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  • richardmitnick 10:20 am on July 17, 2017 Permalink | Reply
    Tags: , , , , ESO VLT, ESO/NACO on VLT, Milky Way could have 100 billion brown dwarfs, NGC 1333, , RCW 38   

    From RAS via ESO: “Milky Way could have 100 billion brown dwarfs” 

    Royal Astronomical Society

    Royal Astronomical Society

    05 July 2017
    Media contacts
    NAM press office (Monday 3 – Thursday 6 July)
    Tel: +44 (0)1482 467507 / (0)1482 467508

    Robert Massey
    Royal Astronomical Society
    Mob: +44 (0)7802 877699
    rm@ras.org.uk

    Anita Heward
    Royal Astronomical Society
    Mob: +44 (0)7756 034243
    anitaheward@btinternet.com

    Morgan Hollis
    Royal Astronomical Society
    mh@ras.org.uk

    Science contacts

    Aleks Scholz
    University of St Andrews
    Mob: +44 (0)7399 682839

    1
    False-colour near-infrared image of the core of the young massive cluster RCW 38 taken with the adaptive-optics camera NACO at the ESO’s Very Large Telescope. RCW 38 lies at a distance of about 5500 light years from the Sun. The field of view of the central image is approximately 1 arc minute, or 1.5 light years across. The insets, each spanning about 0.07 light years on a side, show a subset of the faintest and least massive cluster candidate brown dwarfs (indicated by arrows) of RCW 38 discovered in this new image. These candidate brown dwarfs might weigh only a few tens of Jupiter masses, or about 100 times less than the most massive stars seen towards the centre of the image.

    Credit: Koraljka Muzic, University of Lisbon, Portugal / Aleks Scholz, University of St Andrews, UK / Rainer Schoedel, University of Granada, Spain / Vincent Geers, UKATC / Ray Jayawardhana, York University, Canada / Joana Ascenso, University of Lisbon, University of Porto, Portugal / Lucas Cieza, University Diego Portales, Santiago, Chile. The study is based on observations conducted with the VLT at the European Southern Observatory.

    ESO/NACO

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

    RCW 38 lies at a distance of about 5500 light years from the Sun. The field of view of the central image is approximately 1 arc minute, or 1.5 light years across. The insets, each spanning about 0.07 light years on a side, show a subset of the faintest and least massive cluster candidate brown dwarfs (indicated by arrows) of RCW 38 discovered in this new image. These candidate brown dwarfs might weigh only a few tens of Jupiter masses, or about 100 times less than the most massive stars seen towards the centre of the image. Credit: Koraljka Muzic, University of Lisbon, Portugal / Aleks Scholz, University of St Andrews, UK / Rainer Schoedel, University of Granada, Spain / Vincent Geers, UKATC / Ray Jayawardhana, York University, Canada / Joana Ascenso, University of Lisbon, University of Porto, Portugal / Lucas Cieza, University Diego Portales, Santiago, Chile. The study is based on observations conducted with the VLT at the European Southern Observatory.

    Our galaxy could have 100 billion brown dwarfs or more, according to work by an international team of astronomers, led by Koraljka Muzic from the University of Lisbon and Aleks Scholz from the University of St Andrews. On Thursday 6 July Scholz will present their survey of dense star clusters, where brown dwarfs are abundant, at the National Astronomy Meeting at the University of Hull.

    Brown dwarfs are objects intermediate in mass between stars and planets, with masses too low to sustain stable hydrogen fusion in their core, the hallmark of stars like the Sun. After the initial discovery of brown dwarfs in 1995, scientists quickly realised that they are a natural by-product of processes that primarily lead to the formation of stars and planets.

    All of the thousands of brown dwarfs found so far are relatively close to the Sun, the overwhelming majority within 1500 light years, simply because these objects are faint and therefore difficult to observe. Most of those detected are located in nearby star forming regions, which are all fairly small and have a low density of stars.

    In 2006 the team began a new search for brown dwarfs, observing five nearby star forming regions. The Substellar Objects in Nearby Young Clusters (SONYC) survey included the star cluster NGC 1333, 1000 light years away in the constellation of Perseus. That object had about half as many brown dwarfs as stars, a higher proportion than seen before.

    To establish whether NGC 1333 was unusual, in 2016 the team turned to another more distant star cluster, RCW 38, in the constellation of Vela. This has a high density of more massive stars, and very different conditions to other clusters.

    RCW 38 is 5500 light years away, meaning that the brown dwarfs are both faint, and hard to pick out next to the brighter stars. To get a clear image, Scholz, Muzic and their collaborators used the NACO adaptive optics camera on the European Southern Observatory’s Very Large Telescope, observing the cluster for a total of almost 3 hours, and combining this with earlier work.

    2
    An artist’s impression of a T-type brown dwarf. Credit: NASA / JPL-Caltech.

    The researchers found just as many brown dwarfs in RCW 38 – about half as many as there are stars- and realised that the environment where the stars form, whether stars are more or less massive, tightly packed or less crowded, has only a small effect on how brown dwarfs form.

    Scholz says: “We’ve found a lot of brown dwarfs in these clusters. And whatever the cluster type, the brown dwarfs are really common. Brown dwarfs form alongside stars in clusters, so our work suggests there are a huge number of brown dwarfs out there.”

    From the SONYC survey, Scholz and Muzic estimate that our galaxy, the Milky Way, has a minimum of between 25 and 100 billion brown dwarfs. There are many smaller, fainter brown dwarfs too, so this could be a significant underestimate, and the survey confirms these dim objects are ubiquitous.

    See the full article here .

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  • richardmitnick 10:22 am on July 5, 2017 Permalink | Reply
    Tags: , , , , ESO VLT, Messier 77   

    From ESO: “Dazzling Spiral with an Active Heart” 

    ESO 50 Large

    European Southern Observatory

    5 July 2017
    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
    ESO’s Very Large Telescope (VLT) has captured a magnificent face-on view of the barred spiral galaxy Messier 77. The image does justice to the galaxy’s beauty, showcasing its glittering arms criss-crossed with dust lanes — but it fails to betray Messier 77’s turbulent nature.

    This picturesque spiral galaxy appears to be tranquil, but there is more to it than meets the eye. Messier 77 (also known as NGC 1068) is one of the closest active galaxies, which are some of the most energetic and spectacular objects in the Universe. Their nuclei are often bright enough to outshine the whole of the rest of the galaxy. Active galaxies are among the brightest objects in the Universe and emit light at most, if not all, wavelengths, from gamma rays and X-rays all the way to microwaves and radiowaves. Messier 77 is further classified as a Type II Seyfert galaxy, characterised by being particularly bright at infrared wavelengths.

    This impressive luminosity is caused by intense radiation blasting out from a central engine — the accretion disc surrounding a supermassive black hole. Material that falls towards the black hole is compressed and heated up to incredible temperatures, causing it to radiate a tremendous amount of energy. This accretion disc is thought to be enshrouded by thick doughnut-shaped structure of gas and dust, called a “torus”. Observations of Messier 77 back in 2003 were the first to resolve such a structure using the powerful VLT Interferometer (eso0319).

    This image of Messier 77 was taken in four different wavelength bands represented by blue, red, violet and pink (hydrogen-alpha) colours. Each wavelength brings out a different quality: for example, the pinkish hydrogen-alpha highlights the hotter and younger stars forming in the spiral arms, while in red are the fine, thread-like filamentary structures in the gas surrounding Messier 77 [1]. A foreground Milky Way star is also seen beside the galaxy centre, displaying tell-tale diffraction spikes. Additionally, many more distant galaxies are visible; sitting at the outskirts of the spiral arms, they appear tiny and delicate compared to the colossal active galaxy .

    Located 47 million light-years away in the constellation of Cetus (The Sea Monster), Messier 77 is one of the most remote galaxies of the Messier catalogue. Initially, Messier believed that the highly luminous object he saw through his telescope was a cluster of stars, but as technology progressed its true status as a galaxy was realised. At approximately 100 000 light-years across, Messier 77 is also one of largest galaxies in the Messier catalogue — so massive that its gravity causes other nearby galaxies to twist and become warped (eso1707) [2].

    This image was obtained using the FOcal Reducer and low dispersion Spectrograph 2 (FORS2) instrument mounted on Unit Telescope 1 (Antu) of the VLT, located at ESO’s Paranal Observatory in Chile.

    ESO FORS2 VLT

    It hails from ESO’s Cosmic Gems programme, an outreach initiative that produces images of interesting, intriguing or visually attractive objects using ESO telescopes for the purposes of education and outreach.

    Notes

    [1] Similar red filaments are also found in NGC 1275.

    3
    This stunning image of NGC 1275 was taken using the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys in July and August 2006. It provides amazing detail and resolution of the fragile filamentary structures, which show up as a reddish lacy structure surrounding the central bright galaxy NGC 1275. These filaments are cool despite being surrounded by gas that is around 55 million degrees Celsius hot. They are suspended in a magnetic field which maintains their structure and demonstrates how energy from the central black hole is transferred to the surrounding gas.

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble ACS

    They are cool, despite being surrounded by a very hot gas at around 50 million degrees Celsius. The filaments are suspended in a magnetic field which maintains their structure and demonstrates how energy from the central black hole is transferred to the surrounding gas.

    [2] NGC 1055 is located about 60 million light-years away.

    4
    This colourful image from ESO’s Very Large Telescope shows NGC 1055 in the constellation of Cetus (The Sea Monster). This large galaxy is thought to be up to 15 percent larger in diameter than the Milky Way. NGC 1055 appears to lack the whirling arms characteristic of a spiral, as it is seen edge-on. However, it displays odd twists in its structure that were probably caused by an interaction with a large neighbouring galaxy.

    It is an edge-on galaxy, in contrast to Messier 77. This Astronomy Picture of the Day portrays both of them together, in a field of view about the size of the Moon (APOD).

    5
    Cetus Duo M77 and NGC 1055
    Image Credit & Copyright: Dieter Willasch (Astro-Cabinet)

    At the top right, large spiral galaxy NGC 1055 joins spiral Messier 77 in this sharp cosmic view toward the aquatic constellation Cetus. The narrowed, dusty appearance of edge-on spiral NGC 1055 contrasts nicely with the face-on view of Messier 77’s bright nucleus and spiral arms. Both over 100,000 light-years across, the pair are dominant members of a small galaxy group about 60 million light-years away. At that estimated distance, M77 is one of the most remote objects in Charles Messier’s catalog and is separated from fellow island universe NGC 1055 by at least 500,000 light-years. The field of view is about the size of the full Moon on the sky and includes colorful foreground Milky Way stars (with diffraction spikes) along with more distant background galaxies.

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

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

    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

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres

    ESO E-ELT
    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

    ESO APEX
    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
  • richardmitnick 9:48 am on May 21, 2017 Permalink | Reply
    Tags: , , , , , ESO VLT,   

    From Manu Garcia: “M83, Messier 83, a barred spiral galaxy” 


    Manu Garcia, a friend from IAC.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    1
    The galaxy Messier 83 is located about 15 million away in the constellation Hydra light-years. Its extension reaches more than 40 thousand light-years, only 40 percent of the size of the Milky Way, but in many ways is similar to our home galaxy, both in its spiral shape and the presence of a band of stars that crosses its center. Messier 83 is famous among astronomers for its many supernovae: vast explosions that killed some stars. In the past century , six supernovae were observed in Messier 83 , a record number has been reached only by a galaxy. Even without supernovae, Messier 83 is one of the brightest nearby galaxies that can be seen using binoculars.

    ESO unveiled one of the most accurate and detailed portraits obtained so far from the nearby galaxy Messier 83. The image, taken with the instrument HAWK-I’s Very Large Telescope (VLT) at the Paranal Observatory (Chile) , shows the galaxy in infrared light and demonstrates the incredible power of this camera.

    ESO HAWK-I

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

    The combination of the huge mirror of the VLT , the large field of view and sensitivity of the camera, and the superb observing conditions of Paranal Observatory ESO , makes HAWK-I one of the most powerful cameras in the world in near infrared. Astronomers eagerly await their turn to use this camera, which began operations in 2007, and to obtain some of the best infrared images taken from Earth to the night sky.

    notes
    [1] HAWK-I stands for High-Acuity Wide-field K-band Imager or high acuity camera, wide – field band K.

    [2] The data used to prepare this were assembled by a team led by Mark Gieles (Cambridge University) and Yuri Beletsky (ESO). Mirna Schirmer (University of Bonn) performed the complex data processing.

    See the full article here .

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  • richardmitnick 10:24 am on March 27, 2017 Permalink | Reply
    Tags: , , , , , ESO VLT, ESO X-shooter, IRAS F23128-5919, Stars Born in Winds from Supermassive Black Holes   

    From ESO: “Stars Born in Winds from Supermassive Black Holes” 

    ESO 50 Large

    European Southern Observatory

    27 March 2017
    Roberto Maiolino
    Cavendish Laboratory, Kavli Institute for Cosmology
    University of Cambridge, UK
    Email: r.maiolino@mrao.cam.ac.uk

    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
    Observations using ESO’s Very Large Telescope have revealed stars forming within powerful outflows of material blasted out from supermassive black holes at the cores of galaxies. These are the first confirmed observations of stars forming in this kind of extreme environment. The discovery has many consequences for understanding galaxy properties and evolution. The results are published in the journal Nature.

    A UK-led group of European astronomers used the MUSE and X-shooter instruments on the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile to study an ongoing collision between two galaxies, known collectively as IRAS F23128-5919, that lie around 600 million light-years from Earth. The group observed the colossal winds of material — or outflows — that originate near the supermassive black hole at the heart of the pair’s southern galaxy, and have found the first clear evidence that stars are being born within them [1].

    2
    IRAS F23128-5919 https://inspirehep.net/record/1265769/plots


    ESO/MUSE on VLT


    ESO X-shooter on VLT

    Such galactic outflows are driven by the huge energy output from the active and turbulent centres of galaxies. Supermassive black holes lurk in the cores of most galaxies, and when they gobble up matter they also heat the surrounding gas and expel it from the host galaxy in powerful, dense winds [2].

    “Astronomers have thought for a while that conditions within these outflows could be right for star formation, but no one has seen it actually happening as it’s a very difficult observation,” comments team leader Roberto Maiolino from the University of Cambridge. “Our results are exciting because they show unambiguously that stars are being created inside these outflows.”

    The group set out to study stars in the outflow directly, as well as the gas that surrounds them. By using two of the world-leading VLT spectroscopic instruments, MUSE and X-shooter, they could carry out a very detailed study of the properties of the emitted light to determine its source.

    Radiation from young stars is known to cause nearby gas clouds to glow in a particular way. The extreme sensitivity of X-shooter allowed the team to rule out other possible causes of this illumination, including gas shocks or the active nucleus of the galaxy.

    The group then made an unmistakable direct detection of an infant stellar population in the outflow [3]. These stars are thought to be less than a few tens of millions of years old, and preliminary analysis suggests that they are hotter and brighter than stars formed in less extreme environments such as the galactic disc.

    As further evidence, the astronomers also determined the motion and velocity of these stars. The light from most of the region’s stars indicates that they are travelling at very large velocities away from the galaxy centre — as would make sense for objects caught in a stream of fast-moving material.

    Co-author Helen Russell (Institute of Astronomy, Cambridge, UK) expands: “The stars that form in the wind close to the galaxy centre might slow down and even start heading back inwards, but the stars that form further out in the flow experience less deceleration and can even fly off out of the galaxy altogether.”

    The discovery provides new and exciting information that could better our understanding of some astrophysics, including how certain galaxies obtain their shapes [4]; how intergalactic space becomes enriched with heavy elements [5]; and even from where unexplained cosmic infrared background radiation may arise [6].

    Maiolino is excited for the future: “If star formation is really occurring in most galactic outflows, as some theories predict, then this would provide a completely new scenario for our understanding of galaxy evolution.”
    Notes

    [1] Stars are forming in the outflows at a very rapid rate; the astronomers say that stars totalling around 30 times the mass of the Sun are being created every year. This accounts for over a quarter of the total star formation in the entire merging galaxy system.

    [2] The expulsion of gas through galactic outflows leads to a gas-poor environment within the galaxy, which could be why some galaxies cease forming new stars as they age. Although these outflows are most likely to be driven by massive central black holes, it is also possible that the winds are powered by supernovae in a starburst nucleus undergoing vigorous star formation.

    [3] This was achieved through the detection of signatures characteristic of young stellar populations and with a velocity pattern consistent with that expected from stars formed at high velocity in the outflow.

    [4] Spiral galaxies have an obvious disc structure, with a distended bulge of stars in the centre and surrounded by a diffuse cloud of stars called a halo. Elliptical galaxies are composed mostly of these spheroidal components. Outflow stars that are ejected from the main disc could give rise to these galactic features.

    [5] How the space between galaxies — the intergalactic medium — becomes enriched with heavy elements is still an open issue, but outflow stars could provide an answer. If they are jettisoned out of the galaxy and then explode as supernovae, the heavy elements they contain could be released into this medium.

    [6] Cosmic-infrared background radiation, similar to the more famous cosmic microwave background, is a faint glow in the infrared part of the spectrum that appears to come from all directions in space. Its origin in the near-infrared bands, however, has never been satisfactorily ascertained. A population of outflow stars shot out into intergalactic space may contribute to this light.
    More information

    This research was presented in a paper entitled “Star formation in a galactic outflow” by Maiolino et al., to appear in the journal Nature on 27 March 2017 [link is above with image detail].

    The team is composed of R. Maiolino (Cavendish Laboratory; Kavli Institute for Cosmology, University of Cambridge, UK), H.R. Russell (Institute of Astronomy, Cambridge, UK), A.C. Fabian (Institute of Astronomy, Cambridge, UK), S. Carniani (Cavendish Laboratory; Kavli Institute for Cosmology, University of Cambridge, UK), R. Gallagher (Cavendish Laboratory; Kavli Institute for Cosmology, University of Cambridge, UK), S. Cazzoli (Departamento de Astrofisica-Centro de Astrobiología, Madrid, Spain), S. Arribas (Departamento de Astrofisica-Centro de Astrobiología, Madrid, Spain), F. Belfiore ((Cavendish Laboratory; Kavli Institute for Cosmology, University of Cambridge, UK), E. Bellocchi (Departamento de Astrofisica-Centro de Astrobiología, Madrid, Spain), L. Colina (Departamento de Astrofisica-Centro de Astrobiología, Madrid, Spain), G. Cresci (Osservatorio Astrofisico di Arcetri, Firenze, Italy), W. Ishibashi (Universität Zürich, Zürich, Switzerland), A. Marconi (Osservatorio Astrofisico di Arcetri, Firenze, Italy), F. Mannucci (Osservatorio Astrofisico di Arcetri, Firenze, Italy), E. Oliva (Osservatorio Astrofisico di Arcetri, Firenze, Italy), and E. Sturm (Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany).

    See the full article here .

    Please help promote STEM in your local schools.
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    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 European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

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

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

    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

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres

    ESO E-ELT
    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

    ESO APEX
    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
  • richardmitnick 1:44 pm on March 15, 2017 Permalink | Reply
    Tags: , , , , Dark Matter Less Influential in Galaxies in Early Universe, ESO KMOS, ESO SINFONI, ESO VLT   

    From ESO: “Dark Matter Less Influential in Galaxies in Early Universe” 

    ESO 50 Large

    European Southern Observatory

    15 March 2017
    Reinhard Genzel
    Director, Max-Planck-Institut für extraterrestrische Physik
    Garching bei München, Germany
    Tel: +49 89 30000 3280
    Email: genzel@mpe.mpg.de

    Natascha M. Forster Schreiber
    Senior Scientist, Max-Planck-Institut für extraterrestrische Physik
    Garching bei München, Germany
    Tel: +49 89 30000 3524
    Email: forster@mpe.mpg.de

    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
    Schematic representation of rotating disc galaxies in the early Universe (right) and the present day (left). Observations with ESO’s Very Large Telescope suggest that such massive star-forming disc galaxies in the early Universe were less influenced by dark matter (shown in red), as it was less concentrated. As a result the outer parts of distant galaxies rotate more slowly than comparable regions of galaxies in the local Universe. Credit: ESO/L. Calçada

    2
    Schematic representation of rotating disc galaxies in the distant Universe and the present day. Observations with ESO’s Very Large Telescope suggest that such massive star-forming disc galaxies in the early Universe were less influenced by dark matter. As a result the outer parts of distant galaxies rotate more slowly than comparable regions of galaxies in the local Universe. Their rotations curves, rather than being flat, drop with increasing radius. Credit: ESO


    Access mp4 video here .
    New observations from ESO’s Very Large Telescope have revealed that the outer parts of massive disc galaxies 10 billion years ago were rotating less quickly than the spiral galaxies, like the Milky Way, that we see today. This ESOcast Light summarises the important points of this discovery and the significance of dark matter, and how it is distributed.
    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

    Editing: Herbert Zodet.
    Web and technical support: Mathias André and Raquel Yumi Shida.
    Written by: Thomas Barratt and Lauren Fuge.
    Music: Jennifer Athena Galatis.
    Footage and photos: ESO, The Illustris Project (visualization by Dylan Nelson), L. Calçada and F. Char.
    Directed by: Herbert Zodet.
    Executive producer: Lars Lindberg Christensen.

    New observations indicate that massive, star-forming galaxies during the peak epoch of galaxy formation, 10 billion years ago, were dominated by baryonic or “normal” matter. This is in stark contrast to present-day galaxies, where the effects of mysterious dark matter seem to be much greater. This surprising result was obtained using ESO’s Very Large Telescope and suggests that dark matter was less influential in the early Universe than it is today. The research is presented in four papers, one of which was published in the journal Nature today.

    We see normal matter as brightly shining stars, glowing gas and clouds of dust. But the more elusive dark matter does not emit, absorb or reflect light and can only be observed via its gravitational effects. The presence of dark matter can explain why the outer parts of nearby spiral galaxies rotate more quickly than would be expected if only the normal matter that we can see directly were present [1].

    Now, an international team of astronomers led by Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany have used the KMOS and SINFONI instruments at ESO’s Very Large Telescope in Chile [2] to measure the rotation of six massive, star-forming galaxies in the distant Universe, at the peak of galaxy formation 10 billion years ago.


    KMOS


    SINFONI

    What they found was intriguing: unlike spiral galaxies in the modern Universe, the outer regions of these distant galaxies seem to be rotating more slowly than regions closer to the core — suggesting there is less dark matter present than expected [3].

    “Surprisingly, the rotation velocities are not constant, but decrease further out in the galaxies,” comments Reinhard Genzel, lead author of the Nature paper. “There are probably two causes for this. Firstly, most of these early massive galaxies are strongly dominated by normal matter, with dark matter playing a much smaller role than in the Local Universe. Secondly, these early discs were much more turbulent than the spiral galaxies we see in our cosmic neighbourhood.”

    Both effects seem to become more marked as astronomers look further and further back in time, into the early Universe. This suggests that 3 to 4 billion years after the Big Bang, the gas in galaxies had already efficiently condensed into flat, rotating discs, while the dark matter halos surrounding them were much larger and more spread out. Apparently it took billions of years longer for dark matter to condense as well, so its dominating effect is only seen on the rotation velocities of galaxy discs today

    This explanation is consistent with observations showing that early galaxies were much more gas-rich and compact than today’s galaxies.

    The six galaxies mapped in this study were among a larger sample of a hundred distant, star-forming discs imaged with the KMOS and SINFONI instruments at ESO’s Very Large Telescope at the Paranal Observatory in Chile. In addition to the individual galaxy measurements described above, an average rotation curve was created by combining the weaker signals from the other galaxies. This composite curve also showed the same decreasing velocity trend away from the centres of the galaxies. In addition, two further studies of 240 star forming discs also support these findings.

    Detailed modelling shows that while normal matter typically accounts for about half of the total mass of all galaxies on average, it completely dominates the dynamics of galaxies at the highest redshifts.
    Notes

    [1] The disc of a spiral galaxy rotates over a timescale of hundreds of millions of years. Spiral galaxy cores have high concentrations of stars, but the density of bright matter decreases towards their outskirts. If a galaxy’s mass consisted entirely of normal matter, then the sparser outer regions should rotate more slowly than the dense regions at the centre. But observations of nearby spiral galaxies show that their inner and outer parts actually rotate at approximately the same speed. These “flat rotation curves ” indicate that spiral galaxies must contain large amounts of non-luminous matter in a dark matter halo surrounding the galactic disc.

    [2] The data analysed were obtained with the integral field spectrometers KMOS and SINFONI at ESO’s Very Large Telescope in Chile in the framework of the KMOS3D and SINS/zC-SINF surveys. It is the first time that such a comprehensive study of the dynamics of a large number of galaxies spanning the redshift interval from z~0.6 to 2.6, or 5 billion years of cosmic time, has been carried out.

    [3] This new result does not call into question the need for dark matter as a fundamental component of the Universe or the total amount. Rather it suggests that dark matter was differently distributed in and around disc galaxies at early times compared to the present day.
    More information

    This research was presented in a paper entitled Strongly baryon dominated disk galaxies at the peak of galaxy formation ten billion years ago, by R. Genzel et al., to appear in the journal Nature.

    The team is composed of R. Genzel (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; University of California, Berkeley, USA), N.M. Förster Schreiber (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), H. Übler (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), P. Lang (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), T. Naab (Max-Planck-Institut für Astrophysik, Garching, Germany), R. Bender (Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany; Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), L.J. Tacconi (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), E. Wisnioski (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), S.Wuyts (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; University of Bath, Bath, UK), T. Alexander (The Weizmann Institute of Science, Rehovot, Israel), A. Beifiori (Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany; Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), S.Belli (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), G. Brammer (Space Telescope Science Institute, Baltimore, USA), A.Burkert (Max-Planck-Institut für Astrophysik, Garching, Germany; Max-Planck-Institut für extraterrestrische Physik, Garching, Germany) C.M. Carollo (Eidgenössische Technische Hochschule, Zürich, Switzerland), J. Chan (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), R. Davies (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), M. Fossati (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany), A. Galametz (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany), S. Genel (Center for Computational Astrophysics, New York, USA), O. Gerhard (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), D. Lutz (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany), J.T. Mendel (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany), I. Momcheva (Yale University, New Haven, USA), E.J. Nelson (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; Yale University, New Haven, USA), A. Renzini (Vicolo dell’Osservatorio 5, Padova, Italy), R.Saglia (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany), A. Sternberg (Tel Aviv University, Tel Aviv, Israel), S. Tacchella (Eidgenössische Technische Hochschule, Zürich, Switzerland), K.Tadaki (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany) and D. Wilman (Universitäts-Sternwarte Ludwig-Maximilians-Universität, München, Germany; Max-Planck-Institut für extraterrestrische Physik, Garching, Germany)

    Links

    Research Paper 1
    Research Paper 2
    Research Paper 3
    Research Paper 4

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

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

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

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

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

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    ALMA on the Chajnantor plateau at 5,000 metres

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    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

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    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
    • gregoriobaquero 7:26 pm on March 15, 2017 Permalink | Reply

      The younger the galaxy (the farther away we look) the less DM. It is an accumulative phenomenon.

      Like

  • richardmitnick 8:08 am on March 8, 2017 Permalink | Reply
    Tags: A2744_YD4, , Ancient Stardust Sheds Light on the First Stars, , , ESO VLT   

    From ALMA: “Ancient Stardust Sheds Light on the First Stars” 

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

    3.8.17

    Nicolas Laporte
    University College London
    United Kingdom
    Tel: +44 2 035 495 802
    Cell: +44 7452 807 591
    Email: n.laporte@ucl.ac.uk

    Richard Ellis
    ESO Garching bei München, Germany
    Tel: +44 7885 403334
    Cell: +49 151 629 56829
    Email: rellis@eso.org

    Nicolás Lira T.
    Press Coordinator
    Joint ALMA Observatory
    Santiago, Chile
    Tel: +56 2 24 67 65 19
    Cell: +56 9 94 45 77 26
    Email: nicolas.lira@alma.cl

    Richard Hook
    Public Information Officer, ESO

    Garching bei München, Germany

    Tel: +49 89 3200 6655

    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Masaaki Hiramatsu

    Education and Public Outreach Officer, NAOJ Chile
    Observatory
Tokyo, Japan

    Tel: +81 422 34 3630

    E-mail: hiramatsu.masaaki@nao.ac.jp

    Charles E. Blue
    Public Information Officer
    National Radio Astronomy Observatory
    Charlottesville, Virginia, USA
    Tel: +1 434 296 0314
    Cell: +1 202 236 6324
    E-mail: cblue@nrao.edu

    1
    Astronomers have used ALMA to detect a huge mass of glowing stardust in a galaxy seen when the Universe was only four percent of its present age. This galaxy was observed shortly after its formation and is the most distant galaxy in which dust has been detected. This observation is also the most distant detection of oxygen in the Universe. These new results provide brand-new insights into the birth and explosive deaths of the very first stars.

    3
    ALMA and Hubble Space Telescope views of the distant dusty galaxy A2744_YD4. This image is dominated by a spectacular view of the rich galaxy cluster Abell 2744 from the NASA/ESA Hubble Space Telescope. But, far beyond this cluster, and seen when the Universe was only about 600 million years old, is a very faint galaxy called A2744_YD4. New observations of this galaxy with ALMA, shown in red, have demonstrated that it is rich in dust. Credit: ALMA (ESO/NAOJ/NRAO), NASA, ESA, ESO and D. Coe (STScI)/J. Merten (Heidelberg/Bologna)

    An international team of astronomers, led by Nicolas Laporte of University College London, have used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe A2744_YD4, the youngest and most remote galaxy ever seen by ALMA. They were surprised to find that this youthful galaxy contained an abundance of interstellar dust — dust formed by the deaths of an earlier generation of stars.

    Follow-up observations using the X-shooter instrument on ESO’s Very Large Telescope confirmed the enormous distance to A2744_YD4. The galaxy appears to us as it was when the Universe was only 600 million years old, during the period when the first stars and galaxies were forming [1].

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

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

    “Not only is A2744_YD4 the most distant galaxy yet observed by ALMA,” comments Nicolas Laporte, “but the detection of so much dust indicates early supernovae must have already polluted this galaxy.”

    Cosmic dust is mainly composed of silicon, carbon and aluminium, in grains as small as a millionth of a centimetre across. The chemical elements in these grains are forged inside stars and are scattered across the cosmos when the stars die, most spectacularly in supernova explosions, the final fate of short-lived, massive stars. Today, this dust is plentiful and is a key building block in the formation of stars, planets and complex molecules; but in the early Universe — before the first generations of stars died out — it was scarce.

    The observations of the dusty galaxy A2744_YD4 were made possible because this galaxy lies behind a massive galaxy cluster called Abell 2744 [2].

    1
    Abell 2744, nicknamed Pandora’s Cluster. The galaxies in the cluster make up less than five percent of its mass. The gas (around 20 percent) is so hot that it shines only in X-rays (coloured red in this image). The distribution of invisible dark matter (making up around 75 percent of the cluster’s mass) is coloured here in blue.
    Date 22 June 2011
    Source HubbleSite
    Author NASA, ESA, J. Merten (Institute for Theoretical Astrophysics, Heidelberg/Astronomical Observatory of Bologna), and D. Coe (STScI)

    Because of a phenomenon called gravitational lensing, the cluster acted like a giant cosmic “telescope” to magnify the more distant A2744_YD4 by about 1.8 times, allowing the team to peer far back into the early Universe.

    Gravitational Lensing NASA/ESA
    Gravitational Lensing NASA/ESA

    Gravitational microlensing, S. Liebes, Physical Review B, 133 (1964): 835
    Gravitational microlensing, S. Liebes, Physical Review B, 133 (1964)

    The ALMA observations also detected the glowing emission of ionised oxygen from A2744_YD4. This is the most distant, and hence earliest, detection of oxygen in the Universe, surpassing another ALMA result from 2016.

    The detection of dust in the early Universe provides new information on when the first supernovae exploded and hence the time when the first hot stars bathed the Universe in light. Determining the timing of this “cosmic dawn” is one of the holy grails of modern astronomy, and it can be indirectly probed through the study of early interstellar dust.

    The team estimates that A2744_YD4 contained an amount of dust equivalent to 6 million times the mass of our Sun, while the galaxy’s total stellar mass — the mass of all its stars — was 2 billion times the mass of our Sun. The team also measured the rate of star formation in A2744_YD4 and found that stars are forming at a rate of 20 solar masses per year — compared to just one solar mass per year in the Milky Way [3].

    “This rate is not unusual for such a distant galaxy, but it does shed light on how quickly the dust in A2744_YD4 formed,” explains Richard Ellis (ESO and University College London), a co-author of the study. “Remarkably, the required time is only about 200 million years — so we are witnessing this galaxy shortly after its formation.”

    This means that significant star formation began approximately 200 million years before the epoch at which the galaxy is being observed. This provides a great opportunity for ALMA to help study the era when the first stars and galaxies “switched on” — the earliest epoch yet probed. Our Sun, our planet and our existence are the products — 13 billion years later — of this first generation of stars. By studying their formation, lives and deaths, we are exploring our origins.

    “With ALMA, the prospects for performing deeper and more extensive observations of similar galaxies at these early times are very promising,” says Ellis.

    And Laporte concludes: “Further measurements of this kind offer the exciting prospect of tracing early star formation and the creation of the heavier chemical elements even further back into the early Universe.”
    Notes

    [1] This time corresponds to a redshift of z=8.38, during the epoch of reionisation.

    [2] Abell 2744 is a massive object, lying 3.5 billion light-years away (redshift 0.308), that is thought to be the result of four smaller galaxy clusters colliding. It has been nicknamed Pandora’s Cluster because of the many strange and different phenomena that were unleashed by the huge collision that occurred over a period of about 350 million years. The galaxies only make up five percent of the cluster’s mass, while dark matter makes up seventy-five percent, providing the massive gravitational influence necessary to bend and magnify the light of background galaxies. The remaining twenty percent of the total mass is thought to be in the form of hot gas.

    [3] This rate means that the total mass of the stars formed every year is equivalent to 20 times the mass of the Sun.
    More information

    This research was presented in a paper entitled Dust in the Reionization Era: ALMA Observations of a z =8.38 Gravitationally-Lensed Galaxy by Laporte et al., to appear in The Astrophysical Journal Letters.

    The team is composed of N. Laporte (University College London, UK), R. S. Ellis (University College London, UK; ESO, Garching, Germany), F. Boone (Institut de Recherche en Astrophysique et Planétologie (IRAP), Toulouse, France), F. E. Bauer (Pontificia Universidad Católica de Chile, Instituto de Astrofísica, Santiago, Chile), D. Quénard (Queen Mary University of London, London, UK), G. Roberts-Borsani (University College London, UK), R. Pelló (Institut de Recherche en Astrophysique et Planétologie (IRAP), Toulouse, France), I. Pérez-Fournon (Instituto de Astrofísica de Canarias, Tenerife, Spain; Universidad de La Laguna, Tenerife, Spain), and A. Streblyanska (Instituto de Astrofísica de Canarias, Tenerife, Spain; Universidad de La Laguna, Tenerife, Spain).

    See the full article here .

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    The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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  • richardmitnick 9:16 am on March 1, 2017 Permalink | Reply
    Tags: A Galaxy on the Edge, , , , , ESO VLT   

    From ESO: “A Galaxy on the Edge” 

    ESO 50 Large

    European Southern Observatory

    1 March 2017
    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
    This colourful stripe of stars, gas, and dust is actually a spiral galaxy named NGC 1055. Captured here by ESO’s Very Large Telescope (VLT), this big galaxy is thought to be up to 15 percent larger in diameter than the Milky Way. NGC 1055 appears to lack the whirling arms characteristic of a spiral, as it is seen edge-on. However, it displays odd twists in its structure that were probably caused by an interaction with a large neighbouring galaxy.

    Spiral galaxies throughout the Universe take on all manner of orientations with respect to Earth. We see some from above (as it were) or “face-on” — a good example of this being the whirlpool-shaped galaxy NGC 1232.

    2
    The striking, large spiral galaxy NGC 1232, and its distorted companion shaped like the greek letter “theta”. The pair is located roughly 70 million light years away in the constellation Eridanus (The River). Billions of stars and dark dust are caught up in this beautiful gravitational swirl. The blue spiral arms with their many young stars and star-forming regions make a striking contrast with the yellow-reddish core of older stars. This image is based on data acquired with the 1.5 m Danish telescope at the ESO La Silla Observatory in Chile, through three filters (B: 900 s, V: 400 s, R: 400 s). East is up, North is to the right. Credit: ESO/IDA/Danish 1.5 m/R.Gendler and A. Hornstrup. ID: NGC1232B. Credit: ESO

    Such orientations reveal a galaxy’s flowing arms and bright core in beautiful detail, but make it difficult to get any sense of a three-dimensional shape.

    We see other galaxies, such as NGC 3521, at angles.

    3
    NGC 3521. HST

    While these tilted objects begin to reveal the three-dimensional structure within their spiral arms, fully understanding the overall shape of a spiral galaxy requires an edge-on view — such as this one of NGC 1055.

    4
    NGC 1055. http://irsa.ipac.caltech.edu/cgi-bin/2MASS/LGA/nph-lga?objstr=ngc1055; http://ned.ipac.caltech.edu/cgi-bin/imgdata?objname=NGC+1055

    When seen edge-on, it is possible to get an overall view of how stars — both new patches of starbirth and older populations — are distributed throughout a galaxy, and the “heights” of the relatively flat disc and the star-loaded core become easier to measure. Material stretches away from the blinding brightness of the galactic plane itself, becoming more clearly observable against the darker background of the cosmos.

    Such a perspective also allows astronomers to study the overall shape of a galaxy’s extended disc, and to study its properties. One example of this is warping, which is something we see in NGC 1055. The galaxy has regions of peculiar twisting and disarray in its disc, likely caused by interactions with the nearby galaxy Messier 77 (eso0319) [1]. This warping is visible here; NGC 1055’s disc is slightly bent and appears to wave across the core.

    NGC 1055 is located approximately 55 million light-years away in the constellation of Cetus (The Sea Monster). This image was obtained using the FOcal Reducer and low dispersion Spectrograph 2 (FORS2) instrument mounted on Unit Telescope 1 (Antu) of the VLT, located at ESO’s Paranal Observatory in Chile.

    ESO FORS2 VLT
    ESO FORS2 VLT

    It hails from ESO’s Cosmic Gems programme, an outreach initiative that produces images of interesting, intriguing or visually attractive objects using ESO telescopes for the purposes of education and outreach.

    Notes

    [1] Messier 77, also known as NGC 1068, has a very brilliant central region powered by a supermassive black hole. It is one of the nearest examples of what astronomers call active galaxies.

    5
    Hubble Space Telescope image of Messier 77 spiral galaxy. A version of this image won second place in the Hubble’s Hidden Treasures Image Processing Competition.
    Date 28 March 2013
    Source http://www.spacetelescope.org/news/heic1305/
    Author NASA, ESA & A. van der Hoeven

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

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

    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

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    ALMA on the Chajnantor plateau at 5,000 metres

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    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

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    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
  • richardmitnick 6:23 am on February 1, 2017 Permalink | Reply
    Tags: , , , Celestial Cat Meets Cosmic Lobster, , ESO Omegacam, ESO VLT, , , NGC 6334 and NGC 6357   

    From ESO: “Celestial Cat Meets Cosmic Lobster” 

    ESO 50 Large

    European Southern Observatory

    1 February 2017
    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 for a long time studied the glowing, cosmic clouds of gas and dust catalogued as NGC 6334 and NGC 6357, this gigantic new image from ESO’s Very Large Telescope Survey Telescope being only the most recent one. With around two billion pixels this is one of the largest images ever released by ESO. The evocative shapes of the clouds have led to their memorable names: the Cat’s Paw Nebula and the Lobster Nebula, respectively.

    2
    This montage shows a few of the highlights from a spectacular image from the VLT Survey Telescope showing the Cat’s Paw Nebula (NGC 6334) and the Lobster Nebula (NGC 6357). This part of the sky contains active regions of star formation where hot young stars make their surrounding clouds of hydrogen glow with a characteristic red colour. There are also clouds of dark dust in this rich celestial landscape. Credit: ESO

    NGC 6334 is located about 5500 light-years away from Earth, while NGC 6357 is more remote, at a distance of 8000 light-years. Both are in the constellation of Scorpius (The Scorpion), near the tip of its stinging tail.

    The British scientist John Herschel first saw traces of the two objects, on consecutive nights in June 1837, during his three-year expedition to the Cape of Good Hope in South Africa. At the time, the limited telescopic power available to Herschel, who was observing visually, only allowed him to document the brightest “toepad” of the Cat’s Paw Nebula. It was to be many decades before the true shapes of the nebulae became apparent in photographs — and their popular names coined.

    The three toepads visible to modern telescopes, as well as the claw-like regions in the nearby Lobster Nebula, are actually regions of gas — predominantly hydrogen — energised by the light of brilliant newborn stars. With masses around 10 times that of the Sun, these hot stars radiate intense ultraviolet light. When this light encounters hydrogen atoms still lingering in the stellar nursery that produced the stars, the atoms become ionised. Accordingly, the vast, cloud-like objects that glow with this light from hydrogen (and other) atoms are known as emission nebulae.

    Thanks to the power of the 256-megapixel OmegaCAM camera, this new Very Large Telescope Survey Telescope (VST) image reveals tendrils of light-obscuring dust rippling throughout the two nebulae.

    ESO Omegacam on VST at ESO's Cerro Paranal observatory

    At 49511 x 39136 pixels this is one of the largest images ever released by ESO.

    OmegaCAM is a successor to ESO’s celebrated Wide Field Imager (WFI), currently installed at the MPG/ESO 2.2-metre telescope on La Silla.

    ESO Wide Field Imager 2.2m LaSilla
    ESO Wide Field Imager 2.2m LaSilla

    The WFI was used to photograph the Cat’s Paw Nebula in 2010, also in visible light but with a filter that allowed the glow of hydrogen to shine through more clearly (eso1003). Meanwhile, ESO’s Very Large Telescope has taken a deep look into the Lobster Nebula, capturing the many hot, bright stars that influence the object’s colour and shape (eso1226).

    Despite the cutting-edge instruments used to observe these phenomena, the dust in these nebulae is so thick that much of their content remains hidden to us. The Cat’s Paw Nebula is one of the most active stellar nurseries in the night sky, nurturing thousands of young, hot stars whose visible light is unable to reach us. However, by observing at infrared wavelengths, telescopes such as ESO’s VISTA can peer through the dust and reveal the star formation activity within.

    Viewing nebulae in different wavelengths (colours) of light gives rise to different visual comparisons on the part of human observers. When seen in longer wavelength infrared light, for example, one portion of NGC 6357 resembles a dove, and the other a skull; it has therefore acquired the additional name of the War and Peace Nebula.


    Access mp4 video here .
    A new image from ESO’s VLT Survey Telescope gives a very detailed view of the star formation regions NGC 6334 and NGC 6357, often called the Cat’s Paw Nebula and the Lobster Nebula, respectively, because of their distinctive shapes. This ESOcast Light takes a quick look at this spectacular vista and explains what it shows.


    Access mp4 video here .
    This video sequence takes a close look at a spectacular image from the VLT Survey Telescope. It shows the Cat’s Paw Nebula (NGC 6334) and the Lobster Nebula (NGC 6357). These are regions of active star formation where the hot young stars are causing the surrounding hydrogen gas to glow red. The very rich field of view also includes dark clouds of dust. Credit: ESO/N. Bartmann. Music credit: Johan B. Monell

    You can subscribe to the ESOcast in iTunes, receive future episodes on YouTube or follow us on Vimeo.

    Many other ESOcast episodes are also available on our website.

    Find out how to view and contribute subtitles to the ESOcast in multiple languages, or translate this video on dotSUB.

    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.

    Visual Design and Editing: Martin Kornmesser and Luis Calçada.
    Editing: Herbert Zodet.
    Web and technical support: Mathias André and Raquel Yumi Shida.
    Written by: Oana Sandu and Lars Lindberg Christensen.
    Music: STAN DART (http://www.stan-dart.com)
    Footage and photos: ESO, N. Risinger (skysurvey.org) and Y. Beletsky (LCO).
    Directed by: Herbert Zodet.
    Executive producer: Lars Lindberg Christensen.

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

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

    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

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres

    ESO E-ELT
    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

    ESO APEX
    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
  • richardmitnick 3:13 pm on January 9, 2017 Permalink | Reply
    Tags: , , ESO VLT, VLT to Search for Planets in Alpha Centauri System   

    From ESO: “VLT to Search for Planets in Alpha Centauri System” 

    ESO 50 Large

    European Southern Observatory

    9 January 2017
    Markus Kasper
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6359
    Email: mkasper@eso.org

    Breakthrough Initiatives
    Email: media@breakthroughprize.org

    Janet Wootten
    Rubenstein Communications, Inc.
    Tel: +1 212 843 8024
    Email: jwootten@rubenstein.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

    ESO Signs Agreement with Breakthrough Initiatives

    1
    ESO has signed an agreement with the Breakthrough Initiatives to adapt the Very Large Telescope instrumentation in Chile to conduct a search for planets in the nearby star system Alpha Centauri. Such planets could be the targets for an eventual launch of miniature space probes by the Breakthrough Starshot initiative. No image credit.

    ESO, represented by the Director General, Tim de Zeeuw, has signed an agreement with the Breakthrough Initiatives, represented by Pete Worden, Chairman of the Breakthrough Prize Foundation and Executive Director of the Breakthrough Initiatives. The agreement provides funds for the VISIR (VLT Imager and Spectrometer for mid-Infrared) instrument, mounted at ESO’s Very Large Telescope (VLT) to be modified in order to greatly enhance its ability to search for potentially habitable planets around Alpha Centauri, the closest stellar system to the Earth. The agreement also provides for telescope time to allow a careful search programme to be conducted in 2019.

    The discovery in 2016 of a planet, Proxima b, around Proxima Centauri, the third and faintest star of the Alpha Centauri system, adds even further impetus to this search.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker
    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    Knowing where the nearest exoplanets are is of paramount interest for Breakthrough Starshot, the research and engineering programme launched in April 2016, which aims to demonstrate proof of concept for ultra-fast light-driven “nanocraft”, laying the foundation for the first launch to Alpha Centauri within a generation.

    Detecting a habitable planet is an enormous challenge due to the brightness of the planetary system’s host star, which tends to overwhelm the relatively dim planets. One way to make this easier is to observe in the mid-infrared wavelength range, where the thermal glow from an orbiting planet greatly reduces the brightness gap between it and its host star. But even in the mid-infrared, the star remains millions of times brighter than the planets to be detected, which calls for a dedicated technique to reduce the blinding stellar light.

    The existing mid-infrared instrument VISIR on the VLT will provide such performance if it were enhanced to greatly improve the image quality using adaptive optics, and adapted to employ a technique called coronagraphy to reduce the stellar light and thereby reveal the possible signal of potential terrestrial planets. Breakthrough Initiatives will pay for a large fraction of the necessary technologies and development costs for such an experiment, and ESO will provide the required observing capabilities and time.

    The new hardware includes an instrument module contracted to Kampf Telescope Optics (KTO), Munich, which will host the wavefront sensor, and a novel detector calibration device. In addition, there are plans for a new coronagraph to be developed jointly by University of Liège (Belgium) and Uppsala University (Sweden).

    Detecting and studying potentially habitable planets orbiting other stars will be one of the main scientific goals of the upcoming European Extremely Large Telescope (E-ELT).

    Although the increased size of the E-ELT will be essential to obtaining an image of a planet at larger distances in the Milky Way, the light collecting power of the VLT is just sufficient to image a planet around the nearest star, Alpha Centauri.

    The developments for VISIR will also be beneficial for the future METIS instrument, to be mounted on the E-ELT, as the knowledge gained and proof of concept will be directly transferable. The huge size of the E-ELT should allow METIS to detect and study exoplanets the size of Mars orbiting Alpha Centauri, if they exist, as well as other potentially habitable planets around other nearby stars.
    More information

    The Breakthrough Initiatives are a program of scientific and technological exploration founded in 2015 by Internet investor and science philanthropist Yuri Milner to explore the Universe, seek scientific evidence of life beyond Earth, and encourage public debate from a planetary perspective.

    Breakthrough Starshot is a $100 million research and engineering program aiming to demonstrate proof of concept for a new technology, enabling ultra-light unmanned space flight at 20% of the speed of light, and to lay the foundations for a flyby mission to Alpha Centauri within a generation.

    Breakthrough Initiative

    See the full article here .

    Also on this project,

    gbo-logo
    GBO radio telescope, Green Bank, West Virginia, USA
    GBO radio telescope, Green Bank, West Virginia, USA

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia
    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    UC Observatories Lick Aumated Planet Finder, fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA
    UC Observatories Lick Aumated Planet Finder, fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA

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

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

    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

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres

    ESO E-ELT
    ESO/E-ELT to be built at Cerro Armazones at 3,060 m

    ESO APEX
    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert

     
  • richardmitnick 8:29 am on November 30, 2016 Permalink | Reply
    Tags: , , , ESO VLT, First Signs of Weird Quantum Property of Empty Space?, , RX J1856.5-3754   

    From ESO: “First Signs of Weird Quantum Property of Empty Space?” 

    ESO 50 Large

    European Southern Observatory

    30 November 2016
    Contacts

    Roberto Mignani
    INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica Milano
    Milan, Italy
    Tel: +39 02 23699 347
    Cell: +39 328 9685465
    Email: mignani@iasf-milano.inaf.it

    Vincenzo Testa
    INAF – Osservatorio Astronomico di Roma
    Monteporzio Catone, Italy
    Tel: +39 06 9428 6482
    Email: vincenzo.testa@inaf.it

    Roberto Turolla
    University of Padova
    Padova, Italy
    Tel: +39-049-8277139
    Email: turolla@pd.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

    VLT observations of neutron star may confirm 80-year-old prediction about the vacuum


    Access mp4 video here .

    1
    By studying the light emitted from an extraordinarily dense and strongly magnetised neutron star using ESO’s Very Large Telescope, astronomers may have found the first observational indications of a strange quantum effect, first predicted in the 1930s. The polarisation of the observed light suggests that the empty space around the neutron star is subject to a quantum effect known as vacuum birefringence.

    A team led by Roberto Mignani from INAF Milan (Italy) and from the University of Zielona Gora (Poland), used ESO’s Very Large Telescope (VLT) at the Paranal Observatory in Chile to observe the neutron star RX J1856.5-3754, about 400 light-years from Earth [1].

    4
    This wide field image shows the sky around the very faint neutron star RX J1856.5-3754 in the southern constellation of Corona Australis. This part of the sky also contains interesting regions of dark and bright nebulosity surrounding the variable star R Coronae Australis (upper left), as well as the globular star cluster NGC 6723. The neutron star itself is too faint to be seen here, but lies very close to the centre of the image. Credit: ESO/Digitized Sky Survey 2. Acknowledgement: Davide De Martin

    5
    Colour composite photo of the sky field around the lonely neutron star RX J1856.5-3754 and the related cone-shaped nebula. It is based on a series of exposures obtained with the multi-mode FORS2 instrument at VLT KUEYEN through three different optical filters.

    ESO FORS2 VLT
    ESO FORS2 VLT

    The trail of an asteroid is seen in the field with intermittent blue, green and red colours. RX J1856.5-3754 is exactly in the centre of the image. Credit: ESO

    Despite being amongst the closest neutron stars, its extreme dimness meant the astronomers could only observe the star with visible light using the FORS2 instrument on the VLT, at the limits of current telescope technology.

    Neutron stars are the very dense remnant cores of massive stars — at least 10 times more massive than our Sun — that have exploded as supernovae at the ends of their lives. They also have extreme magnetic fields, billions of times stronger than that of the Sun, that permeate their outer surface and surroundings.

    These fields are so strong that they even affect the properties of the empty space around the star. Normally a vacuum is thought of as completely empty, and light can travel through it without being changed. But in quantum electrodynamics (QED), the quantum theory describing the interaction between photons and charged particles such as electrons, space is full of virtual particles that appear and vanish all the time. Very strong magnetic fields can modify this space so that it affects the polarisation of light passing through it.

    Mignani explains: “According to QED, a highly magnetised vacuum behaves as a prism for the propagation of light, an effect known as vacuum birefringence.”

    Among the many predictions of QED, however, vacuum birefringence so far lacked a direct experimental demonstration. Attempts to detect it in the laboratory have not yet succeeded in the 80 years since it was predicted in a paper by Werner Heisenberg (of uncertainty principle fame) and Hans Heinrich Euler.

    “This effect can be detected only in the presence of enormously strong magnetic fields, such as those around neutron stars. This shows, once more, that neutron stars are invaluable laboratories in which to study the fundamental laws of nature.” says Roberto Turolla (University of Padua, Italy).

    After careful analysis of the VLT data, Mignani and his team detected linear polarisation — at a significant degree of around 16% — that they say is likely due to the boosting effect of vacuum birefringence occurring in the area of empty space surrounding RX J1856.5-3754 [2].

    Vincenzo Testa (INAF, Rome, Italy) comments: “This is the faintest object for which polarisation has ever been measured. It required one of the largest and most efficient telescopes in the world, the VLT, and accurate data analysis techniques to enhance the signal from such a faint star.”

    “The high linear polarisation that we measured with the VLT can’t be easily explained by our models unless the vacuum birefringence effects predicted by QED are included,” adds Mignani.

    “This VLT study is the very first observational support for predictions of these kinds of QED effects arising in extremely strong magnetic fields,” remarks Silvia Zane (UCL/MSSL, UK).

    Mignani is excited about further improvements to this area of study that could come about with more advanced telescopes: “Polarisation measurements with the next generation of telescopes, such as ESO’s European Extremely Large Telescope, could play a crucial role in testing QED predictions of vacuum birefringence effects around many more neutron stars.”

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile
    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile

    “This measurement, made for the first time now in visible light, also paves the way to similar measurements to be carried out at X-ray wavelengths,” adds Kinwah Wu (UCL/MSSL, UK).

    Notes

    [1] This object is part of the group of neutron stars known as the Magnificent Seven. They are known as isolated neutron stars (INS), which have no stellar companions, do not emit radio waves (like pulsars), and are not surrounded by progenitor supernova material.

    [2] There are other processes that can polarise starlight as it travels through space. The team carefully reviewed other possibilities — for example polarisation created by scattering off dust grains — but consider it unlikely that they produced the polarisation signal observed.

    More information

    This research was presented in the paper entitled Evidence for vacuum birefringence from the first optical polarimetry measurement of the isolated neutron star RX J1856.5−3754, by R. Mignani et al., to appear in Monthly Notices of the Royal Astronomical Society.

    The team is composed of R.P. Mignani (INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica Milano, Milano, Italy; Janusz Gil Institute of Astronomy, University of Zielona Góra, Zielona Góra, Poland), V. Testa (INAF – Osservatorio Astronomico di Roma, Monteporzio, Italy), D. González Caniulef (Mullard Space Science Laboratory, University College London, UK), R. Taverna (Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy), R. Turolla (Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy; Mullard Space Science Laboratory, University College London, UK), S. Zane (Mullard Space Science Laboratory, University College London, UK) and K. Wu (Mullard Space Science Laboratory, University College London, UK).

    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

     
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