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  • richardmitnick 1:44 pm on August 3, 2018 Permalink | Reply
    Tags: , , , , , ESO VLT, , Frank Eisenhauer,   

    From ESOblog: Advancing Technology for Galactic Observations 

    ESO 50 Large

    From ESOblog

    1
    Science Snapshots

    3 August 2018

    In May 2018, the star S2 made its closest approach to the black hole at the centre of the Milky Way. Observing this event was no easy task. The centre is full of dense dust clouds, impenetrable at visual wavelengths. The unique instruments GRAVITY and SINFONI, able to take highly precise measurements, needed to be developed for these observations. Frank Eisenhauer, a member of the Galactic Centre group at Max Planck Institute for Extraterrestrial Physics and principal investigator for GRAVITY and SINFONI, talks about observing the close approach of S2 in the second of a three blog post series.

    ESO GRAVITY in the VLTI

    ESO SINFONI


    ESO/SINFONI

    Q: Can you tell us a bit about what observations your team aimed to make about the galactic centre?

    A: We knew that the star S2 would make a close flyby of the black hole in the centre of the Milky Way in 2018, making it possible to study the effects predicted by Einstein’s theory of general relativity. We expected the motion of the star to deviate from a Keplerian orbit based on Newton’s laws. Our observations aimed to see these differences, so, to see any visible changes, we had to improve our observation accuracy by several orders of magnitude compared to previous measurements.

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    This simulation shows the orbits of stars very close to the supermassive black hole at the heart of the Milky Way. The area is a perfect laboratory to test gravitational physics and specifically Einstein´s general theory of relativity. Credit: ESO/L. Calçada/spaceengine.org

    Q: What did you and your team do to prepare for this year’s observations?

    A: Our instrument — GRAVITY — was finished about three years ago and arrived in Chile, the site of ESO’s telescopes. Then the most intense period started: making GRAVITY work together with all four telescopes of the Very Large Telescope (VLT). In the summer of 2016, we had our first observations of the galactic centre, which, for the first time, showed not only S2 but also the black hole with unprecedented resolution. Since then they have become our faithful companions whenever we visit for a look. For the closest approach in 2018, the team returned for further observations every month.


    Animation of the path that an incoming light ray traces through the GRAVITY instrument. Note the intricate design and complex interaction of the various components for the four telescopes. For interferometry to work, the light paths have to be superposed with a precision of a fraction of the wavelength – less than 1 micrometre.
    Credit: MPE

    4
    The VLTI Delay Lines, which lie below the ground at Paranal, inside a 168-m tunnel. They form an essential part of this very complicated optical system by ensuring that the light beams from several telescopes arrive in phase at the common interferometric focus. Credit: Enrico Sacchetti/ESO

    Q: What kind of telescope did the team use to observe the galactic centre?

    A: So, we needed a “super-telescope”, which we created by combining the four largest ESO telescopes of the Very Large Telescope (VLT) with a technique called interferometry. This technique is well established in radio astronomy, i.e. when observing at longer wavelengths, but many thought it would be impossible to achieve that level of sensitivity and accuracy at infrared wavelengths. And, yes, it was not easy. But the star would not wait for us — and in the end, we were ready in time!

    Q: Can you explain how infrared interferometry works?
    The optical path lengths between the four telescopes and our instrument have to be controlled with the precision of a fraction of the wavelength

    A: With an interferometer, you combine the light received from different telescopes. The big challenge is to combine this light properly, or “in phase” as the physicists say. This means that the optical path lengths between the four telescopes and our instrument have to be controlled with the precision of a fraction of the wavelength—several hundred times smaller than the thickness of a human hair—while the telescopes are separated by as much as 130 metres.


    Learn more about the first successful test of Einstein’s General Theory of Relativity near a supermassive black hole in ESOcast 173.
    Credit: MPE

    5
    Every day, before the observations start, each telescope undergoes a complete start up during which each of its function is checked, like a plane before take off. Here, Yepun, the fourth Unit Telescope, has been moved to a very low altitude, revealing the cell holding its main mirror and the SINFONI integral-field spectrograph. Credit: ESO

    Q: Can you tell us a bit about the ESO instruments used and the differences between them?

    A: The group around Reinhard Genzel at the Max Planck Institute for Extraterrestrial Physics (MPE) started to observe the galactic centre with the SHARP I camera on the New Technology Telescope in the 1990s. At that time, high-quality infrared detectors became available and we were the first to use them to peer through the dust cloud obscuring the galactic centre. Then came NACO with the VLT, which lead to the breakthrough with the first orbit measurement in 2002. In parallel, we developed SINFONI, the first near-infrared imaging spectrograph for the VLT, which has given us crucial velocity measurements since its installation in 2003. And, finally, GRAVITY now combines all four VLT telescope to a “130-m super-telescope.”

    Q: What about these instruments makes it possible to see through the curtain of dust and stars?

    A: The galactic centre is hidden behind dense dusts clouds — but this is only true for visible light. If you go to infrared wavelengths, you can see through to the stars beyond. However, part of this radiation is absorbed by the Earth’s atmosphere, and in particular water vapour in the air. This meant we needed to go to a high place, with less atmosphere above us, and a dry place, i.e. a desert. This is why the Paranal observatory, on top of a high mountain in the Atacama desert, was the perfect place for these observations. But even for the best observing conditions, the atmosphere’s turbulence blurs the images, which is why we need adaptive optics (AO).

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

    Q: Can you tell us a bit about the Adaptive Optics system for IR imaging? Are there any challenges using AO to observe the Galactic Centre?

    A: Adaptive optics means that you measure the distortion from the Earth’s atmosphere a few hundred times per second, and correct it in real time with a deformable mirror. For this, you need a bright reference star. Unfortunately, there are no really bright stars at visible wavelengths close to the galactic centre to measure these distortions. Therefore you have two options: create your own artificial star with a laser beacon, as done with SINFONI, or build an infrared wavefront sensor as we did for GRAVITY.

    Q: What advancements in observing technology have made it possible for us to study the galactic centre as compared to 20 or 25 years ago when observations of the galactic centre were really becoming possible?

    A: When the group at MPE started observing the galactic centre in the 1990s, we could observe with 150 milliarcsecond resolution. This is about the angle under which a stadium 300 metres diameter would appear on the Moon. Now, with GRAVITY, we can observe with a resolution as good as 2 milliarcseconds, and measure the separation between the star S2 and the black hole with a precision of just a few tens of microarcseconds. The latter is equivalent to observing two objects on the Moon that are separated by the length of a pencil.

    Q: What do you find most exciting about studying the galactic centre?

    A: To see so many miracles predicted by the general theory of relativity all in one place: the black hole, stars moving at incredible speed, the time dilation, and many other phenomena. The centre of the Milky Way is and will remain our Rosetta stone for deciphering these wonders.

    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.

    Leiden MASCARA instrument, La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level

    SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level

    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

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  • richardmitnick 12:42 pm on April 26, 2018 Permalink | Reply
    Tags: , , , , ESO VLT, , , Stellar Thief is the Surviving Companion to a Supernova   

    From NASA/ESA Hubble Telescope: “Stellar Thief is the Surviving Companion to a Supernova” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Apr 26, 2018

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

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

    Ori Fox
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-6768
    ofox@stsci.edu

    Stuart Ryder
    Australian Astronomical Observatory, Sydney, Australia
    011-61-2-93724843
    011-61-419-970834 (cell)
    sdr@aao.gov.au

    Alex Filippenko
    University of California, Berkeley, California
    afilippenko@berkeley.edu

    1
    Companion to a Supernova is No Innocent Bystander

    In the fading afterglow of a supernova explosion, astronomers using NASA’s Hubble Space Telescope have photographed the first image of a surviving companion to a supernova. This is the most compelling evidence that some supernovas originate in double-star systems. The companion to supernova 2001ig’s progenitor star was no innocent bystander to the explosion—it siphoned off almost all of the hydrogen from the doomed star’s stellar envelope. SN 2001ig is categorized as a Type IIb stripped-envelope supernova, which is a relatively rare type of supernova in which most, but not all, of the hydrogen is gone prior to the explosion. Perhaps as many as half of all stripped-envelope supernovas have companions—the other half lose their outer envelopes via stellar winds.

    3

    Seventeen years ago, astronomers witnessed a supernova go off 40 million light-years away in the galaxy called NGC 7424, located in the southern constellation Grus, the Crane. Now, in the fading afterglow of that explosion, NASA’s Hubble has captured the first image of a surviving companion to a supernova. This picture is the most compelling evidence that some supernovas originate in double-star systems.

    “We know that the majority of massive stars are in binary pairs,” said Stuart Ryder from the Australian Astronomical Observatory (AAO) in Sydney, Australia and lead author of the study. “Many of these binary pairs will interact and transfer gas from one star to the other when their orbits bring them close together.”

    The companion to the supernova’s progenitor star was no innocent bystander to the explosion. It siphoned off almost all of the hydrogen from the doomed star’s stellar envelope, the region that transports energy from the star’s core to its atmosphere. Millions of years before the primary star went supernova, the companion’s thievery created an instability in the primary star, causing it to episodically blow off a cocoon and shells of hydrogen gas before the catastrophe.

    The supernova, called SN 2001ig, is categorized as a Type IIb stripped-envelope supernova. This type of supernova is unusual because most, but not all, of the hydrogen is gone prior to the explosion. This type of exploding star was first identified in 1987 by team member Alex Filippenko of the University of California, Berkeley.

    How stripped-envelope supernovas lose that outer envelope is not entirely clear. They were originally thought to come from single stars with very fast winds that pushed off the outer envelopes. The problem was that when astronomers started looking for the primary stars from which supernovas were spawned, they couldn’t find them for many stripped-envelope supernovas.

    “That was especially bizarre, because astronomers expected that they would be the most massive and the brightest progenitor stars,” explained team member Ori Fox of the Space Telescope Science Institute in Baltimore. “Also, the sheer number of stripped-envelope supernovas is greater than predicted.” That fact led scientists to theorize that many of the primary stars were in lower-mass binary systems, and they set out to prove it.

    Looking for a binary companion after a supernova explosion is no easy task. First, it has to be at a relatively close distance to Earth for Hubble to see such a faint star. SN 2001ig and its companion are about at that limit. Within that distance range, not many supernovas go off. Even more importantly, astronomers have to know the exact position through very precise measurements.

    In 2002, shortly after SN 2001ig exploded, scientists pinpointed the precise location of the supernova with the European Southern Observatory’s Very Large Telescope (VLT) in Cerro Paranal, Chile. In 2004, they then followed up with the Gemini South Observatory in Cerro Pachón, Chile. This observation first hinted at the presence of a surviving binary companion.

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)

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


    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    Knowing the exact coordinates, Ryder and his team were able to focus Hubble on that location 12 years later, as the supernova’s glow faded. With Hubble’s exquisite resolution and ultraviolet capability, they were able to find and photograph the surviving companion—something only Hubble could do.

    Prior to the supernova explosion, the orbit of the two stars around each other took about a year.

    When the primary star exploded, it had far less impact on the surviving companion than might be thought. Imagine an avocado pit—representing the dense core of the companion star—embedded in a gelatin dessert—representing the star’s gaseous envelope. As a shock wave passes through, the gelatin might temporarily stretch and wobble, but the avocado pit would remain intact.

    In 2014, Fox and his team used Hubble to detect the companion of another Type IIb supernova, SN 1993J. However, they captured a spectrum, not an image. The case of SN 2001ig is the first time a surviving companion has been photographed. “We were finally able to catch the stellar thief, confirming our suspicions that one had to be there,” said Filippenko.

    Perhaps as many as half of all stripped-envelope supernovas have companions—the other half lose their outer envelopes via stellar winds. Ryder and his team have the ultimate goal of precisely determining how many supernovas with stripped envelopes have companions.

    Their next endeavor is to look at completely stripped-envelope supernovas, as opposed to SN 2001ig and SN 1993J, which were only about 90 percent stripped. These completely stripped-envelope supernovas don’t have much shock interaction with gas in the surrounding stellar environment, since their outer envelopes were lost long before the explosion. Without shock interaction, they fade much faster. This means that the team will only have to wait two or three years to look for surviving companions.

    In the future, they also hope to use the James Webb Space Telescope to continue their search.

    Added by Manu:

    4
    Evolution Envelope-Type IIb supernova Unobscured . This graphic illustrates the scenario for the processes that create a supernova envelope type IIb despoiled, in which most, but not all, of the hydrogen envelope is lost before the explosion of the primary star. The four panels show the interaction between SN 2001ig parent star, which finally exploded, and his surviving partner. 1) Two stars orbit each other and getting closer. 2) The more massive star evolves faster, swelling to become a red giant. In this last phase of life, sheds most of its hydrogen envelope in the gravitational field of his companion. As the companion extracted almost all the hydrogen from the doomed star, creates an instability in the primary star. 3) The primary star explodes in a supernova. 4) As the glow of the supernova fades, the surviving partner becomes visible to the Hubble Space Telescope. The faint supernova remnant in the lower left, continues to evolve, but in this case is too weak to be detected by Hubble.

    How supernovae surround the outer casing stripped lose is not entirely clear. Originally it thought it came from single stars with very high winds pushing the outer envelopes. The problem was that when astronomers began searching the primary star from which the supernovae were generated, they could not find in many supernovae devoid envelope.

    “That was especially strange because astronomers expected to be the biggest and brightest progenitor stars,” said team member Ori Fox Science Institute in Baltimore Space Telescope. “In addition, the large number of supernovae devoid envelope is greater than anticipated.” This led scientists to theorize that many of the primary stars in binary systems were lower mass, and prepared to try it.

    Find a binary companion after a supernova explosion is not an easy task. First, it has to be relatively close to Earth that Hubble distance to see such a faint star. SN 2001ig and his companion are at the limit. Within that range of distance, not many supernovae are triggered. More importantly, astronomers must know the exact position through very precise measurements.


    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.

    The paper on this team’s current work was published on March 28, 2018 in The Astrophysical Journal.

    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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    AURA Icon

    NASA image

     
  • richardmitnick 11:41 am on April 5, 2018 Permalink | Reply
    Tags: , , , , Dead Star Circled by Light, ESO VLT, , ,   

    From ESO: “Dead Star Circled by Light” 

    ESO 50 Large

    European Southern Observatory

    5 April 2018
    Frédéric P. A. Vogt
    ESO Fellow
    Santiago, Chile
    Email: fvogt@eso.org

    Elizabeth S. Bartlett
    ESO Fellow
    Santiago, Chile
    Email: ebartlet@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
    New images from ESO’s Very Large Telescope in Chile and other telescopes reveal a rich landscape of stars and glowing clouds of gas in one of our closest neighbouring galaxies, the Small Magellanic Cloud. The pictures have allowed astronomers to identify an elusive stellar corpse buried among filaments of gas left behind by a 2000-year-old supernova explosion. The MUSE instrument was used to establish where this elusive object is hiding, and existing Chandra X-ray Observatory data confirmed its identity as an isolated neutron star.

    ESO MUSE on the VLT

    NASA/Chandra Telescope

    Spectacular new pictures, created from images from both ground- and space-based telescopes [1], tell the story of the hunt for an elusive missing object hidden amid a complex tangle of gaseous filaments in the Small Magellanic Cloud, about 200 000 light-years from Earth.

    New data from the MUSE instrument on ESO’s Very Large Telescope in Chile has revealed a remarkable ring of gas in a system called 1E 0102.2-7219, expanding slowly within the depths of numerous other fast-moving filaments of gas and dust left behind after a supernova explosion. This discovery allowed a team led by Frédéric Vogt, an ESO Fellow in Chile, to track down the first ever isolated neutron star with low magnetic field located beyond our own Milky Way galaxy.

    The team noticed that the ring was centred on an X-ray source that had been noted years before and designated p1. The nature of this source had remained a mystery. In particular, it was not clear whether p1 actually lies inside the remnant or behind it. It was only when the ring of gas — which includes both neon and oxygen — was observed with MUSE that the science team noticed it perfectly circled p1. The coincidence was too great, and they realised that p1 must lie within the supernova remnant itself. Once p1’s location was known, the team used existing X-ray observations of this target from the Chandra X-ray Observatory to determine that it must be an isolated neutron star, with a low magnetic field.

    In the words of Frédéric Vogt: “If you look for a point source, it doesn’t get much better than when the Universe quite literally draws a circle around it to show you where to look.”

    When massive stars explode as supernovae, they leave behind a curdled web of hot gas and dust, known as a supernova remnant. These turbulent structures are key to the redistribution of the heavier elements — which are cooked up by massive stars as they live and die — into the interstellar medium, where they eventually form new stars and planets.

    Typically barely ten kilometres across, yet weighing more than our Sun, isolated neutron stars with low magnetic fields are thought to be abundant across the Universe, but they are very hard to find because they only shine at X-ray wavelengths [2]. The fact that the confirmation of p1 as an isolated neutron star was enabled by optical observations is thus particularly exciting.

    Co-author Liz Bartlett, another ESO Fellow in Chile, sums up this discovery: “This is the first object of its kind to be confirmed beyond the Milky Way, made possible using MUSE as a guidance tool. We think that this could open up new channels of discovery and study for these elusive stellar remains.”
    Notes

    [1] The image combines data from the MUSE instrument on ESO’s Very Large Telescope in Chile and the orbiting the NASA/ESA Hubble Space Telescope and NASA Chandra X-Ray Observatory.

    NASA/ESA Hubble Telescope

    [2] Highly-magnetic spinning neutron stars are called pulsars. They emit strongly at radio and other wavelengths and are easier to find, but they are only a small fraction of all the neutron stars predicted to exist.

    More information

    This research was presented in a paper entitled Identification of the central compact object in the young supernova remnant 1E 0102.2-7219, by Frédéric P. A. Vogt et al., in the journal Nature Astronomy.

    The team is composed of Frédéric P. A. Vogt (ESO, Santiago, Chile & ESO Fellow), Elizabeth S. Bartlett (ESO, Santiago, Chile & ESO Fellow), Ivo R. Seitenzahl (University of New South Wales Canberra, Australia), Michael A. Dopita (Australian National University, Canberra, Australia), Parviz Ghavamian (Towson University, Baltimore, Maryland, USA), Ashley J. Ruiter (University of New South Wales Canberra & ARC Centre of Excellence for All-sky Astrophysics, Australia) and Jason P. Terry (University of Georgia, Athens, USA).

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

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    Visit ESO in Social Media-

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    Twitter

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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

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

    ESO/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.

    Leiden MASCARA instrument, La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level

    SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level

    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

     
  • richardmitnick 9:53 am on March 26, 2018 Permalink | Reply
    Tags: , , , , ESO VLT,   

    From NASA Chandra: “NGC 1365: Chandra Sees Remarkable Eclipse of Black Hole” April 12, 2007 

    NASA Chandra Banner

    NASA/Chandra Telescope


    NASA Chandra

    April 12, 2007 [From before this blog]

    1
    Credit X-ray: NASA/CXC/CfA/INAF/Risaliti Optical: ESO/VLT

    Chandra observations of the galaxy NGC 1365 have captured a remarkable eclipse of the supermassive black hole at its center. A dense cloud of gas passed in front of the black hole, which blocked high-energy X-rays from material close to the black hole. This serendipitous alignment allowed astronomers to measure the size of the disk of material around the black hole, a relatively tiny structure on galactic scales. The Chandra image (shown in the inset) contains a bright X-ray source in the middle, which reveals the position of the supermassive black hole. An optical view of the galaxy from the European Southern Observatory’s Very Large Telescope shows the context of the Chandra data.

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)

    NGC 1365 contains a so-called active galactic nucleus, or AGN. Scientists believe that the black hole at the center of the AGN is fed by a steady stream of material, presumably in the form of a disk. Material just about to fall into a black hole should be heated to millions of degrees before passing over the event horizon, or point of no return. The process causes the disk of gas around the central black hole in NGC 1365 to produce copious X-rays, but the structure is much too small to resolve directly with a telescope. However, astronomers were able to measure the disk’s size by observing how long it took for the black hole to go in and out of the eclipse. This was revealed during a series of observations of NGC 1365 obtained every two days over a period of two weeks in April 2006. During five of the observations, high-energy X-rays from the central X-ray source were visible, but in the second one — corresponding to the eclipse — they were not.

    No science paper cited.

    See the full article here .

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    NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

     
  • richardmitnick 11:08 am on January 31, 2018 Permalink | Reply
    Tags: , , , , , ESO GRAAL, , ESO VLT, Sharper Images for VLT Infrared Camera   

    From ESO: “Sharper Images for VLT Infrared Camera” 

    ESO 50 Large

    European Southern Observatory

    30 January 2018
    Harald Kuntschner
    ESO, AOF Project Scientist
    Garching bei München, Germany
    Tel: +49 89 3200 6465
    Email: hkuntsch@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
    This image of the dramatic star formation region 30 Doradus, also known as the Tarantula Nebula, was created from a mosaic of images taken using the HAWK-I instrument working with the Adaptive optics Facility of ESO’s Very Large Telescope in Chile. The stars are significantly sharper than the same image without adaptive optics being used, and fainter stars can be seen.

    ESO’s Very Large Telescope (VLT) now has a second instrument working with the powerful Adaptive Optics Facility (AOF). The infrared instrument HAWK-I (High Acuity Wide-field K-band Imager) [1] is now also benefiting from sharper images and shorter exposure times. This follows the successful integration of the AOF with MUSE (the Multi Unit Spectroscopic Explorer).

    ESO HAWK-I on the ESO VLT

    ESO MUSE on the VLT

    The Adaptive Optics Facility (AOF) is a long-term project that is nearing completion on ESO’s Very Large Telescope (VLT). It provides adaptive optics correction for all the instruments attached to one of the VLT Unit Telescopes (UT4, also known as Yepun).

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

    Adaptive optics works to compensate for the blurring effect of the Earth’s atmosphere. This upgrade now enables HAWK-I to obtain sharper images, needing shorter exposure times than before to obtain similar results. By using the AOF, astronomers can now get good image quality with HAWK-I, even when the weather conditions are not perfect.

    Following a series of tests of the new system, the commissioning team of astronomers and engineers were rewarded with a series of spectacular images, including one of the Tarantula Nebula star-forming region in the Large Magellanic Cloud.

    The AOF, which made these observations possible, is composed of many parts working together. These include the Four Laser Guide Star Facility (4LGSF) and the UT4’s very thin deformable secondary mirror, which is able to change its shape [2] [3]. The 4LGSF shines four 22-watt laser beams into the sky to make sodium atoms in the upper atmosphere glow as bright points of light, forming artificial guide stars.

    Sensors in the adaptive optics module GRAAL (GRound layer Adaptive optics Assisted by Lasers) use these artificial guide stars to determine the atmospheric conditions.

    ESO Graal

    One thousand times per second, the AOF system calculates the correction that must be applied to the telescope’s deformable secondary mirror to compensate for the atmospheric disturbance.

    GRAAL corrects for the turbulence in the layer of atmosphere up to about 500 metres above the telescope — the “ground layer”. Depending on the conditions, atmospheric turbulence occurs at all altitudes, but studies have shown that the largest fraction of the disturbance occurs in the ground layer of the atmosphere.

    The corrections applied by the AOF rapidly and continuously improve the image quality by concentrating the light to form sharper images, allowing HAWK-I to resolve finer details and detect fainter stars than previously possible.

    MUSE and HAWK-I are not the only instruments that will benefit from the AOF; in future, the new instrument ERIS will be installed on the VLT. The AOF is also a pathfinder for adaptive optics on ESO’s Extremely Large Telescope (ELT).

    Notes

    [1] HAWK-I is a wide-field imager, an instrument that takes images of the sky in infrared wavelengths. This allows it to see inside interstellar dust and gas, which blocks optical light. The instrument uses four imaging chips simultaneously to achieve such a large field of view, capturing a wealth of information.

    [2] At just over one metre in diameter, this is the largest adaptive optics mirror in operation and demanded cutting-edge technology to make it. It was mounted on UT4 in 2016 (ann16078) to replace the telescope’s original conventional secondary mirror.

    [3] Other tools to optimise the operation of the AOF have been developed and are now operational. These include an extension of the Astronomical Site Monitor software that monitors the atmosphere to determine the altitude at which the turbulence is occurring, and the Laser Traffic Control System (LTCS) that prevents other telescopes looking into the laser beams or spots and potentially affecting their observations.

    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.

    Leiden MASCARA instrument, La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level

    SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level

    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

     
  • richardmitnick 2:27 pm on December 25, 2017 Permalink | Reply
    Tags: Astronomers Find Galaxy Cluster with Mass of Two Quadrillion Suns, , , , , ESO VLT, ,   

    From Science News: “Astronomers Find Galaxy Cluster with Mass of Two Quadrillion Suns” 

    SciNews

    Dec 25, 2017

    NASA and ESO astronomers have joined forces to observe RCS2 J2327-0204, one of the most massive galaxy clusters known at its distance or beyond.

    1
    The galaxy cluster RCS2 J2327-0204. Image credit: ESO / NASA / ESA / Hubble.

    RCS2 J2327-0204 is an extremely massive cluster of galaxies located approximately 6 billion light-years away.

    Massive objects such as RCS2 J2327-0204 have such a strong influence on their surroundings that they visibly warp the space around them. This effect is known as gravitational lensing.

    Gravitational Lensing NASA/ESA

    In this way, they cause the light from more distant objects to be bent, distorted, and magnified, allowing us to see galaxies that would otherwise be far too distant to detect.

    Gravitational lensing is one of the predictions of Albert Einstein’s theory of general relativity.

    Strong lensing produces stunning images of distorted galaxies and sweeping arcs; both of which can be seen in this image.

    Weak gravitational lensing, on the other hand, is more subtle, hardly seen directly in an image, and is mostly studied statistically — but it provides a way to measure the masses of cosmic objects, as in the case of this cluster.

    This image of RCS2 J2327-0204 is a composite of observations from the HAWK-I instrument on ESO’s Very Large Telescope and the Advanced Camera for Surveys (ACS) instrument on the NASA/ESA Hubble Space Telescope.

    ESO HAWK-I on the ESO VLT


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

    NASA/ESA Hubble ACS

    NASA/ESA Hubble Telescope

    It demonstrates an impressively detailed collaborative approach to studying weak lensing in the cosmos.

    The astronomers found RCS2 J2327-0204 to contain the mass of two quadrillion Suns.

    The diffuse blue and white image covering the picture shows a mass map. It is connected to the amount of mass thought to be contained within each region.

    See the full article here .

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  • richardmitnick 8:43 am on October 4, 2017 Permalink | Reply
    Tags: , , , , , ESO VLT,   

    From CNRS: “MATISSE to shed light on the formation of Earth and planets” 

    CNRS bloc

    Centre Nationnal de la Recherche Scientifique [The National Center for Scientific Research ]

    25 September 2017
    Contacts:
    Researcher Observatoire Côte d’Azur
    Bruno Lopez
    bruno.lopez@oca.eu

    Press:
    Observatoire Côte d’Azur
    Marc Fulconis
    marc.fulconis@oca.eu

    CNRS Press Office
    Julien Guillaume
    T +33 1 44 96 46 35
    julien.guillaume@cnrs-dir.fr

    The MATISSE instrument is ready to be sent to Chile, where in the next few weeks it will be installed on the Very Large Telescope (VLT), the world’s most powerful astronomical observatory.

    ESO CNRS VLT Matisse Multi-AperTure mid-Infrared SpectroScopic Experiment

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

    This achievement is the outcome of fifteen years of development, including a final year of testing at the Laboratoire J.-L. Lagrange (Observatoire Côte d’Azur/CNRS/Université de Nice Sophia-Antipolis). The instrument, for which France is responsible under the auspices of the European Southern Observatory (ESO), is international in scope. By observing the protoplanetary disks that surround young stars, the MATISSE project should improve our understanding of the formation of the Earth and of planets in general.

    MATISSE is one of the few projects for which France has responsibility under the auspices of the ESO. In early October 2017, the MATISSE (Multi AperTure mid-Infrared SpectroScopic Experiment) instrument will travel to the Atacama desert in Chile to be installed on the ESO’s Very Large Telescope (VLT), the world’s most powerful astronomical observatory. Eight to ten months’ performance validation observing the sky under real conditions will then be required before the instrument is made available to the international astronomical community.

    With MATISSE, one of the major goals of researchers is to observe protoplanetary disks in order to understand the formation of our own planet and that of planets in general. To achieve this, the instrument will enable astronomers to observe the sky with unprecedented resolution in the mid-infrared region—at wavelengths of 3 to 13 micrometers—and to combine the light from four of the VLT’s eight telescopes at Cerro Paranal, Chile, including the four large eight-meter telescopes. Using the instrument it will be possible to observe the dust and gas surrounding young stars that make up the basic building blocks from which planets form. The environments of stars younger than our own Sun, which have been difficult to observe until now, should shed light on the conditions under which different types of planets form: gas giants like Jupiter, and smaller rocky planets like Earth.

    MATISSE will operate in the same range of wavelengths as the James Webb Space Telescope, which will be launched in 2019 by NASA, and to which it is complementary. NASA researchers are already collaborating with the MATISSE consortium in order to step up joint research.

    NASA/ESA/CSA Webb Telescope annotated

    A number of European organizations were involved in developing the project: the Observatoire de la Côte d’Azur (OCA) and the CNRS in France, the MPIA, MPIfR and ESO in Germany, and NOVA-ASTRON in the Netherlands.

    Status

    Preliminary acceptance Chile: 2019
    First light on telescope: Early 2018
    Now
    Preliminary acceptance Europe: September 2017
    Final Design Review, March 2012
    Optical and Cryogenics Final Design Review, September 2011
    Preliminary Design Review, December 2010

    Baseline Specification
    Requirement
    Optical Throughput 15% (goal 25%) in L and N band
    Wavelength coverage L, M and N band
    Spectral Resolution 20< R <1000 in L band, 20 < R <550 in M band and 20 < R < 250 in N band
    Field of View n/a
    Spatial Sampling n/a
    Interferometric Contrast 0.6 (goal 0.75) in L and N band
    Observing modes High Sensitivity (HighSens) and Simultaneous Photometry (SiPhot)

    See the full article here .

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    CNRS encourages collaboration between specialists from different disciplines in particular with the university thus opening up new fields of enquiry to meet social and economic needs. CNRS has developed interdisciplinary programs which bring together various CNRS departments as well as other research institutions and industry.

    Interdisciplinary research is undertaken in the following domains:

    Life and its social implications
    Information, communication and knowledge
    Environment, energy and sustainable development
    Nanosciences, nanotechnologies, materials
    Astroparticles: from particles to the Universe

     
  • 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, ,   

    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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    The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.

     
  • 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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