ESO VLT 4 lasers on Yepun.

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    ESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

     
  • richardmitnick 7:42 am on October 1, 2020 Permalink | Reply
    Tags: "ESO telescope spots galaxies trapped in the web of a supermassive black hole", , , , , ESO - European Southern Observatory,   

    From European Southern Observatory: “ESO telescope spots galaxies trapped in the web of a supermassive black hole” 

    ESO 50 Large

    From European Southern Observatory

    1 October 2020

    Marco Mignoli
    INAF Bologna
    Bologna, Italy
    Tel: +39 051 6357 382
    Email: marco.mignoli@inaf.it

    Roberto Gilli
    INAF Bologna
    Bologna, Italy
    Tel: +39 051 6357 383
    Email: roberto.gilli@inaf.it

    Barbara Balmaverde
    INAF Torino
    Pino Torinese, Italy
    Email: barbara.balmaverde@inaf.it

    Colin Norman
    Johns Hopkins University
    Baltimore, USA
    Email: norman@stsci.edu

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    With the help of ESO’s Very Large Telescope (VLT) [below] , astronomers have found six galaxies lying around a supermassive black hole when the Universe was less than a billion years old. This is the first time such a close grouping has been seen so soon after the Big Bang and the finding helps us better understand how supermassive black holes, one of which exists at the centre of our Milky Way, formed and grew to their enormous sizes so quickly.

    Sgr A* from ESO VLT.


    SGR A and SGR A* from Penn State and NASA/Chandra.

    It supports the theory that black holes can grow rapidly within large, web-like structures which contain plenty of gas to fuel them.

    “This research was mainly driven by the desire to understand some of the most challenging astronomical objects — supermassive black holes in the early Universe. These are extreme systems and to date we have had no good explanation for their existence,” said Marco Mignoli, an astronomer at the National Institute for Astrophysics (INAF) in Bologna, Italy, and lead author of the new research published today in Astronomy & Astrophysics.

    The new observations with ESO’s VLT revealed several galaxies surrounding a supermassive black hole, all lying in a cosmic “spider’s web” of gas extending to over 300 times the size of the Milky Way. “The cosmic web filaments are like spider’s web threads,” explains Mignoli. “The galaxies stand and grow where the filaments cross, and streams of gas — available to fuel both the galaxies and the central supermassive black hole — can flow along the filaments.”

    The light from this large web-like structure, with its black hole of one billion solar masses, has travelled to us from a time when the Universe was only 0.9 billion years old. “Our work has placed an important piece in the largely incomplete puzzle that is the formation and growth of such extreme, yet relatively abundant, objects so quickly after the Big Bang,” says co-author Roberto Gilli, also an astronomer at INAF in Bologna, referring to supermassive black holes.

    The very first black holes, thought to have formed from the collapse of the first stars, must have grown very fast to reach masses of a billion suns within the first 0.9 billion years of the Universe’s life. But astronomers have struggled to explain how sufficiently large amounts of “black hole fuel” could have been available to enable these objects to grow to such enormous sizes in such a short time. The new-found structure offers a likely explanation: the “spider’s web” and the galaxies within it contain enough gas to provide the fuel that the central black hole needs to quickly become a supermassive giant.

    But how did such large web-like structures form in the first place? Astronomers think giant halos of mysterious dark matter are key. These large regions of invisible matter are thought to attract huge amounts of gas in the early Universe; together, the gas and the invisible dark matter form the web-like structures where galaxies and black holes can evolve.

    “Our finding lends support to the idea that the most distant and massive black holes form and grow within massive dark matter halos in large-scale structures, and that the absence of earlier detections of such structures was likely due to observational limitations,” says Colin Norman of Johns Hopkins University in Baltimore, US, also a co-author on the study.

    The galaxies now detected are some of the faintest that current telescopes can observe. This discovery required observations over several hours using the largest optical telescopes available, including ESO’s VLT. Using the MUSE and FORS2 instruments on the VLT at ESO’s Paranal Observatory in the Chilean Atacama Desert, the team confirmed the link between four of the six galaxies and the black hole.

    ESO MUSE on the VLT on Yepun (UT4).

    ESO FORS2 VLT mounted on Unit Telescope 1 (Antu).

    “We believe we have just seen the tip of the iceberg, and that the few galaxies discovered so far around this supermassive black hole are only the brightest ones,” said co-author Barbara Balmaverde, an astronomer at INAF in Torino, Italy.

    These results contribute to our understanding of how supermassive black holes and large cosmic structures formed and evolved. ESO’s Extremely Large Telescope, currently under construction in Chile, will be able to build on this research by observing many more fainter galaxies around massive black holes in the early Universe using its powerful instruments.

    More information

    The team is composed of M. Mignoli (INAF, Bologna, Italy), R. Gilli (INAF, Bologna, Italy), R. Decarli (INAF, Bologna, Italy), E. Vanzella (INAF, Bologna, Italy), B. Balmaverde (INAF, Pino Torinese, Italy), N. Cappelluti (Department of Physics, University of Miami, Florida, USA), L. Cassarà (INAF, Milano, Italy), A. Comastri (INAF, Bologna, Italy), F. Cusano (INAF, Bologna, Italy), K. Iwasawa (ICCUB, Universitat de Barcelona & ICREA, Barcelona, Spain), S. Marchesi (INAF, Bologna, Italy), I. Prandoni (INAF, Istituto di Radioastronomia, Bologna, Italy), C. Vignali (Dipartimento di Fisica e Astronomia, Università degli Studi di Bologna, Italy & INAF, Bologna, Italy), F. Vito (Scuola Normale Superiore, Pisa, Italy), G. Zamorani (INAF, Bologna, Italy), M. Chiaberge (Space Telescope Science Institute, Maryland, USA), C. Norman (Space Telescope Science Institute & Johns Hopkins University, Maryland, USA).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Visit ESO in Social Media-

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    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres.

    ESO VLT at Cerro Paranal in the Atacama Desert.

    ESO VLT 4 lasers on Yepun.

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    ESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

     
  • richardmitnick 1:54 pm on September 3, 2020 Permalink | Reply
    Tags: "New Observations Show Planet-forming Disc Torn Apart by its Three Central Stars", , , , , ESO - European Southern Observatory   

    From European Southern Observatory: “New Observations Show Planet-forming Disc Torn Apart by its Three Central Stars” 

    ESO 50 Large

    From European Southern Observatory

    3 September 2020
    Stefan Kraus
    Associate Professor in Astrophysics, University of Exeter
    Exeter, UK
    Tel: +44 1392 724125
    Email: S.Kraus@exeter.ac.uk

    Alexander Kreplin
    Postdoctoral Research Fellow, University of Exeter
    Exeter, UK
    Tel: +44 1392 725571
    Email: A.Kreplin@exeter.ac.uk

    Alison Young
    Postdoctoral Research Associate, University of Leicester
    Leicester, UK
    Tel: +44 116 3736281
    Email: alison.young@leicester.ac.uk

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    A team of astronomers have identified the first direct evidence that groups of stars can tear apart their planet-forming disc, leaving it warped and with tilted rings. This new research suggests exotic planets, not unlike Tatooine in Star Wars, may form in inclined rings in bent discs around multiple stars. The results were made possible thanks to observations with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) [below] and the Atacama Large Millimeter/submillimeter Array (ALMA) [below].

    2
    ALMA, in which ESO is a partner, and the SPHERE instrument on ESO’s Very Large Telescope have imaged GW Orionis, a triple star system with a peculiar inner region. Unlike the flat planet-forming discs we see around many stars, GW Orionis features a warped disc, deformed by the movements of the three stars at its centre. The ALMA image (left) shows the disc’s ringed structure, with the innermost ring separated from the rest of the disc. The SPHERE observations (right) allowed astronomers to see for the first time the shadow of this innermost ring on the rest of the disc, which made it possible for them to reconstruct its warped shape. Credit: ALMA (ESO/NAOJ/NRAO), ESO/Exeter/Kraus et al.

    3
    ALMA, in which ESO is a partner, and the SPHERE instrument on ESO’s Very Large Telescope have imaged GW Orionis, a triple star system with a peculiar inner region. Unlike the flat planet-forming discs we see around many stars, GW Orionis features a warped disc, deformed by the movements of the three stars at its centre. This composite image shows both the ALMA and SPHERE observations of the disc. The ALMA image shows the disc’s ringed structure, with the innermost ring (part of which is visible as an oblong dot at the very centre of the image) separated from the rest of the disc. The SPHERE observations allowed astronomers to see for the first time the shadow of this innermost ring on the rest of the disc, which made it possible for them to reconstruct its warped shape. Credit: ESO/Exeter/Kraus et al., ALMA (ESO/NAOJ/NRAO).

    Our Solar System is remarkably flat, with the planets all orbiting in the same plane. But this is not always the case, especially for planet-forming discs around multiple stars, like the object of the new study: GW Orionis. This system, located just over 1300 light-years away in the constellation of Orion, has three stars and a deformed, broken-apart disc surrounding them.

    “Our images reveal an extreme case where the disc is not flat at all, but is warped and has a misaligned ring that has broken away from the disc,” says Stefan Kraus, a professor of astrophysics at the University of Exeter in the UK who led the research published today in the journal Science. The misaligned ring is located in the inner part of the disc, close to the three stars.

    The new research also reveals that this inner ring contains 30 Earth-masses of dust, which could be enough to form planets. “Any planets formed within the misaligned ring will orbit the star on highly oblique orbits and we predict that many planets on oblique, wide-separation orbits will be discovered in future planet imaging campaigns, for instance with the ELT,” says team member Alexander Kreplin of the University of Exeter, referring to ESO’s Extremely Large Telescope, which is planned to start operating later this decade. Since more than half the stars in the sky are born with one or more companions, this raises an exciting prospect: there could be an unknown population of exoplanets that orbit their stars on very inclined and distant orbits.

    To reach these conclusions, the team observed GW Orionis for over 11 years. Starting in 2008, they used the AMBER and later the GRAVITY instruments on ESO’s VLT Interferometer in Chile, which combines the light from different VLT telescopes, to study the gravitational dance of the three stars in the system and map their orbits.

    ESO VLTI -AMBER

    ESO GRAVITY in the VLTI

    “We found that the three stars do not orbit in the same plane, but their orbits are misaligned with respect to each other and with respect to the disc,” says Alison Young of the Universities of Exeter and Leicester and a member of the team.

    They also observed the system with the SPHERE instrument on ESO’s VLT and with ALMA, in which ESO is a partner, and were able to image the inner ring and confirm its misalignment.

    ESO SPHERE extreme adaptive optics system and coronagraphic facility on the extreme adaptive optics system and coronagraphic facility on the VLT MELIPAL UT3, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level

    ESO’s SPHERE also allowed them to see, for the first time, the shadow that this ring casts on the rest of the disc. This helped them figure out the 3D shape of the ring and the overall disc.

    The international team, which includes researchers from the UK, Belgium, Chile, France and the US, then combined their exhaustive observations with computer simulations [for the most computation-extensive simulations the Exeter supercomputer ISCA

    4

    was used] to understand what had happened to the system. For the first time, they were able to clearly link the observed misalignments to the theoretical “disc-tearing effect”, which suggests that the conflicting gravitational pull of stars in different planes can warp and break their discs.

    Their simulations showed that the misalignment in the orbits of the three stars could cause the disc around them to break into distinct rings, which is exactly what they see in their observations. The observed shape of the inner ring also matches predictions from numerical simulations on how the disc would tear.

    Interestingly, another team who studied the same system using ALMA believe another ingredient is needed to understand the system. “We think that the presence of a planet between these rings is needed to explain why the disc tore apart,” says Jiaqing Bi of the University of Victoria in Canada who led a study of GW Orionis published in The Astrophysical Journal Letters in May this year. His team identified three dust rings in the ALMA observations, with the outermost ring being the largest ever observed in planet-forming discs.

    Future observations with ESO’s ELT [below] and other telescopes may help astronomers fully unravel the nature of GW Orionis and reveal young planets forming around its three stars.

    More information

    This research was presented in the paper “A triple star system with a misaligned and warped circumstellar disk shaped by disk tearing” to appear in Science.

    The team is composed of Stefan Kraus (University of Exeter, School of Physics & Astronomy, UK [Exeter]) Alexander Kreplin (Exeter), Alison K. Young (Exeter and School of Physics and Astronomy, University of Leicester, UK), Matthew R. Bate (Exeter), John D. Monnier (University of Michigan, USA [Michigan]), Tim J. Harries (Exeter), Henning Avenhaus (Max Planck Institute for Astronomy, Heidelberg, Germany), Jacques Kluska (Exeter and Instituut voor Sterrenkunde, KU Leuven, Belgium [KU Leuven]), Anna S. E. Laws (Exeter), Evan A. Rich (Michigan), Matthew Willson (Exeter and Georgia State University, USA), Alicia N. Aarnio (University of North Carolina Greensboro, USA), Fred C. Adams (Michigan), Sean M. Andrews (Center for Astrophysics | Harvard & Smithsonian, USA [CfA]), Narsireddy Anugu (Exeter, Michigan and Steward Observatory, University of Arizona, USA), Jaehan Bae (Michigan and Carnegie Institution for Science, Washington, USA), Theo ten Brummelaar (The CHARA Array of Georgia State University, California, USA), Nuria Calvet (Michigan), Michel Cure (Instituto de Fisica y Astronomia, Universidad de Valparaiso, Chile), Claire L. Davies (Exeter), Jacob Ennis (Michigan), Catherine Espaillat (Michigan and Boston University, USA), Tyler Gardner (Michigan), Lee Hartmann (Michigan), Sasha Hinkley (Exeter), Aaron Labdon (Exeter), Cyprien Lanthermann (KU Leuven), Jean-Baptiste LeBouquin (Michigan and Universite Grenoble Alpes, CNRS, IPAG, France), Gail H. Schaefer (CHARA), Benjamin R. Setterholm (Michigan), David Wilner (CfA), and Zhaohuan Zhu (University of Nevada, USA).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Visit ESO in Social Media-

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    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres


    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov
    Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 9:42 am on July 30, 2020 Permalink | Reply
    Tags: "Stunning Space Butterfly Captured by ESO Telescope", , , , , ESO - European Southern Observatory, The fantastic NGC 2899 planetary nebula   

    From European Southern Observatory: “Stunning Space Butterfly Captured by ESO Telescope” 

    ESO 50 Large

    From European Southern Observatory

    30 July 2020
    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    This highly detailed image of the fantastic NGC 2899 planetary nebula was captured using the FORS instrument on ESO’s Very Large Telescope in northern Chile. This object has never before been imaged in such striking detail, with even the faint outer edges of the planetary nebula glowing over the background stars. Credit:ESO.

    Resembling a butterfly with its symmetrical structure, beautiful colours, and intricate patterns, this striking bubble of gas — known as NGC 2899 — appears to float and flutter across the sky in this new picture from ESO’s Very Large Telescope (VLT) [below]. This object has never before been imaged in such striking detail, with even the faint outer edges of the planetary nebula glowing over the background stars.

    NGC 2899’s vast swathes of gas extend up to a maximum of two light-years from its centre, glowing brightly in front of the stars of the Milky Way as the gas reaches temperatures upwards of ten thousand degrees. The high temperatures are due to the large amount of radiation from the nebula’s parent star, which causes the hydrogen gas in the nebula to glow in a reddish halo around the oxygen gas, in blue.

    This object, located between 3000 and 6500 light-years away in the Southern constellation of Vela (The Sails), has two central stars, which are believed to give it its nearly symmetric appearance. After one star reached the end of its life and cast off its outer layers, the other star now interferes with the flow of gas, forming the two-lobed shape seen here. Only about 10–20% of planetary nebulae [1] display this type of bipolar shape.

    Astronomers were able to capture this highly detailed image of NGC 2899 using the FORS instrument installed on UT1 (Antu), one of the four 8.2-metre telescopes that make up ESO’s VLT in Chile.

    ESO FORS2 VLT mounted on Unit Telescope 1 (Antu)

    Standing for FOcal Reducer and low dispersion Spectrograph, this high-resolution instrument was one of the first to be installed on ESO’s VLT and is behind numerous beautiful images and discoveries from ESO. FORS has contributed to observations of light from a gravitational wave source, has researched the first known interstellar asteroid, and has been used to study in depth the physics behind the formation of complex planetary nebulae.

    This image was created under the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.

    Notes

    [1] Unlike what their common name suggests, planetary nebulae have nothing to do with planets. The first astronomers to observe them merely described them as planet-like in appearance. They are instead formed when ancient stars with up to 6 times the mass of our Sun reach the end of their lives, collapse, and blow off expanding shells of gas, rich in heavy elements. Intense ultraviolet radiation energises and lights up these moving shells, causing them to shine brightly for thousands of years until they ultimately disperse slowly through space, making planetary nebulae relatively short-lived phenomena on astronomical timescales.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres


    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov
    Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 5:05 pm on July 26, 2020 Permalink | Reply
    Tags: "How old are the stars?", Accurately measuring the ages of the stars is the missing piece in the puzzle of Galactic archaeology that would help us understand how the Milky Way formed and evolved., , , , Chemical clocks, , , ESO - European Southern Observatory, , Giada Casali, HARPS instrument on the ESO 3.6-metre telescope, Isochrone fitting method, , Laura Magrini, , The Gaia-ESO survey is the largest public spectroscopic survey (it used the Very Large Telescope (VLT) for over 300 nights!) carried out on an eight-metre-diameter telescope.   

    From ESOblog: “How old are the stars?” 

    ESO 50 Large

    From ESOblog

    24 July 2020

    1
    Science Snapshots

    2
    Giada Casali and Laura Magrini

    It’s one of the biggest challenges in astrophysics: accurately measuring the ages of the stars is the missing piece in the puzzle of Galactic archaeology that would help us understand how the Milky Way formed and evolved. Scientists have started using the novel “chemical clocks” method to measure the ages of stars close to the Sun, but a team of astronomers recently used data from ESO telescopes to discover that the situation becomes much more complicated when we move outside our solar neighbourhood. We find out more from the scientists who led the research.

    Q. Firstly, what exactly do you mean when you talk about “chemical clocks”?

    Giada Casali (GC): When we talk about chemical clocks, we are referring to the ratios between particular pairs of elements — called chemical abundance ratios — in a star, that display a strong dependence on age. Every star is made up of lots of different elements that are produced in different processes and at different time scales, which is why we can use them as an innovative way to measure a star’s age.

    Laura Magrini (LM): For example, massive stars produce some elements quickly, whereas smaller stars produce them more slowly. So in theory, by looking at the spectrum of light from a star and measuring the abundance ratio between an element produced very quickly (when the Galaxy was very young) and an element produced much more slowly (and therefore only produced recently), we have a sort of track of when a star formed, and can therefore predict its age. Using stars located very close to the Sun, astronomers have discovered relations between age and some specific age-dependent abundance ratios. But we wanted to know: Are these relations universal? Can they be applied to all the stars in our Galaxy?

    2
    In April 2015 the HARPS laser frequency comb was installed on the HARPS planet-finding instrument on the ESO 3.6-metre telescope at the La Silla Observatory in Chile after completion of an intense first commissioning phase. The increase in accuracy made possible by this new installation should in future allow HARPS to be able to detect Earth-mass planets in Earth-like orbits around other stars for the first time. Credit ESO.

    ESO/HARPS at La Silla


    ESO 3.6m telescope & HARPS at Cerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    This picture shows a HARPS spectrum of the light from the two laser frequency combs that that were tested. Credit: ESO.

    Q. Could you summarise what you found in this research [Astronomy and Astrophysics] ?

    LM: Our idea, matured with Lorenzo Spina at Monash University in Australia, was to use archival data from the HARPS instrument on the ESO 3.6-metre telescope to measure specific chemical clocks in stars similar to the Sun, but with different abundances of elements heavier than helium and hydrogen. When we say “similar to the Sun”, we mean stars with very similar surface temperature and surface gravity and we call them solar-like stars; selecting such stars means that any variation in their spectrum of light is due to differences in chemical abundances, which we can presume are related only to their age.

    GC: We compared the ages of the solar-like stars, calculated due to their very well-known properties, with the ratios of specific elements, for example yttrium to magnesium, which is particularly strongly dependent on age. We were expecting to be able to apply our relation everywhere, but when we looked at the yttrium to magnesium ratio in stars further away from the Sun, in the direction of the Galactic centre, we found less yttrium than we would expect to find in stars of the same age close to the Sun. This means that this specific chemical clock relationship doesn’t apply in the same way everywhere in the Milky Way!

    Q. Were you surprised by this discovery?

    LM: Absolutely! Previous studies gave us hope that there may be a universal relationship between chemical clocks and age for solar-like stars throughout the Milky Way, but we found that this relationship can’t be applied everywhere. We think the difference arises because the stars didn’t all form at the same time, rather the Galaxy formed “inside out”, with the inner parts forming the quickest. This means that the star formation process varies throughout the Galaxy and the contribution of low and high mass stars with varying amounts of heavy elements is different in different places and at different epochs.

    4
    A Hertzsprung-Russell diagram for open clusters observed with the European Space Agency’s Gaia mission, plotted over an image of open cluster NGC 3293. Credit: Gaia data – ESA/Gaia/DPAC, Carine Babusiaux and co-authors of the paper Gaia Data Release 2: Observational Hertzsprung-Russell diagrams; Credit NGC 3293 – ESO/G. Beccari; Credit graphic design – R. Spiga (INAF)

    ESA/GAIA satellite

    The x axis shows the colour of stars in open clusters, and the y axis shows their apparent brightness as seen from Earth.

    Q. So why did you decide to carry out this research in the first place?

    GC: We wanted to investigate another method to date stars. Determining stellar ages is really important for astronomers to understand how the Milky Way formed and evolved, but it’s actually one of the most difficult parts of astrophysics. The most common technique used at the moment is called isochrone fitting; this technique compares the observed colours and brightnesses of stars with the expected ones from theoretical predictions, and from that comparison it infers the ages of the stars.

    The technique works very well for groups of stars all of the same age, for example members of star clusters. However, it is very difficult to use it to date individual stars, unless their properties are particularly well known. For solar-like stars, we do know their properties, so we can calibrate the new chemical clock method with the isochrone fitting method to find a new way to date stars with unknown properties.

    LM: Our idea was to find a universal relation, valid across the entire Milky Way, that would allow us to measure stellar ages simply by measuring their chemical composition…but life is always more complicated! In the past, we looked specifically at the abundance between carbon and nitrogen, which is a very effective method of figuring out the ages of giant stars. We found that since this abundance ratio essentially depends on stellar evolution, it is effectively valid across the entire Galactic disc, while it can vary, for instance, in the Galactic halo.

    Caterpillar Project A Milky-Way-size dark-matter halo and its subhalos circled, an enormous suite of simulations . Griffen et al. 2016

    Our ultimate aim is to collect different chemical relations for many stars that we know the ages of. The Gaia-ESO survey — which we used for both pieces of research — is the largest public spectroscopic survey (it used the Very Large Telescope (VLT) for over 300 nights!) carried out on an eight-metre-diameter telescope. It provides the most accurate database of detailed chemical abundances in stars across all the components of the Galaxy, and is also the only one focusing on star clusters, sampling all stars from young to old. The Gaia-ESO survey, therefore, is a fundamental tool for our research.

    Q. What are the implications of this discovery?

    LM: The result means that astronomers need to be more careful when they are trying to work out the ages of stars, as it is not as simple as we had previously assumed. We applied the relationships we found for different pairs of chemical elements in the HARPS data for nearby stars to open star clusters observed in the Gaia-ESO survey, and found that our relationship, built for the solar neighbourhood, does not correctly calculate the ages of stars in clusters in the Milky Way’s inner disc, where star formation and evolution happens much faster.

    We know that the Milky Way is made up of two discs of stars — one thin and one thick. Recent results from the European Space Agency’s Gaia satellite show that the thick disc probably formed through the interaction of the Milky Way with another galaxy several billion years ago, and that the stars in each disc have different ages. It is known that the stars in the thick disc contain much more magnesium than iron, for example, suggesting a different star formation history. Using our chemical clock relations, we were able to confirm the difference in ages of the two discs for stars located close to the Sun.

    5
    The anatomy of the Milky Way.
    Left: NASA/JPL Caltech, R Hurt; Right: ESA, Layout: ESA/ATG Medialab

    Q. Why do you think is it important to measure the ages of stars and understand the formation and the evolution of the Milky Way?

    LM: The only place that we can measure the ages of individual stars so precisely is the Milky Way. So by investigating these stars in more detail, we can better understand spiral galaxies, which are among the most common — and for me the most beautiful — type of galaxies in the Universe. As the luminous part of the Universe, galaxies are our “window” to understanding the Universe’s evolution; they are vital for understanding how it formed and evolved, and what its future could hold.

    Q. Do you plan to follow up this research in any way?

    GC: We want to dig deeper into the relationship between various chemical abundance ratios and distance from the centre of the Milky Way using open star clusters as a calibrator. In particular we will continue to use data from the Gaia-ESO survey and APOGEE.

    LM: In just a few years, the Extremely Large Telescope (ELT) will be up and running, and will allow us to resolve stars — and obtain their individual light spectra — in other galaxies with a similar detail to what we can now achieve only in the Milky Way. The ELT will be able to look at individual stars in other galaxies in our Local Group, and in the Virgo cluster of galaxies, so that we can measure their chemical composition and extend our studies to different environments.

    6
    Seen from the southern skies, the Large and Small Magellanic Clouds (the LMC and SMC, respectively) are bright patches in the sky. These two irregular dwarf galaxies, together with our Milky Way Galaxy, belong to the so-called Local Group of galaxies.

    Local Group. Andrew Z. Colvin 3 March 2011

    Astronomers once thought that the two Magellanic Clouds orbited the Milky Way, but recent research suggests this is not the case, and that they are in fact on their first pass by the Milky Way.

    The LMC, lying at a distance of 160 000 light-years, and its neighbour the SMC, some 200,000 light-years away, are among the largest distant objects we can observe with the unaided eye. Both galaxies have notable bar features across their central discs, although the very strong tidal forces exerted by the Milky Way have distorted the galaxies considerably. The mutual gravitational pull of the three interacting galaxies has drawn out long streams of neutral hydrogen that interlink the three galaxies.

    Magellanic Bridge ESA Gaia satellite. Image credit V. Belokurov D. Erkal A. Mellinger.

    On 23 February 1987 the LMC hosted a dramatic cosmic explosion when a supernova (SN 1987A) ignited near the Tarantula Nebula. SN 1987A ranks among the brightest and closest events of this kind ever observed in recorded history.

    SN 1987A remnant, imaged by ALMA. The inner region is contrasted with the outer shell, lacy white and blue circles, where the blast wave from the supernova is colliding with the envelope of gas ejected from the star prior to its powerful detonation. Image credit: ALMA / ESO / NAOJ / NRAO / Alexandra Angelich, NRAO / AUI / NSF.

    Al Sufi, the Persian astronomer, described the LMC for the first time in his Book of Fixed Stars in AD 964. He called it Al Bakr, describing it as the White Ox of southern Arabia. Referred to in some older books as Nubecula Major and Minor, the Clouds take their modern name from the explorer Ferdinand Magellan, who first recorded their existence on his voyage of circumnavigation in 1519–22, and brought news of them to Europe; although a letter written by Amerigo Vespucci during his third voyage about 1503–4 may refer to them indirectly. Credit: ESO/S. Brunier

    Biography Giada Casali and Laura Magrini

    Giada Casali is a PhD student in her final year at the University of Florence/INAF-Astrophysical Observatory of Arcetri (Italy). She obtained her bachelor’s and master’s degrees at the University of Pisa (Italy). Giada has been working in the field of galactic archaeology, combining data collected by the European Space Agency’s Gaia satellite and ground-based large spectroscopic surveys. Her expertise mainly focuses on stellar spectroscopy and the determination of stellar ages.

    Laura Magrini obtained her PhD in 2003 at the University of Florence (Italy), in collaboration with the Instituto de Astronomía de Canarias (Spain). After several postdoctoral positions in the field of galactic archaeology, since 2012 she has worked as a researcher at the INAF-Astrophysical Observatory of Arcetri. She works on galaxy formation and evolution, using spectroscopic data of stellar populations in the Milky Way and nearby galaxies.

    See the full article here .


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    Please help promote STEM in your local schools.

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    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo,

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system


    ESO LaSilla
    ESO/Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT 4 lasers on Yepun


    ESO Vista Telescope
    ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO NTT
    ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT Survey telescope
    VLT Survey Telescope at Cerro Paranal with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Cherenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 8:18 am on July 22, 2020 Permalink | Reply
    Tags: "First Ever Image of a Multi-Planet System around a Sun-like Star Captured by ESO Telescope", A star like our Sun located about 300 light-years away and known as TYC 8998-760-1., An environment that is very similar to our Solar System; but at a much earlier stage of its evolution., , , , , ESO - European Southern Observatory   

    From European Southern Observatory: “First Ever Image of a Multi-Planet System around a Sun-like Star Captured by ESO Telescope” Image Release 

    ESO 50 Large

    From European Southern Observatory

    22 July 2020

    Contacts

    Alexander Bohn
    Leiden Observatory, University of Leiden
    Leiden, The Netherlands
    Tel: +31 (0)71 527 8150
    Email: bohn@strw.leidenuniv.nl

    Matthew Kenworthy
    Leiden Observatory, University of Leiden
    Leiden, The Netherlands
    Tel: +31 64 172 0331
    Email: kenworthy@strw.leidenuniv.nl

    Maddalena Reggiani
    Institute of Astronomy, KU Leuven
    Leuven, Belgium
    Tel: +32 16 19 31 99
    Email: maddalena.reggiani@kuleuven.be

    Carlo Manara (astronomer who did not participate in the study; contact for external comment)
    European Southern Observatory
    Garching bei München, Germany
    Tel: +49 (0) 89 3200 6298
    Email: cmanara@eso.org

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    First ever image of a multi-planet system around a Sun-like star (uncropped, with annotations).
    This image, captured by the SPHERE [below] instrument on ESO’s Very Large Telescope [below], shows the star TYC 8998-760-1 accompanied by two giant exoplanets, TYC 8998-760-1b and TYC 8998-760-1c. This is the first time astronomers have directly observed more than one planet orbiting a star similar to the Sun.

    The two planets are visible as two bright dots in the centre (TYC 8998-760-1b) and bottom right (TYC 8998-760-1c) of the frame, noted by arrows. Other bright dots, which are background stars, are visible in the image as well. By taking different images at different times, the team were able to distinguish the planets from the background stars.

    The image was captured by blocking the light from the young, Sun-like star (top-left of centre) using a coronagraph, which allows for the fainter planets to be detected. The bright and dark rings we see on the star’s image are optical artefacts. Credit: ESO/Bohn et al.

    ESO SPHERE extreme adaptive optics system and coronagraphic facility on the extreme adaptive optics system and coronagraphic facility on the VLT UT3, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level

    This is the first time astronomers have directly observed more than one planet orbiting a star similar to the Sun. The image was captured by blocking the light from the young, Sun-like star (on the top left corner) using a coronagraph, which allows for the fainter planets to be detected. The bright and dark rings we see on the star’s image are optical artefacts. The two planets are visible as two bright dots in the centre and bottom right of the frame. Credit: ESO/Bohn et al.

    __________________________________________

    Just a few weeks ago, ESO revealed a planetary system being born in a new, stunning VLT image. Now, the same telescope, using the same instrument, has taken the first direct image of a planetary system around a star like our Sun, located about 300 light-years away and known as TYC 8998-760-1.

    Example of direct imaging-This false-color composite image traces the motion of the planet Fomalhaut b, a world captured by direct imaging. Credit: NASA, ESA, and P. Kalas (University of California, Berkeley and SETI Institute)

    “This discovery is a snapshot of an environment that is very similar to our Solar System, but at a much earlier stage of its evolution,” says Alexander Bohn, a PhD student at Leiden University in the Netherlands, who led the new research published today in The Astrophysical Journal Letters.

    “Even though astronomers have indirectly detected thousands of planets in our galaxy, only a tiny fraction of these exoplanets have been directly imaged,” says co-author Matthew Kenworthy, Associate Professor at Leiden University, adding that “direct observations are important in the search for environments that can support life.” The direct imaging of two or more exoplanets around the same star is even more rare; only two such systems have been directly observed so far, both around stars markedly different from our Sun. The new ESO’s VLT image is the first direct image of more than one exoplanet around a Sun-like star. ESO’s VLT was also the first telescope to directly image an exoplanet, back in 2004, when it captured a speck of light around a brown dwarf, a type of ‘failed’ star.

    “Our team has now been able to take the first image of two gas giant companions that are orbiting a young, solar analogue,” says Maddalena Reggiani, a postdoctoral researcher from KU Leuven, Belgium, who also participated in the study. The two planets can be seen in the new image as two bright points of light distant from their parent star, which is located in the upper left of the frame (click on the image to view the full frame). By taking different images at different times, the team were able to distinguish these planets from the background stars.

    The two gas giants orbit their host star at distances of 160 and about 320 times the Earth-Sun distance. This places these planets much further away from their star than Jupiter or Saturn, also two gas giants, are from the Sun; they lie at only 5 and 10 times the Earth-Sun distance, respectively. The team also found the two exoplanets are much heavier than the ones in our Solar System, the inner planet having 14 times Jupiter’s mass and the outer one six times.

    Bohn’s team imaged this system during their search for young, giant planets around stars like our Sun but far younger. The star TYC 8998-760-1 is just 17 million years old and located in the Southern constellation of Musca (The Fly). Bohn describes it as a “very young version of our own Sun.”

    These images were possible thanks to the high performance of the SPHERE instrument [above] on ESO’s VLT [below] in the Chilean Atacama desert. SPHERE blocks the bright light from the star using a device called coronagraph, allowing the much fainter planets to be seen. While older planets, such as those in our Solar System, are too cool to be found with this technique, young planets are hotter, and so glow brighter in infrared light. By taking several images over the past year, as well as using older data going back to 2017, the research team have confirmed that the two planets are part of the star’s system.

    Further observations of this system, including with the future ESO Extremely Large Telescope (ELT) [below], will enable astronomers to test whether these planets formed at their current location distant from the star or migrated from elsewhere. ESO’s ELT will also help probe the interaction between two young planets in the same system. Bohn concludes: “The possibility that future instruments, such as those available on the ELT, will be able to detect even lower-mass planets around this star marks an important milestone in understanding multi-planet systems, with potential implications for the history of our own Solar System.”

    More Information

    The team is composed of Alexander J. Bohn (Leiden Observatory, Leiden University, The Netherlands), Matthew A. Kenworthy (Leiden Observatory), Christian Ginski (Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands and Leiden Observatory), Steven Rieder (University of Exeter, Physics Department, UK), Eric E. Mamajek (Jet Propulsion Laboratory, California Institute of Technology, USA and Department of Physics & Astronomy, University of Rochester, USA), Tiffany Meshkat (IPAC, California Institute of Technology, USA), Mark J. Pecaut (Rockhurst University, Department of Physics, USA), Maddalena Reggiani (Institute of Astronomy, KU Leuven, Belgium), Jozua de Boer (Leiden Observatory), Christoph U. Keller (Leiden Observatory), Frans Snik (Leiden Observatory) and John Southworth (Keele University, UK).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Visit ESO in Social Media-

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    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Cherenkov Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 7:30 am on June 30, 2020 Permalink | Reply
    Tags: "A Cosmic Mystery: ESO Telescope Captures the Disappearance of a Massive Star", , , , , Disappearence of luminous blue variable star in the Kinman Dwarf galaxy., ESO - European Southern Observatory   

    From European Southern Observatory: “A Cosmic Mystery: ESO Telescope Captures the Disappearance of a Massive Star” 

    ESO 50 Large

    From European Southern Observatory

    30 June 2020

    Andrew Allan
    Trinity College Dublin
    Dublin, Ireland
    Tel: +353 872921396
    Email: allana@tcd.ie

    Jose H. Groh
    Trinity College Dublin
    Dublin, Ireland
    Email: jose.groh@tcd.ie

    Andrea Mehner
    European Southern Observatory
    Santiago, Chile
    Email: amehner@eso.org

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    This illustration shows what the luminous blue variable star in the Kinman Dwarf galaxy could have looked like before its mysterious disappearance. Credit: ESO/L. Calçada

    Using the European Southern Observatory’s Very Large Telescope (VLT) [below], astronomers have discovered the absence of an unstable massive star in a dwarf galaxy. Scientists think this could indicate that the star became less bright and partially obscured by dust. An alternative explanation is that the star collapsed into a black hole without producing a supernova. “If true,” says team leader and PhD student Andrew Allan of Trinity College Dublin, Ireland, “this would be the first direct detection of such a monster star ending its life in this manner.”

    2
    Hubble image of the Kinman Dwarf galaxy.
    Image of the Kinman Dwarf galaxy, also known as PHL 293B, taken with the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 in 2011, before the disappearance of the massive star.

    NASA/ESA Hubble WFC3

    Located some 75 million light-years away, the galaxy is too far away for astronomers to clearly resolve its individual stars, but in observations done between 2001 and 2011, they detected the signatures of the massive star. These signatures were not present in more recent data. Credit: NASA, ESA/Hubble, J. Andrews (U. Arizona)

    4
    This wide-field view shows the region of the sky, in the constellation of Aquarius, where the Kinman Dwarf galaxy can be found. This view was created from images forming part of the Digitized Sky Survey 2. Credit: ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin


    ESOcast 225 Light: ESO Telescope Captures Disappearance of Massive Star
    The video is available in 4K UHD.
    Credit: ESO
    Directed by: Herbert Zodet.
    Editing: Herbert Zodet.
    Web and technical support: Gurvan Bazin and Raquel Yumi Shida.
    Written by: Caitlyn Buongiorno, Stephanie Rowlands and Bárbara Ferreira.
    Music: tonelabs (www.tonelabs.com) – Orion Fog.
    Footage and photos: ESO, L. Calçada, Digitized Sky Survey 2, N. Risinger (skysurvey.org), NASA, ESA/Hubble, J. Andrews (U. Arizona), ACe Consortium and J. Colosimo.
    Scientific consultants: Paola Amico and Mariya Lyubenova.


    This video starts by showing a wide-field view of a region of the sky in the constellation of Aquarius. It then zooms in to show the Kinman Dwarf galaxy, where a mysterious luminous blue variable star disappeared. The end of the video shows an artistic animation of what the star could have looked like before it disappeared. Credit: ESO/L. Calçada, Digitized Sky Survey 2, N. Risinger (skysurvey.org), NASA, ESA/Hubble, J. Andrews (U. Arizona) Music: Konstantino Polizois.

    Between 2001 and 2011, various teams of astronomers studied the mysterious massive star, located in the Kinman Dwarf galaxy, and their observations indicated it was in a late stage of its evolution. Allan and his collaborators in Ireland, Chile and the US wanted to find out more about how very massive stars end their lives, and the object in the Kinman Dwarf seemed like the perfect target. But when they pointed ESO’s VLT to the distant galaxy in 2019, they could no longer find the telltale signatures of the star. “Instead, we were surprised to find out that the star had disappeared!” says Allan, who led a study of the star published today in Monthly Notices of the Royal Astronomical Society.

    Located some 75 million light-years away in the constellation of Aquarius, the Kinman Dwarf galaxy is too far away for astronomers to see its individual stars, but they can detect the signatures of some of them. From 2001 to 2011, the light from the galaxy consistently showed evidence that it hosted a ‘luminous blue variable’ star some 2.5 million times brighter than the Sun. Stars of this type are unstable, showing occasional dramatic shifts in their spectra and brightness. Even with those shifts, luminous blue variables leave specific traces scientists can identify, but they were absent from the data the team collected in 2019, leaving them to wonder what had happened to the star. “It would be highly unusual for such a massive star to disappear without producing a bright supernova explosion,” says Allan.

    The group first turned the ESPRESSO instrument toward the star in August 2019, using the VLT’s four 8-metre telescopes simultaneously.

    ESO/ESPRESSO on the VLT, installed at the incoherent combined Coudé facility of the VLT. It is an ultra-stable fibre-fed échelle high-resolution spectrograph (R~140,000, 190,000, or 70,000) which collects the light from either a single UT or the four UTs simultaneously via the so-called UT Coudé trains.

    But they were unable to find the signs that previously pointed to the presence of the luminous star. A few months later, the group tried the X-shooter instrument, also on ESO’s VLT, and again found no traces of the star.

    ESO X-shooter on VLT on UT2 at Cerro Paranal, Chile

    “We may have detected one of the most massive stars of the local Universe going gently into the night,” says team-member Jose Groh, also of Trinity College Dublin. “Our discovery would not have been made without using the powerful ESO 8-metre telescopes, their unique instrumentation, and the prompt access to those capabilities following the recent agreement of Ireland to join ESO.” Ireland became an ESO member state in September 2018.

    The team then turned to older data collected using X-shooter and the UVES instrument on ESO’s VLT, located in the Chilean Atacama Desert, and telescopes elsewhere.

    UVES spectrograph mounted on the VLT at the Nasmyth B focus of UT2

    “The ESO Science Archive Facility enabled us to find and use data of the same object obtained in 2002 and 2009,” says Andrea Mehner, a staff astronomer at ESO in Chile who participated in the study. “The comparison of the 2002 high-resolution UVES spectra with our observations obtained in 2019 with ESO’s newest high-resolution spectrograph ESPRESSO was especially revealing, from both an astronomical and an instrumentation point of view.”

    The old data indicated that the star in the Kinman Dwarf could have been undergoing a strong outburst period that likely ended sometime after 2011. Luminous blue variable stars such as this one are prone to experiencing giant outbursts over the course of their life, causing the stars’ rate of mass loss to spike and their luminosity to increase dramatically.

    Based on their observations and models, the astronomers have suggested two explanations for the star’s disappearance and lack of a supernova, related to this possible outburst. The outburst may have resulted in the luminous blue variable being transformed into a less luminous star, which could also be partly hidden by dust. Alternatively, the team says the star may have collapsed into a black hole, without producing a supernova explosion. This would be a rare event: our current understanding of how massive stars die points to most of them ending their lives in a supernova.

    Future studies are needed to confirm what fate befell this star. Planned to begin operations in 2025, ESO’s Extremely Large Telescope (ELT) [below] will be capable of resolving stars in distant galaxies such as the Kinman Dwarf, helping to solve cosmic mysteries such as this one.

    More information

    The team is composed of Andrew Allan (School of Physics, Trinity College Dublin, Ireland [TCD]), Jose J. Groh (TCD), Andrea Mehner (European Southern Observatory, Chile), Nathan Smith (Steward Observatory, University of Arizona, USA [Steward Observatory]), Ioanna Boian (TCD), Eoin Farrell (TCD), Jennifer E. Andrews (Steward Observatory).

    See the full article here .


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    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres


    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov
    Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
  • richardmitnick 12:01 pm on June 1, 2020 Permalink | Reply
    Tags: "Hot stars are plagued by giant magnetic spots ESO data shows", , , , , ESO - European Southern Observatory, ESO data shows, Extreme horizontal branch stars-objects with about half the mass of the Sun but four to five times hotter., Hot stars are plagued by giant magnetic spots   

    From European Southern Observatory: “Hot stars are plagued by giant magnetic spots, ESO data shows” 

    ESO 50 Large

    From European Southern Observatory

    1 June 2020

    Yazan Al Momany
    INAF – Osservatorio Astronomico di Padova
    Padua, Italy
    Tel: +39 333 6297662
    Email: yazan.almomany@inaf.it

    Henri Boffin
    European Southern Observatory
    Garching bei München, Germany
    Email: hboffin@eso.org

    David Jones
    Instituto de Astrofísia de Canarias (IAC)
    Tenerife, Spain
    Tel: +34 63 8982356
    Email: djones@iac.es

    Simone Zaggia
    INAF – Osservatorio Astronomico di Padova
    Padua, Italy
    Tel: +39 (0)49 8293533
    Email: simone.zaggia@inaf.it

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6670
    Cell: +49 151 241 664 00
    Email: pio@eso.org

    1
    Astronomers using European Southern Observatory (ESO) telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters. Not only are these stars plagued by magnetic spots, some also experience superflare events, explosions of energy several million times more energetic than similar eruptions on the Sun. The findings, published today in Nature Astronomy, help astronomers better understand these puzzling stars and open doors to resolving other elusive mysteries of stellar astronomy.Credit: ESO/L. Calçada, INAF-Padua/S. Zaggia

    2
    Spots on extreme horizontal branch stars (right) appear to be quite different from the dark sunspots on our own Sun (left), but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. While sunspots vary in size, a typical size is around an Earth-size planet, 3000 smaller than a giant spot on an extreme horizontal branch star. Credit: ESO/L. Calçada, INAF-Padua/S. Zaggia


    Astronomers using ESO telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters. This video offers a summary of the discovery.The video is available in 4K UHD. The ESOcast Light is a series of short videos bringing you the wonders of the Universe in bite-sized pieces. The ESOcast Light episodes will not be replacing the standard, longer ESOcasts, but complement them with current astronomy news and images in ESO press releases. Credit:ESO
    Directed by: Herbert Zodet.
    Editing: Herbert Zodet.
    Web and technical support: Gurvan Bazin and Raquel Yumi Shida.
    Written by: Stephanie Rowlands, Emma Foxell and Bárbara Ferreira.
    Music: Nuclearmetal/New Horizons — Planetarium.
    Footage and photos: ESO, L. Calçada, INAF-Padua/S. Zaggia, C. Malin ( christophmalin.com ) and B. Tafreshi ( twanight.org ).
    Scientific consultants: Paola Amico and Mariya Lyubenova.

    The team, led by Yazan Momany from the INAF Astronomical Observatory of Padua in Italy, looked at a particular type of star known as extreme horizontal branch stars — objects with about half the mass of the Sun but four to five times hotter. “These hot and small stars are special because we know they will bypass one of the final phases in the life of a typical star and will die prematurely,” says Momany, who was previously a staff astronomer at ESO’s Paranal Observatory in Chile. “In our Galaxy, these peculiar hot objects are generally associated with the presence of a close companion star.”

    Surprisingly, however, the vast majority of these extreme horizontal branch stars, when observed in tightly packed stellar groups called globular clusters, do not appear to have companions. The team’s long-term monitoring of these stars, made with ESO telescopes, also revealed that there was something more to these mysterious objects. When looking at three different globular clusters, Momany and his colleagues found that many of the extreme horizontal branch stars within them showed regular changes in their brightness over the course of just a few days to several weeks.

    “After eliminating all other scenarios, there was only one remaining possibility to explain their observed brightness variations,” concludes Simone Zaggia, a study co-author from the INAF Astronomical Observatory of Padua in Italy and a former ESO Fellow: “these stars must be plagued by spots!”

    Spots on extreme horizontal branch stars appear to be quite different from the dark sunspots on our own Sun, but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. These spots are incredibly persistent, lasting for decades, while individual sunspots are temporary, lasting only a few days to months. As the hot stars rotate, the spots on the surface come and go, causing the visible changes in brightness.

    Beyond the variations in brightness due to spots, the team also discovered a couple of extreme horizontal branch stars that showed superflares — sudden explosions of energy and another signpost of the presence of a magnetic field. “They are similar to the flares we see on our own Sun, but ten million times more energetic,” says study co-author Henri Boffin, an astronomer at ESO’s headquarters in Germany. “Such behaviour was certainly not expected and highlights the importance of magnetic fields in explaining the properties of these stars.”

    After six decades of trying to understand extreme horizontal branch stars, astronomers now have a more complete picture of them. Moreover, this finding could help explain the origin of strong magnetic fields in many white dwarfs, objects that represent the final stage in the life of Sun-like stars and show similarities to extreme horizontal branch stars. “The bigger picture though,” says team member, David Jones, a former ESO Fellow now at the Instituto de Astrofísica de Canarias, Spain, “is that changes in brightness of all hot stars — from young Sun-like stars to old extreme horizontal branch stars and long-dead white dwarfs — could all be connected. These objects can thus be understood as collectively suffering from magnetic spots on their surfaces.”

    To arrive at this result, the astronomers used several instruments on ESO’s Very Large Telescope (VLT) [below], including VIMOS, FLAMES and FORS2, as well as OmegaCAM attached to the VLT Survey Telescope [below] at Paranal Observatory.

    ESO VIMOS on VLT Melipal UT3

    ESO/FLAMES on The VLT. FLAMES is the multi-object, intermediate and high resolution spectrograph of the VLT. Mounted at UT2, FLAMES can access targets over a field of view 25 arcmin in diameter. FLAMES feeds two different spectrograph covering the whole visual spectral range:GIRAFFE and UVES.

    ESO FORS2 VLT mounted on Unit Telescope 1 (Antu)

    ESO OmegaCAM on VST at ESO’s Cerro Paranal observatory,with an elevation of 2,635 metres (8,645 ft) above sea level

    They also employed ULTRACAM on the New Technology Telescope at ESO’s La Silla Observatory [below], also in Chile.

    ESO La Silla NTT ULTRACAM is an ultra fast camera capable of capturing some of the most rapid astronomical events. It can take up to 500 pictures a second in three different colours simultaneously. It was designed and built by scientists from the Universities of Sheffield and Warwick (United Kingdom), in collaboration with the UK Astronomy Technology Centre in Edinburgh. ULTRACAM employs the latest in charged coupled device (CCD) detector technology in order to take, store and analyse data at the required sensitivities and speeds.

    The breakthrough came as the team observed the stars in the near-ultraviolet part of the spectrum, allowing them to reveal the hotter, extreme stars standing out bright amongst the cooler stars in globular clusters.

    More information

    This research is presented in the paper “A plague of magnetic spots among the hot stars of globular clusters”, published today in Nature Astronomy.

    The team is composed of Y. Momany (INAF Astronomical Observatory of Padua, Italy [INAF Padua]), S. Zaggia (INAF Padua), M. Montalto (Department of Physics and Astronomy, University of Padua, Italy [U. Padua]), D. Jones (Instituto de Astrofísica de Canarias and Department of Astrophysics, University of La Laguna, Tenerife, Spain), H.M.J. Boffin (European Southern Observatory, Garching, Germany, S. Cassisi (INAF Astronomical Observatory of Abruzzo and INFN Pisa, Italy), C. Moni Bidin (Instituto de Astronomia, Universidad Catolica del Norte, Antofagasta, Chile), M. Gullieuszik (INAF Padua), I. Saviane (European Southern Observatory, Santiago, Chile), L. Monaco (Departamento de Ciencias Fisicas, Universidad Andreas Bello, Santiago, Chile), E. Mason (INAF Astronomical Observatory of Trieste, Italy), L. Girardi (INAF Padua), V. D’Orazi (INAF Padua), G. Piotto (U. Padua), A.P. Milone (U. Padua), H. Lala (U. Padua), P.B. Stetson (Herzberg Astronomy and Astrophysics, National Research Council, Victoria, Canada), and Y. Beletsky (Las Campanas Observatory, Carnegie Institution of Washington, La Serena, Chile).

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Bloc Icon

    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/Cerro LaSilla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres

    ESO VLT at Cerro Paranal in the Atacama Desert

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).


    ESO APEXESO/MPIfR APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)at the Llano de Chajnantor Observatory in the Atacama desert.

    A novel gamma ray telescope under construction on Mount Hopkins, Arizona. a large project known as the Čerenkov
    Telescope Array, composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison, and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev

     
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