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  • richardmitnick 9:45 am on May 20, 2016 Permalink | Reply
    Tags: , , ESO VLT, Stellar cannibalism transforms star into brown dwarf,   

    From Southampton: “Stellar cannibalism transforms star into brown dwarf” 

    U Southampton bloc

    University of Southampton

    19 May 2016
    No writer credit found

    1
    The white dwarf (right) stripping mass from the brown dwarf.

    Astronomers have detected a sub-stellar object that used to be a star, after being consumed by its white dwarf companion.

    An international team of astronomers made the discovery by observing a very faint binary system, J1433 which is located 730 light-years away. The system consists of a low-mass object – about 60 times the mass of Jupiter – in an extremely tight 78-minute orbit around a white dwarf (the remnant of a star like our Sun).

    Due to their close proximity, the white dwarf strips mass from its low-mass companion. This process has removed about 90 per cent of the mass of the companion, turning it from a star into a brown dwarf.

    Artist's concept of a Brown dwarf [not quite a] star. NASA/JPL-Caltech
    Artist’s concept of a Brown dwarf [not quite a] star. NASA/JPL-Caltech

    Most brown dwarfs are ‘failed stars’, objects that were born with too little mass to shine brightly by fusing hydrogen in their cores. By contrast, the brown dwarf in this system was born as a full-fledged star, but has been stripped to its current mass by billions of years of stellar cannibalism.

    The study, published* in the journal Nature, used the X-Shooter instrument at the Very Large Telescope (VLT) in Cerro Paranal, Chile, in order to directly detect and characterise a system that has survived such a traumatic transition.

    ESO/VLT at Cerro Paranal, Chile
    ESO/VLT at Cerro Paranal, Chile

    ESO X-shooter on VLT at Cerro Paranal, Chile

    ESO X-shooter on VLT at Cerro Paranal, Chile

    Lead author Juan Venancio Hernández Santisteban, a PhD student at the University of Southampton, said: “X-Shooter is a unique instrument that can observe astronomical objects simultaneously all the way from the ultraviolet to the infrared. This allowed us to dissect the light of this system and uncover the hidden signal from the faint brown dwarf.

    “Our knowledge of binary evolution suggests that, if the companion star can survive the transition, brown dwarfs should be common in this type of system. However, despite several efforts, only a few candidate systems with tentative evidence for brown-dwarf companions had previously been found. Our results now confirm that the successful transformation of a star to a brown dwarf is indeed possible.”

    The astronomers also used their data to map the surface temperature across the brown dwarf. This turns out to be non-uniform, since this cool sub-stellar object is strongly irradiated by its much hotter white dwarf companion. The map shows a clear temperature difference between the dayside (the side facing the white dwarf) and the nightside. On average, the difference amounts to 57 degrees Celsius, but the hottest and coldest parts of the brown dwarf’s surface differ by a full 200 degrees Celsius.

    Professor Christian Knigge, from the University of Southampton who initiated and supervised the project, said: “The construction of this surface temperature map is a significant achievement. In many giant planets – the so-called ‘hot-Jupiters’ – irradiation by the host star completely overwhelms the planet’s internal heat flux. By contrast, internal heat flux and external irradiation are comparable for the brown dwarf in our study. This represents an unexplored regime, making such systems valuable as laboratories for irradiated (sub-) stellar and planetary atmospheres.”

    The study involved astronomers from the universities of Keele, Manchester, Oxford, Sheffield, Southampton and Warwick (UK), the Instituto de Astrofísica de Canarias (Spain) and Hamburger Sternwarte (Germany). It was funded by the Royal Astronomical Society, European Union Eleventh Framework Programme, European Research Council, CONACyT (Mexico) and the University of Southampton.

    *Science paper:
    An irradiated brown-dwarf companion to an accreting white dwarf

    See the full article here .

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    The University of Southampton is a world-class university built on the quality and diversity of our community. Our staff place a high value on excellence and creativity, supporting independence of thought, and the freedom to challenge existing knowledge and beliefs through critical research and scholarship. Through our education and research we transform people’s lives and change the world for the better.

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    Since publication of the previous University Strategy in 2010 we have achieved much of what we set out to do against a backdrop of a major economic downturn and radical change in higher education in the UK.

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  • richardmitnick 1:54 pm on May 18, 2016 Permalink | Reply
    Tags: , , ESO VLT, LHA 120-N55 gas cloud   

    From ESO: “A Beautiful Instance of Stellar Ornamentation” 

    ESO 50 Large

    European Southern Observatory

    18 May 2016
    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1

    In this image from ESO’s Very Large Telescope (VLT), light from blazing blue stars energises the gas left over from the stars’ recent formation. The result is a strikingly colourful emission nebula, called LHA 120-N55, in which the stars are adorned with a mantle of glowing gas. Astronomers study these beautiful displays to learn about the conditions in places where new stars develop.

    LHA 120-N55, or N55 as it is usually known, is a glowing gas cloud in the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way located about 163 000 light-years away.

    Large Magellanic Cloud. Adrian Pingstone  December 2003
    Large Magellanic Cloud. Adrian Pingstone December 2003

    N55 is situated inside a supergiant shell, or superbubble called LMC 4. Superbubbles, often hundreds of light-years across, are formed when the fierce winds from newly formed stars and shockwaves from supernova explosions work in tandem to blow away most of the gas and dust that originally surrounded them and create huge bubble-shaped cavities.

    The material that became N55, however, managed to survive as a small remnant pocket of gas and dust. It is now a standalone nebula inside the superbubble and a grouping of brilliant blue and white stars — known as LH 72 — also managed to form hundreds of millions of years after the events that originally blew up the superbubble. The LH 72 stars are only a few million years old, so they did not play a role in emptying the space around N55. The stars instead represent a second round of stellar birth in the region.

    The recent rise of a new population of stars also explains the evocative colours surrounding the stars in this image. The intense light from the powerful, blue–white stars is stripping nearby hydrogen atoms in N55 of their electrons, causing the gas to glow in a characteristic pinkish colour in visible light. Astronomers recognise this telltale signature of glowing hydrogen gas throughout galaxies as a hallmark of fresh star birth.

    While things seem quiet in the star-forming region of N55 for now, major changes lie ahead. Several million years hence, some of the massive and brilliant stars in the LH 72 association will themselves go supernova, scattering N55’s contents. In effect, a bubble will be blown within a superbubble, and the cycle of starry ends and beginnings will carry on in this close neighbour of our home galaxy.

    This new image was acquired using the FOcal Reducer and low dispersion Spectrograph (FORS2) instrument attached to ESO’s VLT.

    ESO FORS1
    FORS

    It was taken as part of 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.

    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO LaSilla
    LaSilla

    ESO VLT
    VLT

    ESO Vista Telescope
    VISTA

    ESO NTT
    NTT

    ESO VLT Survey telescope
    VLT Survey Telescope

    ALMA Array
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  • richardmitnick 1:51 pm on April 29, 2016 Permalink | Reply
    Tags: Asteroid C/2014 S3 (PANSTARRS), , , ESO VLT   

    From ESO: “Unique Fragment from Earth’s Formation Returns after Billions of Years in Cold Storage” 

    ESO 50 Large

    European Southern Observatory

    29 April 2016
    Karen Meech
    Institute for Astronomy, University of Hawai`i
    Honolulu, HI, USA
    Tel: +1 808 956 6828
    Cell: +1 720 231 7048
    Email: meech@ifa.hawaii.edu

    Olivier Hainaut
    ESO Astronomer
    Garching bei München, Germany
    Tel: +49 89 3200 6752
    Cell: +49 151 2262 0554
    Email: ohainaut@eso.org

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Tailless Manx comet from Oort Cloud brings clues about the origin of the Solar System

    1

    Astronomers have found a unique object that appears to be made of inner Solar System material from the time of Earth’s formation, which has been preserved in the Oort Cloud far from the Sun for billions of years. Observations with ESO’s Very Large Telescope, and the Canada France Hawai`i Telescope, show that C/2014 S3 (PANSTARRS) is the first object to be discovered on a long-period cometary orbit that has the characteristics of a pristine inner Solar System asteroid.

    CFHT Telescope, Mauna Kea, Hawaii, USA
    CFHT Interior
    CFHT Telescope, Mauna Kea, Hawaii, USA

    It may provide important clues about how the Solar System formed.

    In a paper* to be published today in the journal Science Advances, lead author Karen Meech of the University of Hawai`i’s Institute for Astronomy and her colleagues conclude that C/2014 S3 (PANSTARRS) formed in the inner Solar System at the same time as the Earth itself, but was ejected at a very early stage.

    Their observations indicate that it is an ancient rocky body, rather than a contemporary asteroid that strayed out. As such, it is one of the potential building blocks of the rocky planets, such as the Earth, that was expelled from the inner Solar System and preserved in the deep freeze of the Oort Cloud for billions of years [1].

    Karen Meech explains the unexpected observation: “We already knew of many asteroids, but they have all been baked by billions of years near the Sun. This one is the first uncooked asteroid we could observe: it has been preserved in the best freezer there is.”

    C/2014 S3 (PANSTARRS) was originally identified by the Pan-STARRS1 telescope as a weakly active comet a little over twice as far from the Sun as the Earth.

    Pann-STARSR1 Telescope
    Pann-STARRS1 interior
    Pann-STARRS1 Telescope, U Hawaii, Mauna Kea, Hawaii, USA

    Its current long orbital period (around 860 years) suggests that its source is in the Oort Cloud, and it was nudged comparatively recently into an orbit that brings it closer to the Sun.

    Oort cloud Image by TypePad, http://goo.gl/NWlQz6
    Oort cloud Image by TypePad, http://goo.gl/NWlQz6

    The team immediately noticed that C/2014 S3 (PANSTARRS) was unusual, as it does not have the characteristic tail that most long-period comets have when they approach so close to the Sun. As a result, it has been dubbed a Manx comet, after the tailless cat. Within weeks of its discovery, the team obtained spectra of the very faint object with ESO’s Very Large Telescope in Chile.

    Careful study of the light reflected by C/2014 S3 (PANSTARRS) indicates that it is typical of asteroids known as S-type, which are usually found in the inner asteroid main belt. It does not look like a typical comet, which are believed to form in the outer Solar System and are icy, rather than rocky. It appears that the material has undergone very little processing, indicating that it has been deep frozen for a very long time. The very weak comet-like activity associated with C/2014 S3 (PANSTARRS), which is consistent with the sublimation of water ice, is about a million times lower than active long-period comets at a similar distance from the Sun.

    The authors conclude that this object is probably made of fresh inner Solar System material that has been stored in the Oort Cloud and is now making its way back into the inner Solar System.

    A number of theoretical models are able to reproduce much of the structure we see in the Solar System. An important difference between these models is what they predict about the objects that make up the Oort Cloud. Different models predict significantly different ratios of icy to rocky objects. This first discovery of a rocky object from the Oort Cloud is therefore an important test of the different predictions of the models. The authors estimate that observations of 50–100 of these Manx comets are needed to distinguish between the current models, opening up another rich vein in the study of the origins of the Solar System.

    Co-author Olivier Hainaut (ESO, Garching, Germany), concludes: “We’ve found the first rocky comet, and we are looking for others. Depending how many we find, we will know whether the giant planets danced across the Solar System when they were young, or if they grew up quietly without moving much.”
    Notes

    [1] The Oort cloud is a huge region surrounding the Sun like a giant, thick soap bubble. It is estimated that it contains trillions of tiny icy bodies. Occasionally, one of these bodies gets nudged and falls into the inner Solar System, where the heat of the sun turns it into a comet. These icy bodies are thought to have been ejected from the region of the giant planets as these were forming, in the early days of the Solar System.

    More information

    *This research was presented in a paper entitled Inner Solar System Material Discovered in the Oort Cloud, by Karen Meech et al., in the journal Science Advances.

    The team is composed of Karen J. Meech (Institute for Astronomy, University of Hawai`i, USA), Bin Yang (ESO, Santiago, Chile), Jan Kleyna (Institute for Astronomy, University of Hawai`i, USA), Olivier R. Hainaut (ESO, Garching, Germany), Svetlana Berdyugina (Institute for Astronomy, University of Hawai’i, USA; Kiepenheuer Institut für Sonnenphysik, Freiburg, Germany), Jacqueline V. Keane (Institute for Astronomy, University of Hawai`i, USA), Marco Micheli (ESA, Frascati, Italy), Alessandro Morbidelli (Laboratoire Lagrange/Observatoire de la Côte d’Azur/CNRS/Université Nice Sophia Antipolis, France) and Richard J. Wainscoat (Institute for Astronomy, University of Hawai`i, USA).

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

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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 LaSilla
    LaSilla

    ESO VLT
    VLT

    ESO Vista Telescope
    VISTA

    ESO NTT
    NTT

    ESO VLT Survey telescope
    VLT Survey Telescope

    ALMA Array
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    ESO E-ELT
    E-ELT

    ESO APEX
    Atacama Pathfinder Experiment (APEX) Telescope

     
  • richardmitnick 4:31 am on April 27, 2016 Permalink | Reply
    Tags: , , , ESO VLT, Four Lasers Over Paranal   

    From ESO: “Four Lasers Over Paranal” 

    ESO 50 Large

    European Southern Observatory

    27 April 2016
    Domenico Bonaccini Calia
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6567
    Cell: +49 (0) 174 5246 013
    Email: Domenico.Bonaccini@eso.org

    Wolfgang Hackenberg
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6782
    Email: whackenb@eso.org

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1

    On 26 April 2016 ESO’s Paranal Observatory in Chile hosted an event to mark the first light for the four powerful lasers that form a crucial part of the adaptive optics systems on ESO’s Very Large Telescope. Attendees were treated to a spectacular display of cutting-edge laser technology against the majestic skies of Paranal. These are the most powerful laser guide stars ever used for astronomy and the event marks the first use of multiple laser guide stars at ESO.

    2
    Schematic view of the Four Laser Guide Star Facility on the ESO VLT

    3
    The most powerful laser guide star system in the world sees first light at the Paranal Observatory

    ESO staff were present for the event, along with senior representatives of the companies that have manufactured the different components of the new system.

    The Four Laser Guide Star Facility (4LGSF) shines four 22-watt laser beams into the sky to create artificial guide stars by making sodium atoms in the upper atmosphere glow so that they look just like real stars [1]. The artificial stars allow the adaptive optics systems to compensate for the blurring caused by the Earth’s atmosphere and so that the telescope can create sharp images. Using more than one laser allows the turbulence in the atmosphere to be mapped in far greater detail to significantly improve the image quality over a larger field of view.

    The Four Laser Guide Star Facility is an example of how ESO enables European industry to lead complex research and development projects. The fibre laser used by the 4LGSF is also one of the most successful transfers of ESO technology to industry.

    TOPTICA, the German main contractor, was responsible for the laser system and provided the oscillator, the frequency doubler, and the system control software. Wilhelm Kaenders, president of TOPTICA, said: “TOPTICA has enjoyed the collaboration with ESO tremendously. It is not only the personal thrill of being engaged with astronomy, an old passion, again, and working with very clever ESO technologists; it is also the inspiration that we have received for our own commercial product development.” [2]

    MPBC of Canada provided the fibre laser pumps and Raman amplifiers, which are based on an ESO licensed patent. Jane Bachynski, President of MPB Communications Inc. said: “MPBC is proud to have worked with ESO in the development of Raman fibre amplifiers to much higher powers, allowing MPBC to bring this technology to the stars. This event marks the culmination of many years of hard work on behalf of all involved.” [3]

    TNO in the Netherlands manufactured the optical tube assemblies, which expand the laser beams and direct them into the sky. Paul de Krom, CEO of TNO, said: “TNO valued the cooperative working environment during the development of the optical tube assemblies and looks forward to the opportunity to work with ESO and the other partners in the 4LGSF project in the future.” [4]

    The 4LGSF is part of the Adaptive Optics Facility on Unit Telescope 4 of the VLT, designed specifically to provide the adaptive optics systems GALACSI/MUSE and GRAAL/HAWK-I with four sodium laser guide stars. With this new facility, Paranal Observatory continues to have the most advanced and the largest number of adaptive optics systems in operation today.

    The 4LGSF lasers were developed by ESO with industry and have already been procured, among others, by the Keck Observatory (which contributed to the industrial laser development cost along with the European Commission) and the Subaru Telescope. In the future these industrial lasers will also feature on the telescopes at the Gemini Observatory and will be the preferred choice for several other observatories and extremely large telescope projects.

    The new techniques developed for the Four Laser Guide Star Facility pave the way for the adaptive optics system of the European Extremely Large Telescope (E-ELT), the world’s biggest eye on the sky.
    Notes

    [1] The 4LGSF is the second generation laser guide star facility, built by ESO for the Adaptive Optics Facility on the UT4 VLT telescope. The two critical long-lead items for the 4LGSF, the laser system and the optical tube assemblies for the laser launch telescope systems have been procured from industry. The fibre Raman laser technology, on which the 4LGSF laser system is based, has been developed at ESO, patented and licensed to industry.

    [2] This project has allowed TOPTICA to extend its products into a new wavelength and output power regime. It now produces the SodiumStar 20/2, which is recognised as a quasi-standard for existing and planned telescopes around the world. All next generation extremely large telescope projects, for example, use the SodiumStar laser as their baseline. During the seven years of collaboration with ESO the company has grown from 80 people to more than 200 today.

    [3] MPBC’s collaboration with ESO has also generated an additional benefit, in the form of an offshoot product line of single frequency amplification products at virtually any wavelength, supporting novel applications for the scientific and commercial research community.

    [4] The developments by TNO also involved contributions from many suppliers from the Netherlands (Vernooy, Vacutech, Rovasta, Schott Benelux, Maxon Motor Benelux, IPS technology, Sensordata and WestEnd) and other international companies (RMI, Qioptiq, Laser Components, Carl Zeiss, GLP, Faes, Farnell, Eriks and Pfeiffer). The knowledge and technologies advanced by working with ESO feed into TNO’s Dutch and European partners, in fields including astronomy, communications, semiconductor manufacturing, medical devices, space science and Earth observation.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

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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 LaSilla
    LaSilla

    ESO VLT
    VLT

    ESO Vista Telescope
    VISTA

    ESO NTT
    NTT

    ESO VLT Survey telescope
    VLT Survey Telescope

    ALMA Array
    ALMA

    ESO E-ELT
    E-ELT

    ESO APEX
    Atacama Pathfinder Experiment (APEX) Telescope

     
  • richardmitnick 3:14 pm on April 15, 2016 Permalink | Reply
    Tags: , , ESO VLT, GALACSI Adaptive Optics System for VLT on YEPUN with MUSE   

    From ESO: “GALACSI Adaptive Optics System Ready to be Mounted on the VLT” 

    ESO 50 Large

    European Southern Observatory

    15 April 2016
    Robin Arsenault
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6524
    Email: rarsenau@eso.org

    Peter Grimley
    ESO, Assistant Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6383
    Email: pgrimley@eso.org

    GALACSI Adaptive Optics System for VLT
    The GALACSI adaptive optics module, built by ESO’s engineers at its headquarters in Garching, Germany, has been thoroughly tested and has passed with flying colours. It will be shipped to Chile later this year to be fitted to ESO’s Very Large Telescope (VLT) on Yepun (UT4) with MUSE, on Cerro Paranal.

    GALACSI is a part of the adaptive optics system which will significantly increase the performance of the MUSE instrument, a panoramic integral-field spectrograph working at visible wavelengths. The MUSE instrument and the GALACSI system together will be known as the MUSE facility. Adding GALACSI to MUSE will essentially double the amount of energy in each image pixel, providing astronomers with a much more powerful tool. As well as bringing about a huge improvement in the VLT’s capabilities, GALACSI and the other elements of the adaptive optics system are advancing technology that will be used on the forthcoming European Extremely Large Telescope.

    Adaptive optics systems compensate for the effects of atmospheric turbulence, which degrades images obtained by ground-based telescopes. When it passes through the atmosphere, light from a celestial object gets jiggled around, meaning that the telescope sees a blurred image. GALACSI will rely on 4 sodium lasers launched from the centre of one of the Unit Telescopes of the VLT to produce “artificial stars”, known as guide stars. Sensors then follow the motion of these guide stars as the light from them flickers in the turbulent atmosphere. That allows a computer to calculate the correction that must be applied to the telescope’s deformable secondary mirror (itself a new addition to the VLT) to compensate for the atmospheric disturbance. In this way, extremely sharp images of the real celestial objects can be obtained.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO LaSilla
    LaSilla

    ESO VLT
    VLT

    ESO Vista Telescope
    VISTA

    ESO NTT
    NTT

    ESO VLT Survey telescope
    VLT Survey Telescope

    ALMA Array
    ALMA

    ESO E-ELT
    E-ELT

    ESO APEX
    Atacama Pathfinder Experiment (APEX) Telescope

     
  • richardmitnick 3:58 pm on December 15, 2015 Permalink | Reply
    Tags: , , ESO VLT,   

    From ESO: “Mind the Gap” 

    [I picked this up from 2008 because it relates to an ALMA release due out on 12.16.15.]


    European Southern Observatory

    8 September 2008
    Klaus Pontoppidan
    California Institute of Technology
    Pasadena, USA
    Tel: +1 626 395 4900
    Cell: +1 626 679 5793
    Email: pontoppi@gps.caltech.edu

    Ewine van Dishoeck
    Leiden University
    Leiden, Netherlands
    Tel: +31 71 527 58 14
    Email: ewine@strw.leidenuniv.nl

    VLT instrument hints at the presence of planets in young gas discs

    1

    Astronomers have been able to study planet-forming discs around young Sun-like stars in unsurpassed detail, clearly revealing the motion and distribution of the gas in the inner parts of the disc. This result, which possibly implies the presence of giant planets, was made possible by the combination of a very clever method enabled by ESO’s Very Large Telescope.

    Planets could be home to other forms of life, so the study of exoplanets ranks very high in contemporary astronomy. More than 300 planets are already known to orbit stars other than the Sun, and these new worlds show an amazing diversity in their characteristics. But astronomers don’t just look at systems where planets have already formed – they can also get great insights by studying the discs around young stars where planets may currently be forming. “This is like going 4.6 billion years back in time to watch how the planets of our own Solar System formed,” says Klaus Pontoppidan from Caltech, who led the research.

    Pontoppidan and colleagues have analysed three young analogues of our Sun that are each surrounded by a disc of gas and dust from which planets could form. These three discs are just a few million years old and were known to have gaps or holes in them, indicating regions where the dust has been cleared and the possible presence of young planets.

    The new results not only confirm that gas is present in the gaps in the dust, but also enable astronomers to measure how the gas is distributed in the disc and how the disc is oriented. In regions where the dust appears to have been cleared out, molecular gas is still highly abundant. This can either mean that the dust has clumped together to form planetary embryos, or that a planet has already formed and is in the process of clearing the gas in the disc.

    For one of the stars, SR 21, a likely explanation is the presence of a massive giant planet orbiting at less than 3.5 times the distance between the Earth and the Sun, while for the second star, HD 135344B, a possible planet could be orbiting at 10 to 20 times the Earth-Sun distance. The observations of the third star, TW Hydrae, may also require the presence of one or two planets.

    “Our observations with the CRIRES instrument on ESO’s Very Large Telescope clearly reveal that the discs around these three young, Sun-like stars are all very different and will most likely result in very different planetary systems,” concludes Pontoppidan.

    ESO CRIRES
    CRIRES

    “Nature certainly does not like to repeat herself” [1].

    “These kinds of observations complement the future work of the ALMA observatory, which will be imaging these discs in great detail and on a larger scale,” adds Ewine van Dishoeck, from Leiden Observatory, who works with Pontoppidan.

    To study the gaps in dust discs that are the size of the Solar System around stars that are located up to 400 light-years away is a daunting challenge that requires a clever solution and the best possible instruments [2].

    “Traditional imaging cannot hope to see details on the scale of planetary distances for objects located so far away,” explains van Dishoeck. “Interferometry can do better but won’t allow us to follow the motion of the gas.”

    Astronomers used a technique known as spectro-astrometric imaging to give them a window into the inner regions of the discs where Earth-like planets may be forming. They were able not only to measure distances as small as one-tenth the Earth-Sun distance, but to measure the velocity of the gas at the same time [3].

    “The particular configuration of the instrument and the use of adaptive optics allows astronomers to carry out observations with this technique in a very user-friendly way: as a consequence, spectro-astrometric imaging with CRIRES can now be routinely performed,” says team member Alain Smette, from ESO [4].

    Notes

    Pontoppidan, K. M. et. al. 2008, Spectro-Astrometric Imaging of Molecular Gas Within Protoplanetary Disk Gaps, Astrophysical Journal, 684, 1323, 10 September 2008. Team members are Klaus M. Pontoppidan, Geoffrey A. Blake, and Michael J. Ireland (California Institute of Technology, Pasadena, USA), Ewine F. van Dishoeck (Leiden Observatory, The Netherlands, and Max-Planck-Institute for Extraterrestrial Physics, Garching, Germany – MPE), Alain Smette (ESO, Chile), and Joanna Brown (MPE).

    [1] The discs are about an hundred astronomical units (AU – the mean distance between the Earth and the Sun, or 149.6 million kilometres) across, but the stars are more than 200 light-years away (one light-year is 200 000 AU). To resolve structures on 1 AU scales in these systems corresponds to reading the license plate on a car at a distance of 2000 km – roughly the distance from Stockholm to Lisbon.

    [2] CRIRES, the near-infrared spectrograph attached to ESO’s Very Large Telescope, is fed from the telescope through an adaptive optics module which corrects for the blurring effect of the atmosphere and so makes it possible to have a very narrow slit with a high spectral dispersion: the slit width is 0.2 arcsecond and the spectral resolution is 100 000. Using spectro-astrometry, an ultimate spatial resolution of better than 1 milli-arcsecond is achieved.

    [3] The core of the spectro-astrometry imaging technique relies on the ability of CRIRES to be positioned very precisely on the sky, while retaining the ability to spread the light into a spectrum so that wavelength differences of 1 part in 100 000 can be detected. More precisely, the astronomers measure the centroid in the spatial direction of a spectrally resolved emission line: effectively, astronomers take a sharp emission line – a clear fingerprint of a molecule in the gas – and use data from several slit positions to locate the sources of particular emission lines, and hence to map the distribution of the gas with much greater precision than can be achieved by straightforward imaging. The astronomers have obtained spectra of the discs centred at wavelengths of 4.715 microns at 6 different position angles.

    [4] Alain Smette is the CRIRES Instrument Scientist.

    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO LaSilla
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  • richardmitnick 10:16 am on December 9, 2015 Permalink | Reply
    Tags: , , ESO VLT, NGC 5291   

    From ESO: “VLT Revisits a Curious Cosmic Collision” 


    European Southern Observatory

    9 December 2015
    Jérémy Fensch
    Laboratoire AIM Paris-Saclay, CEA/IRFU/SAp, Universite Paris Diderot
    Gif-sur-Yvette, France
    Email: jeremy.fensch@gmail.com

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1

    The spectacular aftermath of a 360 million year old cosmic collision is revealed in great detail in new images from ESO’s Very Large Telescope at the Paranal Observatory. Among the debris is a rare and mysterious young dwarf galaxy. This galaxy is providing astronomers with an excellent opportunity to learn more about similar galaxies that are expected to be common in the early Universe, but are normally too faint and distant to be observed by current telescopes.

    NGC 5291, the hazy, golden oval dominating the centre of this image, is an elliptical galaxy located nearly 200 million light-years away in the constellation of Centaurus (The Centaur). Over 360 million years ago, NGC 5291 was involved in a dramatic and violent collision as another galaxy travelling at immense speeds barrelled into its core. The cosmic crash ejected huge streams of gas into nearby space, which later coalesced into a ring formation around NGC 5291 [1].

    Over time, material in this ring gathered and collapsed into dozens of star-forming regions and several dwarf galaxies, revealed as pale blue and white regions scattered around NGC 5291 in this new image from the FORS instrument, mounted on the VLT.

    ESO FORS1
    FORS

    The most massive and luminous clump of material, to the right of NGC 5291, is one of these dwarf galaxies and is known as NGC 5291N.

    The Milky Way, like all large galaxies, is believed to have formed through the build-up of smaller dwarf galaxies in the early years of the Universe. These small galaxies, if they have survived on their own up to the present day, now normally contain many extremely old stars.

    Yet NGC 5291N appears to contain no old stars. Detailed observations with the MUSE spectrograph [2] also found that the outer parts of the galaxy had properties typically associated with the formation of new stars, but what was observed is not predicted by current theoretical models. Astronomers suspect that these unusual aspects may be the result of massive collisions of gas in the region.

    ESO MUSE
    MUSE

    NGC 5291N doesn’t look like a typical dwarf galaxy, but instead it shares a striking number of similarities with the clumpy structures present within many of the star-forming galaxies in the distant Universe. This makes it a unique system in our local Universe and an important laboratory for the study of early gas-rich galaxies, which are normally much too distant to be observed in detail by current telescopes.

    This unusual system has previously been observed by a wide range of ground-based facilities, including ESO’s 3.6-metre telescope at the La Silla Observatory [3].

    ESO 3.6m telescope & HARPS at LaSilla
    3.6 meter telescope at LaSilla

    However, the capabilities of MUSE, FORS and the Very Large Telescope have only now allowed some of the history and properties of NGC 5291N to be determined.

    Future observations, including those by ESO’s European Extremely Large Telescope (E-ELT), may allow astronomers to further unravel this dwarf galaxy’s remaining mysteries.

    ESO E-ELT
    Future E-ELT

    Notes

    [1] NGC 5291 is currently also interacting more gently with MCG-05-33-005 — or the Seashell Galaxy — the unusual comma-shaped galaxy appearing to leech off NGC 5291’s luminous core.

    3
    Seashell Galaxy

    [2] NGC 5291N was observed using integral field spectrography during MUSE’s first Science Verification run. Integral field spectrography collects a spectrum at every point on the sky, providing a powerful three-dimensional view of the target. The MUSE observations revealed unexpected oxygen and hydrogen emission lines in the outskirts of NGC 5291N.

    [3] NGC 5291 was studied by astronomers using ESO’s 3.6-metre telescope at the La Silla Observatory back in 1978. These observations revealed large amounts of material in the intergalactic space around the galaxy, which we now know to be the star-forming regions and several dwarf galaxies created from the collapse of the galaxy’s gaseous ring.

    More information

    This research was presented in a paper entitled “Ionization processes in a local analogue of distant clumpy galaxies: VLT MUSE IFU spectroscopy and FORS deep images of the TDG NGC 5291N”, by J. Fensch et al., to appear in the journal Astronomy & Astrophysics.

    The team is composed of J. Fensch (Laboratoire AIM Paris-Saclay, CEA/IRFU/SAp, Universite Paris Diderot, Gif-sur-Yvette, France [CEA]), P.-A. Duc (CEA) , P. M. Weilbacher (Leibniz-Institut für Astrophysik, Potsdam, Germany), M. Boquien (University of Cambridge, United Kingdom; Universidad de Antofagasta, Antofagasta, Chile) and E. Zackrisson (Uppsala University, Uppsala, Sweden).

    Research paper

    Another view of NGC 5291
    2
    A image of en:NGC 5291 by the Spitzer Space Telescope

    NASA Spitzer Telescope
    NASA/Spitzer

    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

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  • richardmitnick 9:52 am on December 7, 2015 Permalink | Reply
    Tags: , , ESO VLT,   

    From Hubble: “Hubblecast 88 Mysterious Ripples Found Racing Through Planet-forming Disc” 

    NASA Hubble Telescope

    Hubble

    Using images from the NASA/ESA Hubble Space Telescope and ESO’s Very Large Telescope, astronomers have discovered unique and totally unexpected structures within the dusty disc around the star AU Microscopii.


    download mp4 video here.

    ESO VLT Interferometer
    ESO VLT

    See the full article here .

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    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 12:13 pm on November 27, 2015 Permalink | Reply
    Tags: , , , ESO VLT   

    From ESO: “Laser Guide Star Units Accepted and Shipped to Chile” 


    European Southern Observatory

    27 November 2015
    Domenico Bonaccini Calia
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6567
    Email: dbonacci@eso.org

    Wolfgang Hackenberg
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6782
    Email: whackenb@eso.org

    Richard Hook
    ESO, Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1
    One of the units of the Four Laser Guide Star Facility for the VLT

    All four laser guide star units that form the Four Laser Guide Star Facility — a core part of the Adaptive Optics Facility (AOF) for ESO’s Very Large Telescope — have now been accepted and are being shipped to Chile. This is a major step towards establishing VLT Unit Telescope 4 as a fully adaptive telescope with much enhanced image quality.

    ESO 4LGSF Adaptive Optics Facility (AOF)
    The 4LGSF is to be installed as a subsystem of the Adaptive Optics Facility (AOF) on UT4 of the VLT, to provide the AO systems GALACSI/MUSE and GRAAL/HAWK-I with four sodium laser guide stars (LGSs), as artificial reference sources for the high-order AO corrections.

    The 4LGSF will deploy four modular LGS Units (see below) at the UT4 Centrepiece, as shown in Figure 1. Each LGS Unit consists of the Launch Telescope System incl. 20W Laser Head and two close-by cabinets, one hosting the Laser Unit electronics (incl. the pump fibre laser unit) and the other containing the local control electronics. Two additional 4LGSF cabinets are installed on a new 4LGSF Platform underneath the Nasmyth B platform and contain the computers for independently controlling the four LGS Units. The 4LGSF Platform also hosts the heat exchanger for the laser cooling system.

    An adaptive optics system uses sensors to analyse the atmospheric turbulence and a deformable mirror integrated in the telescope to correct for the image distortions caused by the atmosphere. But a bright point-like star very close in the sky to the object being studied is essential, so that the turbulence can be accurately characterised.

    Finding a natural star in the right place for this role is unlikely. So, to make the correction of the atmospheric turbulence possible everywhere in the sky, for all possible science targets, an artificial star is needed. Such stars can be created by projecting a powerful laser beam into the sky onto the sodium layer, where it creates a bright glow that appears star-like from the ground.

    By measuring the atmospherically induced motions and distortions of this artificial star, and making tiny adjustments to the deformable secondary mirror one thousand times per second, the telescope can produce images with much greater sharpness than is possible without adaptive optics.

    The first Adaptive Optics Facility laser guide star unit was installed on the VLT and successfully tested in situ earlier this year. These tests have confirmed the sound design implemented by ESO, in collaboration with European industry and scientific institutes [1]. Tests on VLT Unit Telescope 4 in Chile showed high optical quality, providing an almost perfect artificial star image, and high efficiency of the sodium layer excitation. These successes mean that the team can proceed with preliminary tests with GRAAL, the adaptive optics module feeding HAWK-I, the wide-field imager on Unit Telescope 4; all further steps towards the full commissioning of the Adaptive Optics Facility at Paranal.

    ESO Graal
    GRAAL

    ESO HAWK-I
    Hawk-I

    The Adaptive Optics Facility will use four lasers simultaneously, which will allow better characterisation of the atmosphere’s properties — and hence a larger field of view where the image is corrected — than is possible with just one laser.

    When fully installed, the Adaptive Optics Facility will feed light into two instruments, HAWK-I (in conjunction with GRAAL) and the integral field spectrograph, MUSE, (in conjunction with GALACSI).

    ESO MUSE
    MUSE

    ESO GALACSI
    GALACSI

    Notes

    [1] The companies involved include: TOPTICA, Germany; TNO, The Netherlands; MPB Communications, Canada; Optec, Italy; Astrel, Italy; and Laseroptik, Germany. In addition INAF–Osservatorio di Roma, Italy has made significant contributions to the project.

    Links

    More information about the laser
    More information about the deformable secondary mirror
    More information about the laser launch telescope

    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO LaSilla
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  • richardmitnick 4:55 pm on November 25, 2015 Permalink | Reply
    Tags: , , , ESO VLT   

    From ESO: “MUSE Observations Enable Prediction of Once-in-a-lifetime Supernova Replay” 


    European Southern Observatory

    25 November 2015
    Claudio Grillo
    Dark Cosmology Centre, Niels Bohr Institute
    University of Copenhagen, Denmark
    Email: grillo@dark-cosmology.dk

    Piero Rosati
    Department of Physics and Earth Science
    University of Ferrara
    Email: rosati@fe.infn.it

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1

    Astronomers have used the Multi Unit Spectroscopic Explorer (MUSE), attached to ESO’s Very Large Telescope (VLT) at the Paranal Observatory, to take advantage of a once-in-a-lifetime opportunity to test their understanding of massive clusters of galaxies. They are making the first ever prediction of an observational event in the distant Universe before it actually becomes visible.

    Images of the galaxy cluster MACS J1149+2223, taken by the NASA/ESA Hubble Space Telescope in November 2014, revealed a distant exploding star — a supernova — like no other ever seen. Nicknamed Refsdal [1], it is the first supernova to be split into four separate images through the process of gravitational lensing, forming an almost perfect Einstein Cross around one of the cluster’s galaxies.

    ESO MUSE
    MUSE

    2
    The European Space Agency’s Faint Object Camera on board NASA’s Hubble Space Telescope has provided astronomers with the most detailed image ever taken of the gravitational lens G2237 + 0305 — sometimes referred to as the Einstein Cross. The photograph shows four images of a very distant quasar which has been multiple-imaged by a relatively nearby galaxy acting as a gravitational lens. The angular separation between the upper and lower images is 1.6 arcseconds.
    Date 13 September 1990

    Gravitational lensing is a consequence of [Albert] Einstein’s theory of general relativity. The paper stating the equations of this fundamental change in our understanding of gravity was published on 25 November 1915, exactly one century ago.

    Critical observations of the precise distances to galaxies in the region of MACS J1149+2223 were made using MUSE in early 2015. They have enabled astronomers to model the matter distribution inside the behemoth galaxy cluster more precisely than ever before. This has led to several predictions of when and where another image of the distant supernova — an instant replay on the biggest screen imaginable — will appear.

    Because the light that forms the multiple images of the supernova takes paths to the Earth with different lengths, they appear at different times as well as at different points on the sky.

    Using all the available MUSE data, in combination with Hubble observations, a team of astronomers led by Claudio Grillo (Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Denmark) have predicted that a further replay will peak in brightness between March and June 2016, with a possible first detection before the end of 2015. They can also anticipate not only where and when the supernova is expected to become visible again, but also approximately how bright it will appear.

    Hubble is now being periodically pointed at the cluster in hopes of catching the once-in-a-lifetime event, putting the astronomers’ models to the ultimate test in the process.

    These observations highlight the vital role that MUSE and the VLT play in the exploration of the distant Universe, as well as the synergy between Hubble and ground-based observatories.

    Notes

    [1] It is named after the late Norwegian astronomer Sjur Refsdal, who was a pioneer of the study of gravitational lenses.

    Links

    Science paper (Grillo et al)
    Related science paper (Jauzac et al)
    Related science paper (Treu et al)
    Related science paper (Karman et al)
    Related announcement from Hubble

    See the full article here .

    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 LaSilla
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