Tagged: ESO Paranal VLT Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 12:45 pm on October 12, 2017 Permalink | Reply
    Tags: , , , , , ESO Paranal VLT, , , Prolate rotator galaxies   

    From Max Planck Institute for Astronomy: “Astronomers discover unusual spindle-like galaxies” 

    Max Planck Institute for Astronomy

    Max Planck Institute for Astronomy

    October 12, 2017
    Science Contact
    Athanasia Tsatsi
    tsatsi@mpia-hd.mpg.de

    Public Information Officer
    Markus Pössel
    Public Information Officer
    Phone:(+49|0) 6221 528-261
    poessel@hda-hd.de

    Galaxies are majestic, rotating wheels of stars? Not in the case of the spindle-like galaxies studied by Athanasia Tsatsi (Max Planck Institute for Astronomy) and her colleagues. Using the CALIFA survey, the astronomers found that these slender galaxies, which rotate along their longest axis, are much more common than previously thought. The new data allowed the astronomers to create a model for how these unusual galaxies probably formed, namely out of a special kind of merger of two spiral galaxies. The results have been published in the journal Astronomy & Astrophysics.

    1
    An elliptical galaxy in prolate rotation. The galaxy resembles the shape of a cigar, with its stars rotating around the galaxy’s long axis, similar to a spindle. the background image is a snapshot of a simulation by A. Tsatsi and colleagues.
    Image: J. Chang, PMO / T. Müller, HdA

    When most people think of galaxies, they think of majestic spiral galaxies like that of our home galaxy, the Milky Way: billions of stars, rotating in a flat disk similar to the way that a wheel rotates around its central axis. But there is another kind of galaxy, which used to be thought very rare: so-called prolate rotators, each shaped like a cigar, which rotates along its long axis, like a spindle.

    Now, a group of astronomers led by Athanasia Tsatsi of the Max Planck Institute for Astronomy has completed a thorough study of these cosmic spindles. Using data from the CALIFA survey, a systematic study that examined the velocity structure of more than 600 galaxies, the astronomers discovered eight new prolate rotating galaxies, almost doubling the total known number of such galaxies (from 12 to 20). Cosmic spindles are considerably less rare than astronomers had thought!

    Given the high quality of their data, the astronomers were able to propose a plausible explanation for how these cosmic spindles come into existence. In general, galaxies grow when they merge with other galaxies. Several mergers with smaller galaxies have made our own Milky Way the stately disk it is today. To make a cosmic spindle, two large disk galaxies need to collide at right angles, as shown in this animation:


    Movie: J. Chang, PMO / T. Müller, HdA

    The formation of an elliptical galaxy in prolate rotation. The mechanism shown here was proposed by Athanasia Tsatsi and her colleagues in order to explain the recent discoveries of galaxies of this kind with the CALIFA survey. The formation involves a polar merger of two spiral galaxies. One of the spiral galaxies develops a marked elongated structure (a “bar,” to use the technical term) before the merger, which gives the resulting elliptical galaxy its cigar-like (prolate) shape. The stars of the second spiral galaxy end up orbiting around the bar of the first companion. Together they form a cigar-shaped elliptical galaxy that rotates like a spindle around its long axis.

    As the galaxies begin to interact via gravitational attraction, one of them forms a bar: an elongated structure near the center. That bar becomes the cigar-like shape of the merged galaxy, while the orbiting stars of the other galaxy imbue the merged galaxy with its overall sense of rotation.

    The results are an interesting piece of the puzzle, explaining a likely formation scenario for an unusual, but not all that uncommon type of galaxy. Tsatsi’s team of researchers having put to good use all the information contained in the CALIFA data, the ball is now in the court of the observing astronomers again: the merger simulations make some additional predictions for the detailed properties of prolate rotators. These cannot be distinguished with the current observations, but could be tested with instruments like MUSE, the Multi Unit Spectral Explorer at ESO’s Very Large Telescope, an 8-meter-telescope at Paranal Observatory in Chile.

    ESO MUSE on the VLT


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

    The team members are Athanasia Tsatsi, Glenn van de Ven, and Andrea V. Macciò (also New York University Abu Dhabi) in collaboration with Mariya Lyubenova (University of Groningen, Netherland, now at ESO), J. Chang (Purple Mountain Observatory, Nanjing, China), J. A. L. Aguerri and J. Falcón-Barroso (both Instituto de Astrofísica de Canarias and Universidad de La Laguna, Tenerife, Spain).

    Calar Alto Observatory was founded in 1979 and is located in Andalusia, Spain.

    Calar Alto Observatory located in Almería province in Spain on Calar Alto, a 2,168-meter-high (7,113 ft) mountain in Sierra de Los Filabres

    It is operated jointly by the Max Planck Institute for Astronomy (MPIA) and the Astrophysical Institute of Andalusia (IAA-CSIC, Granada, Spain). The Observatory has granted 250 observing nights over the course of three years, using the 3.5 metre telescope for the CALIFA survey. This project is a joint effort of more than 80 scientists from 25 different research institutes in 13 different countries world wide.

    The integral field spectrograph used for the CALIFA survey at Calar Alto Observatory, PMAS (in a special configuration called PPAK), uses more than 350 optical fibres to cover a field of view of one square arcminute (equivalent to the apparent size of a 1 euro coin placed at a distance of approximately 80 metres). This allows a complete extended object, such as a galaxy, to be fully mapped in detail in just one exposure.

    For the CALIFA survey, care has been taken to select the possible observation targets at random from the overall population of galaxies. In that way, the galaxies under study should be representative of the whole: Statistical conclusions from the analysis of their data should thus allow astronomers to draw conclusions about local galaxies in general.

    The CALIFA member institutions are: Astrophysical Institute, Academy of Sciences of the Czech Republic, Prague; Australian Astronomical Observatory, Australia; Centro Astronómico Hispano Alemán, Spain; Centro de Astrofísica da Universidade do Porto, Portugal; Institut d’Astrophysique de Paris, France; Instituto de Astrofisica de Andalucia, Spain; Instituto de Astrofisica de Canarias, Spain; Instituto de Física de Cantabria, Spain; Laboratoire d’Astrophysique de Marseille, France; Leibniz Institut für Astrophysik, Potsdam, Germany; Max Planck Institute for Astronomy, Heidelberg, Germany; Observatoire de Paris, France; Peking University – Kavli Institute for Astronomy and Astrophysics, China; Royal Military College of Canada, Canada; Tianjin Normal University, China; Universidad Autónoma de Madrid, Spain; Universidad de Complutense de Madrid, Spain; Universidad de Granada, Spain; Universidad de Zaragoza, Spain; University of Bochum, Germany; University of Cambridge, UK; University of Copenhagen – Dark Cosmology Centre, Denmark; University of Edingurgh, UK; University of Groningen – Kapteyn Astronomical Institute, The Netherlands; University of Heidelberg – Landessternwarte Königstuhl, Germany; University of Lisbon, Portugal; University of Missouri-Kansas City, USA; University of Porto, Portugal; University of Sidney, Australia; University of Vienna, Austria

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Advertisements
     
  • richardmitnick 6:51 am on September 27, 2017 Permalink | Reply
    Tags: , , , , ESO Paranal VLT, , The Strange Structures of the Saturn Nebula   

    From ESO: “The Strange Structures of the Saturn Nebula” 

    ESO 50 Large

    European Southern Observatory

    27 September 2017
    Jeremy Walsh
    ESO
    Garching bei München, Germany
    jwalsh@eso.org

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

    1
    The spectacular planetary nebula NGC 7009, or the Saturn Nebula, emerges from the darkness like a series of oddly-shaped bubbles, lit up in glorious pinks and blues. This colourful image was captured by the powerful MUSE instrument on ESO’s Very Large Telescope (VLT), as part of a study which mapped the dust inside a planetary nebula for the first time. This annotated version labels the features of this curious object. Credit: ESO/J. Walsh

    ESO MUSE on the VLT

    The map — which reveals a wealth of intricate structures in the dust, including shells, a halo and a curious wave-like feature — will help astronomers understand how planetary nebulae develop their strange shapes and symmetries.

    2
    This view shows how the MUSE instrument on ESO’s Very Large Telescope gives a three-dimensional depiction of the Saturn Nebula. For each part of this spectacular nebula, the light has been split up into its component colours — revealing in detail the chemical and physical properties of each pixel. During the subsequent analysis the astronomer can move through the data and study different views of the object at different wavelengths, just like tuning a television to different channels at different frequencies. Credit: ESO/J. Walsh


    Credit: ESO.
    Directed by: Nico Bartmann.
    Editing: Nico Bartmann.
    Web and technical support: Mathias André and Raquel Yumi Shida.
    Written by: Izumi Hansen and Richard Hook.
    Music: John Stanford (johnstanfordmusic.com).
    Footage and photos: ESO, Digitized Sky Survey 2, N. Risinger (skysurvey.org), J. Walsh, L. Calçada.
    Executive producer: Lars Lindberg Christensen.

    The Saturn Nebula is located approximately 5000 light years away in the constellation of Aquarius (The Water Bearer). Its name derives from its odd shape, which resembles everyone’s favourite ringed planet seen edge-on.

    But in fact, planetary nebulae have nothing to do with planets. The Saturn Nebula was originally a low-mass star, which expanded into a red giant at the end of its life and began to shed its outer layers. This material was blown out by strong stellar winds and energised by ultraviolet radiation from the hot stellar core left behind, creating a circumstellar nebula of dust and brightly-coloured hot gas. At the heart of the Saturn Nebula lies the doomed star, visible in this image, which is in the process of becoming a white dwarf [1].

    In order to better understand how planetary nebulae are moulded into such odd shapes, an international team of astronomers led by Jeremy Walsh from ESO used the Multi Unit Spectroscopic Explorer (MUSE) to peer inside the dusty veils of the Saturn Nebula. MUSE is an instrument installed on one of the four Unit Telescopes of the Very Large Telescope at ESO’s Paranal Observatory in Chile. It is so powerful because it doesn’t just create an image, but also gathers information about the spectrum — or range of colours — of the light from the object at each point in the image.

    The team used MUSE to produce the first detailed optical maps of the gas and dust distributed throughout a planetary nebula [2]. The resulting image of the Saturn Nebula reveals many intricate structures, including an elliptical inner shell, an outer shell, and a halo. It also shows two previously imaged streams extending from either end of the nebula’s long axis, ending in bright ansae (Latin for “handles”).

    Intriguingly, the team also found a wave-like feature in the dust, which is not yet fully understood. Dust is distributed throughout the nebula, but there is a significant drop in the amount of dust at the rim of the inner shell, where it seems that it is being destroyed. There are several potential mechanisms for this destruction. The inner shell is essentially an expanding shock wave, so it may be smashing into the dust grains and obliterating them, or producing an extra heating effect that evaporates the dust.

    Mapping the gas and dust structures within planetary nebulae will aid in understanding their role in the lives and deaths of low mass stars, and it will also help astronomers understand how planetary nebulae acquire their strange and complex shapes.

    But MUSE’s capabilities extend far beyond planetary nebulae. This sensitive instrument can also study the formation of stars and galaxies in the early Universe, as well as map the dark matter distribution in galaxy clusters in the nearby Universe. MUSE has also created the first 3D map of the Pillars of Creation in the Eagle Nebula (eso1518) and imaged a spectacular cosmic crash in a nearby galaxy (eso1437).
    Notes

    [1] Planetary nebulae are generally short-lived; the Saturn Nebula will last only a few tens of thousands of years before expanding and cooling to such an extent that it becomes invisible to us. The central star will then fade as it becomes a hot white dwarf.

    [2] The NASA/ESA Hubble Space Telescope has previously provided a spectacular image of the Saturn Nebula — but, unlike MUSE, it cannot reveal the spectrum at each point over the whole nebula.
    More information

    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
    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

     
  • richardmitnick 2:10 pm on September 15, 2017 Permalink | Reply
    Tags: , , , ESO Paranal VLT, Matisse   

    From ESO: “Next-generation VLTI Instrument MATISSE Heads for Paranal” 

    ESO 50 Large

    European Southern Observatory

    1
    MATISSE, the Multi-AperTure mid-Infrared SpectroScopic Experiment, has passed a suite of initial tests conducted at the Observatoire de la Côte d’Azur in France and will now be transported to Chile for integration into the Very Large Telescope Interferometer (VLTI) at ESO’s Paranal Observatory.

    MATISSE is a four-way beam combiner, meaning that it will combine the light collected by up to four of the eight telescopes that make up the VLTI, and perform both spectroscopic and imaging observations. In so doing, MATISSE and the VLTI will together possess the imaging power of a telescope up to 200 metres in diameter, depending on the telescope configuration, and will be capable of producing stunningly detailed images. MATISSE will observe infrared light from the L-band to the N-band, which lie between visible and microwave wavelengths in the electromagnetic spectrum. The instrument is designed to contribute to several fundamental research areas in astronomy, focusing on the inner regions of discs around young stars where planets are forming, the study of stars at different stages of their lives, and the environment around black holes in active galactic nuclei (AGN).

    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
    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

     
  • richardmitnick 9:43 am on September 11, 2017 Permalink | Reply
    Tags: , , , , , ESO Paranal VLT, WASP-19b   

    From ESO: “Inferno World with Titanium Skies” 

    ESO 50 Large

    European Southern Observatory

    13 September 2017
    Elyar Sedaghati
    ESO Fellow
    Vitacura, Santiago, Chile
    Tel: +56 2 2463 6537
    Email: esedagha@eso.org

    Henri Boffin
    ESO
    Garching bei München, Germany
    Tel: +49 89 3200 6542
    Email: hboffin@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
    Astronomers using ESO’s Very Large Telescope have detected titanium oxide in an exoplanet atmosphere for the first time. This discovery around the hot-Jupiter planet WASP-19b exploited the power of the FORS2 instrument. It provides unique information about the chemical composition and the temperature and pressure structure of the atmosphere of this unusual and very hot world. The results appear today in the journal Nature.

    ESO FORS2 VLT

    A team of astronomers led by Elyar Sedaghati, an ESO fellow and recent graduate of TU Berlin, has examined the atmosphere of the exoplanet WASP-19b in greater detail than ever before. This remarkable planet has about the same mass as Jupiter, but is so close to its parent star that it completes an orbit in just 19 hours and its atmosphere is estimated to have a temperature of about 2000 degrees Celsius.

    2
    As WASP-19b passes in front of its parent star, some of the starlight passes through the planet’s atmosphere and leaves subtle fingerprints in the light that eventually reaches Earth. By using the FORS2 instrument on the Very Large Telescope the team was able to carefully analyse this light and deduce that the atmosphere contained small amounts of titanium oxide, water and traces of sodium, alongside a strongly scattering global haze.

    “Detecting such molecules is, however, no simple feat,” explains Elyar Sedaghati, who spent 2 years as ESO student to work on this project. “Not only do we need data of exceptional quality, but we also need to perform a sophisticated analysis. We used an algorithm that explores many millions of spectra spanning a wide range of chemical compositions, temperatures, and cloud or haze properties in order to draw our conclusions.”

    Titanium oxide is rarely seen on Earth. It is known to exist in the atmospheres of cool stars. In the atmospheres of hot planets like WASP-19b, it acts as a heat absorber. If present in large enough quantities, these molecules prevent heat from entering or escaping through the atmosphere, leading to a thermal inversion — the temperature is higher in the upper atmosphere and lower further down, the opposite of the normal situation. Ozone plays a similar role in Earth’s atmosphere, where it causes inversion in the stratosphere.

    “The presence of titanium oxide in the atmosphere of WASP-19b can have substantial effects on the atmospheric temperature structure and circulation.” explains Ryan MacDonald, another team member and an astronomer at Cambridge University, United Kingdom. “To be able to examine exoplanets at this level of detail is promising and very exciting.” adds Nikku Madhusudhan from Cambridge University who oversaw the theoretical interpretation of the observations.

    The astronomers collected observations of WASP-19b over a period of more than one year. By measuring the relative variations in the planet’s radius at different wavelengths of light that passed through the exoplanet’s atmosphere and comparing the observations to atmospheric models, they could extrapolate different properties, such as the chemical content, of the exoplanet’s atmosphere.

    This new information about the presence of metal oxides like titanium oxide and other substances will allow much better modeling of exoplanet atmospheres. Looking to the future, once astronomers are able to observe atmospheres of possibly habitable planets, the improved models will give them a much better idea of how to interpret those observations.

    “This important discovery is the outcome of a refurbishment of the FORS2 instrument that was done exactly for this purpose,” adds team member Henri Boffin, from ESO, who led the refurbishment project. “Since then, FORS2 has become the best instrument to perform this kind of study from the ground.”
    More information

    This research was presented in the paper entitled “Detection of titanium oxide in the atmosphere of a hot Jupiter” by Elyar Sedaghati et. al. to appear in Nature.

    The team is composed of Elyar Sedaghati (ESO; Deutsches Zentrum für Luft- und Raumfahrt, Germany; and TU Berlin, Germany), Henri M.J. Boffin (ESO), Ryan J. MacDonald (Cambridge University, UK), Siddharth Gandhi (Cambridge University, UK), Nikku Madhusudhan (Cambridge University, UK), Neale P. Gibson (Queen’s University Belfast, UK), Mahmoudreza Oshagh (Georg-August-Universität Göttingen, Germany), Antonio Claret (Instituto de Astrofísica de Andalucía – CSIC, Spain) and Heike Rauer (Deutsches Zentrum für Luft- und Raumfahrt, Germany and TU Berlin, Germany).

    See the full article here .

    3
    https://wasp-planets.net/tag/wasp-19b/

    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.

    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)

     
  • richardmitnick 1:53 pm on August 9, 2017 Permalink | Reply
    Tags: , , , , , ESO Paranal VLT, The star S2   

    From ESO: “First Evidence for Relativity Effects in Stars Orbiting Supermassive Black Hole at Centre of Galaxy” 

    ESO 50 Large

    European Southern Observatory

    9 August 2017
    Marzieh Parsa
    I. Physikalisches Institut, Universität zu Köln
    Köln, Germany
    Tel: +49(0)221/470-3495
    Email: parsa@ph1.uni-koeln.de

    Andreas Eckart
    I. Physikalisches Institut, Universität zu Köln
    Köln, Germany
    Tel: +49(0)221/470-3546
    Email: eckart@ph1.uni-koeln.de

    Vladimir Karas
    Astronomical Institute, Academy of Science
    Prague, Czech Republic
    Tel: +420-226 258 420
    Email: vladimir.karas@cuni.cz

    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
    A new analysis of data from ESO’s Very Large Telescope and other telescopes [I have asked ESO repeatedly to credit all telscopes used in any project, as they are all supported by public money. They apparently prefer to leave us in the dark.] they reveals for the first time that the orbits of stars around the supermassive black hole at the centre of the Milky Way show the subtle effects predicted by Einstein’s general theory of relativity. The orbit of the star S2 is found to be deviating slightly from the path calculated using classical physics. This tantalising result is a prelude to much more precise measurements and tests of relativity that will be made using the GRAVITY instrument as star S2 passes very close to the black hole in 2018.

    ESO GRAVITY insrument on The VLT

    This artist’s impression shows the orbits of three of the stars very close to the supermassive black hole at the centre of the Milky Way. Analysis of data from ESO’s Very Large Telescope and other telescopes has revealed that the orbits of these stars show the subtle effects predicted by Einstein’s general theory of relativity. The orbit of the star called S2 is found to be deviating slightly from the path calculated using classical physics.
    The position of the supermassive black hole is marked with a white circle with a blue halo. Credit: ESO/M. Parsa/L. Calçada


    The orbit of the star S2 is found to be deviating slightly from the path calculated using classical physics. This tantalising result is a prelude to much more precise measurements and tests of relativity that will be made using the GRAVITY instrument as star S2 passes very close to the black hole in 2018.

    At the centre of the Milky Way, 26 000 light-years from Earth, lies the closest supermassive black hole, which has a mass four million times that of the Sun. This monster is surrounded by a small group of stars orbiting at high speed in the black hole’s very strong gravitational field. It is a perfect environment in which to test gravitational physics, and particularly Einstein’s general theory of relativity.

    A team of German and Czech astronomers have now applied new analysis techniques to the very rich set of existing observations of the stars orbiting the black hole, accumulated using ESO’s Very Large Telescope (VLT) in Chile and others over the last twenty years [1]. They compare the measured star orbits to predictions made using classical Newtonian gravity as well as predictions from general relativity.

    The team found evidence for a small change in the motion of one of the stars, known as S2, that is consistent with the predictions of general relativity [2]. The change due to relativistic effects amounts to only a few percent in the shape of the orbit, as well as only about one sixth of a degree in the orientation of the orbit [3]. This is the first time that a measurement of the strength of the general relativistic effects has been achieved for stars orbiting a supermassive black hole.

    Marzieh Parsa, PhD student at the University of Cologne, Germany and lead author of the paper [The Astropysical Journel], is delighted: “The Galactic Centre really is the best laboratory to study the motion of stars in a relativistic environment. I was amazed how well we could apply the methods we developed with simulated stars to the high-precision data for the innermost high-velocity stars close to the supermassive black hole.”

    3
    The central parts of our Galaxy, the Milky Way, as observed in the near-infrared with the NACO instrument on ESO’s Very Large Telescope. The position of the centre, which harbours the (invisible) black hole known as Sgr A*,with a mass 4 million times that of the Sun, is marked by the orange cross.

    The star S2 will make a close pass around the black hole in 2018 when it will be used as a unique probe of the strong gravity and act as a test of Einstein’s general theory of relativity. Credit: ESO/MPE/S. Gillessen et al.

    The high accuracy of the positional measurements, made possible by the VLT’s near-infrared adaptive optics instruments, was essential for the success of the study [4]. These were vital not only during the star’s close approach to the black hole, but particularly during the time when S2 was further away from the black hole. The latter data allowed an accurate determination of the shape of the orbit and how it is changing under the influence of relativity.

    “During the course of our analysis we realised that to determine relativistic effects for S2 one definitely needs to know the full orbit to very high precision,” comments Andreas Eckart, team leader at the University of Cologne.

    As well as more precise information about the orbit of the star S2, the new analysis also gives the mass of the black hole and its distance from Earth to a higher degree of accuracy [5].

    Co-author Vladimir Karas from the Academy of Sciences in Prague, the Czech Republic, is excited about the future: “It is very reassuring that S2 shows relativistic effects as expected on the basis of its proximity to the extreme mass concentration at the centre of the Milky Way. This opens up an avenue for more theory and experiments in this sector of science.”

    This analysis is a prelude to an exciting period for observations of the Galactic Centre by astronomers around the world. During 2018 the star S2 will make a very close approach to the supermassive black hole. This time the GRAVITY instrument, developed by a large international consortium led by the Max-Planck-Institut für extraterrestrische Physik in Garching, Germany [6], and installed on the VLT Interferometer [7], will be available to help measure the orbit much more precisely than is currently possible. Not only is this expected to reveal the general relativistic effects very clearly, but also it will allow astronomers to look for deviations from general relativity that might reveal new physics.
    Notes

    [1] Data from the near-infrared NACO camera now at VLT Unit Telescope 1 (Antu) and the near-infrared imaging spectrometer SINFONI at the Unit Telescope 4 (Yepun) were used for this study. Some additional published data obtained at the Keck Observatory were also used.

    ESO/NACO

    ESO/SINFONI


    Keck Observatory, Maunakea, Hawaii, USA

    [2] S2 is a 15-solar-mass star on an elliptical orbit around the supermassive black hole. It has a period of about 15.6 years and gets as close as 17 light-hours to the black hole — or just 120 times the distance between the Sun and the Earth.

    [3] A similar, but much smaller, effect is seen in the changing orbit of the planet Mercury in the Solar System. That measurement was one of the best early pieces of evidence in the late nineteenth century suggesting that Newton’s view of gravity was not the whole story and that a new approach and new insights were needed to understand gravity in the strong-field case. This ultimately led to Einstein publishing his general theory of relativity, based on curved spacetime, in 1915.

    When the orbits of stars or planets are calculated using general relativity, rather than Newtonian gravity, they evolve differently. Predictions of the small changes to the shape and orientation of orbits with time are different in the two theories and can be compared to measurements to test the validity of general relativity.

    [4] An adaptive optics system compensates for the image distortions produced by the turbulent atmosphere in real time and allows the telescope to be used at much angular resolution (image sharpness), in principle limited only by the mirror diameter and the wavelength of light used for the observations.

    [5] The team finds a black hole mass of 4.2 × 106 times the mass of the Sun, and a distance from us of 8.2 kiloparsecs, corresponding to almost 27 000 light-years.

    [6] The University of Cologne is part of the GRAVITY team (http://www.mpe.mpg.de/ir/gravity) and contributed the beam combiner spectrometers to the system.

    [7] GRAVITY First Light was in early 2016 and it is already observing the Galactic Centre.

    The team is composed of Marzieh Parsa, Andreas Eckart (I.Physikalisches Institut of the University of Cologne, Germany; Max Planck Institute for Radio Astronomy, Bonn, Germany), Banafsheh Shahzamanian (I.Physikalisches Institut of the University of Cologne, Germany), Christian Straubmeier (I.Physikalisches Institut of the University of Cologne, Germany), Vladimir Karas (Astronomical Institute, Academy of Science, Prague, Czech Republic), Michal Zajacek (Max Planck Institute for Radio Astronomy, Bonn, Germany; I.Physikalisches Institut of the University of Cologne, Germany) and J. Anton Zensus (Max Planck Institute for Radio Astronomy, Bonn, Germany).

    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
    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)

     
    • Jose 3:04 pm on September 20, 2017 Permalink | Reply

      Here you may find a simple post-Newtonian solution for Mercury’s orbit precession
      Gravity is a little big bigger than in Newton’s law; it increases with speed -kinetic energy- where the maximum is the double gravity in the case of light.
      Global Physics also predicts the anomalous precession of Mercury’s orbit as Paul Gerber did 20 years before Einstein. https://molwick.com/en/gravitation/077-mercury-orbit.html

      Like

  • richardmitnick 9:19 am on August 2, 2017 Permalink | Reply
    Tags: , , , , , Cutting-edge Adaptive Optics Facility Sees First Light, , ESO Paranal VLT   

    From ESO: “Cutting-edge Adaptive Optics Facility Sees First Light” 

    ESO 50 Large

    European Southern Observatory

    2 August 2017
    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

    Joël Vernet
    ESO MUSE and GALACSI Project Scientist
    Garching bei München, Germany
    Tel: +49 89 3200 6579
    Email: jvernet@eso.org

    1
    The Unit Telescope 4 (Yepun) of ESO’s Very Large Telescope (VLT) has now been transformed into a fully adaptive telescope. After more than a decade of planning, construction and testing, the new Adaptive Optics Facility (AOF) has seen first light with the instrument MUSE, capturing amazingly sharp views of planetary nebulae and galaxies. The coupling of the AOF and MUSE forms one of the most advanced and powerful technological systems ever built for ground-based astronomy.

    ESO MUSE on the VLT

    2
    The planetary nebula NGC 6369 seen with natural seeing (left) and when the AOF is providing ground layer correction of the turbulent atmosphere (right). The AOF provides much sharper view of celestial objects and enables access to much finer and fainter structures. Credit: ESO/P. Weilbacher.

    The Adaptive Optics Facility (AOF) is a long-term project on ESO’s Very Large Telescope (VLT) to provide an adaptive optics system for the instruments on Unit Telescope 4 (UT4), the first of which is MUSE (the Multi Unit Spectroscopic Explorer) [1]. Adaptive optics works to compensate for the blurring effect of the Earth’s atmosphere, enabling MUSE to obtain much sharper images and resulting in twice the contrast previously achievable. MUSE can now study even fainter objects in the Universe.

    4
    The Adaptive Optics Facility works to remove the blurring effect of Earth’s atmosphere. When used one can see much finer details in the faint planetary nebula NGC 6563 as compared to the natural sky quality. Credit: ESO.

    “Now, even when the weather conditions are not perfect, astronomers can still get superb image quality thanks to the AOF,” explains Harald Kuntschner, AOF Project Scientist at ESO.

    Following a battery of tests on the new system, the team of astronomers and engineers were rewarded with a series of spectacular images. Astronomers were able to observe the planetary nebulae IC 4406, located in the constellation Lupus (The Wolf), and NGC 6369, located in the constellation Ophiuchus (The Serpent Bearer). The MUSE observations using the AOF showed dramatic improvements in the sharpness of the images, revealing never before seen shell structures in IC 4406 [2].

    5
    The AOF + MUSE at work. Inside the UT4 of the Very Large Telescope, part of the Adaptive Optics Facility, the four Laser Guide Stars Facility, point to the skies during the first observations using the MUSE instrument. The sharpness and dynamic range of images using the AOF equipped MUSE instrument will dramatically improve future observations. Credit: Roland Bacon.

    The AOF, which made these observations possible, is composed of many parts working together. They include the Four Laser Guide Star Facility (4LGSF) and the very thin deformable secondary mirror of UT4 [3] [4]. The 4LGSF shines four 22-watt laser beams into the sky to make sodium atoms in the upper atmosphere glow, producing spots of light on the sky that mimic stars. Sensors in the adaptive optics module GALACSI (Ground Atmospheric Layer Adaptive Corrector for Spectroscopic Imaging) use these artificial guide stars to determine the atmospheric conditions.

    GALACSI Adaptive Optics System for VLT

    6
    Inside the UT4 of the Very Large Telescope, part of the Adaptive Optics Facility, the four Laser Guide Stars Facility, point to the skies during the first observations using the MUSE instrument. The AOF system is composed of many parts working together to create sharp images of astronomical objects. Credit: Roland Bacon.

    One thousand times per second, the AOF system calculates the correction that must be applied to change the shape of the telescope’s deformable secondary mirror to compensate for atmospheric disturbances. In particular, GALACSI corrects for the turbulence in the layer of atmosphere up to one kilometre above the telescope. Depending on the conditions, atmospheric turbulence can vary with altitude, but studies have shown that the majority of atmospheric disturbance occurs in this “ground layer” of the atmosphere.

    “The AOF system is essentially equivalent to raising the VLT about 900 metres higher in the air, above the most turbulent layer of atmosphere,” explains Robin Arsenault, AOF Project Manager. “In the past, if we wanted sharper images, we would have had to find a better site or use a space telescope — but now with the AOF, we can create much better conditions right where we are, for a fraction of the cost!”

    7
    UT4 and the AOF at work. The four Laser Guide Stars Facility points to the skies during the first observations using the AOF-equipped MUSE instrument. Adaptive optics assist ground-based telescopes by compensating for the blurring effect of the Earth’s atmosphere on starlight. Credit: Roland Bacon.

    The corrections applied by the AOF rapidly and continuously improve the image quality by concentrating the light to form sharper images, allowing MUSE to resolve finer details and detect fainter stars than previously possible. GALACSI currently provides a correction over a wide field of view, but this is only the first step in bringing adaptive optics to MUSE. A second mode of GALACSI is in preparation and is expected to see first light early 2018. This narrow-field mode will correct for turbulence at any altitude, allowing observations of smaller fields of view to be made with even higher resolution.

    “Sixteen years ago, when we proposed building the revolutionary MUSE instrument, our vision was to couple it with another very advanced system, the AOF,” says Roland Bacon, project lead for MUSE. “The discovery potential of MUSE, already large, is now enhanced still further. Our dream is becoming true.”

    One of the main science goals of the system is to observe faint objects in the distant Universe with the best possible image quality, which will require exposures of many hours. Joël Vernet, ESO MUSE and GALACSI Project Scientist, comments: “In particular, we are interested in observing the smallest, faintest galaxies at the largest distances. These are galaxies in the making — still in their infancy — and are key to understanding how galaxies form.”

    Furthermore, MUSE is not the only instrument that will benefit from the AOF. In the near future, another adaptive optics system called GRAAL will come online with the existing infrared instrument HAWK-I, sharpening its view of the Universe. That will be followed later by the powerful new instrument ERIS.

    ESO Graal

    ESO HAWK-I the ESO Very Large Telescope at the Paranal Observatory in Chile, with an elevation of 2,635 metres (8,645 ft) above sea level

    ESO is driving the development of these adaptive optics systems, and the AOF is also a pathfinder for ESO’s Extremely Large Telescope,” adds Arsenault. “Working on the AOF has equipped us — scientists, engineers and industry alike — with invaluable experience and expertise that we will now use to overcome the challenges of building the ELT.”
    Notes

    [1] MUSE is an integral-field spectrograph, a powerful instrument that produces a 3D data set of a target object, where each pixel of the image corresponds to a spectrum of the light from the object. This essentially means that the instrument creates thousands of images of the object at the same time, each at a different wavelength of light, capturing a wealth of information.

    [2] IC 4406 has previously been observed with the VLT (eso9827a).

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

    [4] 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 at the artificial stars themselves and potentially affecting their observations.

    7
    ESO 338-4 is a starburst galaxy located in Sagittarius, the Archer. It is currently in the process of merging, with several smaller galaxies colliding to form the final galaxy. The new AOF+MUSE data clearly resolve several bright knots where intense star formation, induced by the merging, is occurring, as well as filaments of glowing hydrogen gas. Credit: ESO/P. Weilbacher.

    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
    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)

     
  • richardmitnick 2:24 pm on August 1, 2017 Permalink | Reply
    Tags: , , , , ESO Paranal VLT, Tau Boötis b revealed   

    From ESO via Manu: “New Way of Probing Exoplanet Atmospheres” 2012 


    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.

    ESO 50 Large

    European Southern Observatory

    27 June 2012
    Ignas Snellen
    Leiden Observatory, Leiden University
    Leiden, The Netherlands
    Tel: +31 715 275838
    Email: snellen@strw.leidenuniv.nl

    Matteo Brogi
    Leiden Observatory, Leiden University
    Leiden, The Neherlands
    Tel: +31 715 278434
    Email: brogi@strw.leidenuniv.nl

    Jayne Birkby
    Leiden Observatory, Leiden University
    Leiden, The Netherlands
    Tel: +31 715 275832
    Email: birkby@strw.leidenuniv.nl

    Richard Hook
    ESO, La Silla, Paranal, E-ELT & Survey Telescopes Press Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Remco de Kok
    Space Research Organization Netherlands (SRON)
    Utrecht, The Netherlands
    Tel: +31 88 777 5725
    Email: R.J.de.Kok@sron.nl

    Tau Boötis b revealed.

    1
    For the first time a clever new technique has allowed astronomers to study the atmosphere of an exoplanet in detail — even though it does not pass in front of its parent star. An international team has used ESO’s Very Large Telescope to directly catch the faint glow from the planet Tau Boötis b. They have studied the planet’s atmosphere and measured its orbit and mass precisely for the first time — in the process solving a 15-year old problem. Surprisingly, the team also finds that the planet’s atmosphere seems to be cooler higher up, the opposite of what was expected. The results will be published in the 28 June 2012 issue of the journal Nature.

    The planet Tau Boötis b [1] was one of the first exoplanets to be discovered back in 1996, and it is still one of the closest exoplanets known. Although its parent star is easily visible with the naked eye, the planet itself certainly is not, and up to now it could only be detected by its gravitational effects on the star. Tau Boötis b is a large “hot Jupiter” planet orbiting very close to its parent star.

    Planet transit. NASA/Ames

    Like most exoplanets, this planet does not transit the disc of its star (like the recent transit of Venus). Up to now such transits were essential to allow the study of hot Jupiter atmospheres: when a planet passes in front of its star it imprints the properties of the atmosphere onto the starlight. As no starlight shines through Tau Boötis b’s atmosphere towards us, this means the planet’s atmosphere could not be studied before.

    But now, after 15 years of attempting to study the faint glow that is emitted from hot Jupiter exoplanets, astronomers have finally succeeded in reliably probing the structure of the atmosphere of Tau Boötis b and deducing its mass accurately for the first time. The team used the CRIRES [2] instrument on the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile.

    ESO CRIRES on the VLT

    They combined high quality infrared observations (at wavelengths around 2.3 microns) [3] with a clever new trick to tease out the weak signal of the planet from the much stronger one from the parent star [4].

    Lead author of the study Matteo Brogi (Leiden Observatory, the Netherlands) explains: “Thanks to the high quality observations provided by the VLT and CRIRES we were able to study the spectrum of the system in much more detail than has been possible before. Only about 0.01% of the light we see comes from the planet, and the rest from the star, so this was not easy”.

    The majority of planets around other stars were discovered by their gravitational effects on their parent stars, which limits the information that can be gleaned about their mass: they only allow a lower limit to be calculated for a planet’s mass [5]. The new technique pioneered here is much more powerful. Seeing the planet’s light directly has allowed the astronomers to measure the angle of the planet’s orbit and hence work out its mass precisely. By tracing the changes in the planet’s motion as it orbits its star, the team has determined reliably for the first time that Tau Boötis b orbits its host star at an angle of 44 degrees and has a mass six times that of the planet Jupiter in our own Solar System.

    “The new VLT observations solve the 15-year old problem of the mass of Tau Boötis b. And the new technique also means that we can now study the atmospheres of exoplanets that don’t transit their stars, as well as measuring their masses accurately, which was impossible before”, says Ignas Snellen (Leiden Observatory, the Netherlands), co-author of the paper. “This is a big step forward.”

    As well as detecting the glow of the atmosphere and measuring Tau Boötis b’s mass, the team has probed its atmosphere and measured the amount of carbon monoxide present, as well as the temperature at different altitudes by means of a comparison between the observations and theoretical models. A surprising result from this work was that the new observations indicated an atmosphere with a temperature that falls higher up. This result is the exact opposite of the temperature inversion — an increase in temperature with height — found for other hot Jupiter exoplanets [6] [7].

    The VLT observations show that high resolution spectroscopy from ground-based telescopes is a valuable tool for a detailed analysis of non-transiting exoplanets’ atmospheres. The detection of different molecules in future will allow astronomers to learn more about the planet’s atmospheric conditions. By making measurements along the planet’s orbit, astronomers may even be able to track atmospheric changes between the planet’s morning and evening.

    “This study shows the enormous potential of current and future ground-based telescopes, such as the E-ELT. Maybe one day we may even find evidence for biological activity on Earth-like planets in this way”, concludes Ignas Snellen.
    Notes

    [1] The name of the planet, Tau Boötis b, combines the name of the star (Tau Boötis, or τ Bootis, τ is the Greek letter “tau”, not a letter “t” ) with the letter “b” indicating that this is the first planet found around this star. The designation Tau Boötis a is used for the star itself.

    [2] CRyogenic InfraRed Echelle Spectrometer

    [3] At infrared wavelengths, the parent star emits less light than in the optical regime, so this is a wavelength regime favorable for separating out the dim planet’s signal.

    [4] This method uses the velocity of the planet in orbit around its parent star to distinguish its radiation from that of the star and also from features coming from the Earth’s atmosphere. The same team of astronomers tested this technique before on a transiting planet, measuring its orbital velocity during its crossing of the stellar disc.

    [5] This is because the tilt of the orbit is normally unknown. If the planet’s orbit is tilted relative to the line of sight between Earth and the star then a more massive planet causes the same observed back and forth motion of the star as a lighter planet in a less tilted orbit and it is not possible to separate the two effects.

    [6] Thermal inversions are thought to be characterised by molecular features in emission in the spectrum, rather than in absorption, as interpreted from photometric observations of hot Jupiters with the Spitzer Space Telescope.

    NASA/Spitzer Infrared Telescope

    The exoplanet HD209458b is the best-studied example of thermal inversions in the exoplanet atmospheres.

    [7] This observation supports models in which strong ultraviolet emission associated to chromospheric activity — similar to the one exhibited by the host star of Tau Boötis b — is responsible for the inhibition of the thermal inversion.
    More information

    This research was presented in a paper The signature of orbital motion from the dayside of the planet τ Boötis b to appear in the journal Nature on 28 June 2012.

    The team is composed of Matteo Brogi (Leiden Observatory, the Netherlands), Ignas A. G. Snellen (Leiden Observatory), Remco J. de Kok (SRON, Utrecht, the Netherlands), Simon Albrecht (Massachusetts Institute of Technology, Cambridge, USA), Jayne Birkby (Leiden Observatory) and Ernst J. W. de Mooij (University of Toronto, Canada; Leiden Observatory).

    See the full article here .
    Thanks, Manu.

    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.

    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)

     
  • richardmitnick 4:37 pm on April 4, 2014 Permalink | Reply
    Tags: , , , , , ESO Paranal VLT   

    FRom ESO: “Two Galaxies for a Unique Event” 2009 


    European Southern Observatory

    4 April 2009
    Contacts

    Henri Boffin
    ESO
    Garching, Germany
    Tel: +49 89 3200 6222
    Email: hboffin@eso.org

    Valentina Rodriguez
    ESO
    Chile
    Tel: +56 2 463 3123
    Email: vrodrigu@eso.org

    To celebrate the 100 Hours of Astronomy, ESO is sharing two stunning images of unusual galaxies, both belonging to the Sculptor group of galaxies. The images, obtained at two of ESO’s observatories at La Silla and Paranal in Chile, illustrate the beauty of astronomy.

    par
    Image of the irregular galaxy NGC 55 obtained with the Wide Field Imager on the 2.2-metre MPG/ESO telescope at ESO La Silla Observatory. The galaxy is about 7.5 million light-years away and 70,000 light-years across. The image is based on data obtained through B, V, and H-alpha filters. North is up, East to the left. The field of view is 30 arcminutes wide.

    ESO Wide Field Imager 2.2m LaSilla
    WFI

    ESO 2.2 meter telescope
    2.2-metre MPG/ESO telescope

    ESO LaSilla
    LaSilla

    par
    Image of the chaotic spiral galaxy NGC 7793, observed with the FORS instrument attached to ESO’s Very Large Telescope at Paranal. The image is based on data obtained through B, V, I and H-alpha filters

    ESO FORS1
    FORS

    ESO VLT
    VLT at Paranal

    As part of the International Year of Astronomy 2009 Cornerstone project, 100 Hours of Astronomy, the ambitious “Around the World in 80 Telescopes” event is a unique live webcast over 24 hours, following night and day around the globe to some of the most advanced observatories on and off the planet. To provide a long-lasting memory of this amazing world tour, observatories worldwide are revealing wonderful, and previously unseen, astronomical images. For its part, ESO is releasing outstanding pictures of two galaxies, observed with telescopes at the La Silla and Paranal observatories.

    The first of these depicts the irregular galaxy NGC 55, a member of the prominent Sculptor group of galaxies in the southern constellation of Sculptor. The galaxy is about 70 000 light-years across, that is, a little bit smaller than our own Milky Way. NGC 55 actually resembles more our galactic neighbour, the Large Magellanic Cloud (LMC), although the LMC is seen face-on, whilst NGC 55 is edge-on.

    By studying about 20 planetary nebulae in this image, a team of astronomers found that NGC 55 is located about 7.5 million light-years away. They also found that the galaxy might be forming a bound pair with the gorgeous spiral galaxy NGC 300 . Planetary nebulae are the final blooming of Sun-like stars before their retirement as white dwarfs.

    This striking image of NGC 55, obtained with the Wide Field Imager on the 2.2-metre MPG/ESO telescope at La Silla, is dusted with a flurry of reddish nebulae, created by young, hot massive stars. Some of the more extended ones are not unlike those seen in the LMC, such as the Tarantula Nebula. The quality of the image is clearly demonstrated by the remarkable number of background galaxies seen, as well as the huge numbers of individual stars that can be counted within NGC 55.

    The second image shows another galaxy belonging to the Sculptor group. This is NGC 7793, which has a chaotic spiral structure, unlike the class of grand-design spiral galaxies to which our Milky Way belongs. The image shows how difficult it is to identify any particular spiral arm in these chaotic structures, although it is possible to guess at a general rotating pattern. NGC 7793 is located slightly further away than NGC 55, about 12.5 million light-years from us, and is about half the size of NGC 55.

    NGC 7793 was observed with one of the workhorses of the ESO Paranal Observatory, the FORS instrument, attached to the Very Large Telescope.
    Notes

    ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 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 plays also a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in the Atacama Desert region of Chile: La Silla, Paranal and Chajnantor.

    See the full article here.

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Main

    ESO, European Southern Observatory, builds and operates a suite of the world’s most advanced ground-based astronomical telescopes.


    ScienceSprings is powered by MAINGEAR computers

     
  • richardmitnick 6:06 pm on December 4, 2013 Permalink | Reply
    Tags: , , , , ESO Paranal VLT   

    From ESO: “A Galaxy Full of Surprises — NGC 3621 is bulgeless but has three central black holes” 


    European Southern Observatory

    This image, from ESO’s Very Large Telescope (VLT), shows a truly remarkable galaxy known as NGC 3621. To begin with, it is a pure-disc galaxy. Like other spirals, it has a flat disc permeated by dark lanes of material and with prominent spiral arms where young stars are forming in clusters (the blue dots seen in the image). But while most spiral galaxies have a central bulge — a large group of old stars packed in a compact, spheroidal region — NGC 3621 doesn’t. In this image, it is clear that there is simply a brightening to the centre, but no actual bulge like the one in NGC 6744 (eso1118), for example.

    ngc3621
    NGC3621 by ESO’s VLT

    las
    Another view, this one taken by the Wide Field Imager (WFI) at ESO’s La Silla Observatory

    NGC 3621 is also interesting as it is believed to have an active supermassive black hole at its centre that is engulfing matter and producing radiation. This is somewhat unusual because most of these so-called active galactic nuclei exist in galaxies with prominent bulges. In this particular case, the supermassive black hole is thought to have a relatively small mass, of around 20 000 times that of the Sun.

    Another interesting feature is that there are also thought to be two smaller black holes, with masses of a few thousand times that of the Sun, near the nucleus of the galaxy. Therefore, NGC 3621 is an extremely interesting object which, despite not having a central bulge, has a system of three black holes in its central region.

    This galaxy is located in the constellation of Hydra (The Sea Snake) and can be seen with a moderate-sized telescope. This image, taken using B, V, and I filters with the FORS1 instrument on the powerful VLT, shows striking detail in this odd object and also reveals a multitude of background galaxies. A number of bright foreground stars that belong to our own Milky Way are also visible.

    ESO VLT
    ESO’s Very Large Telescope (VLT)

    ESO LaSilla
    ESO at La Silla

    See the full article here.

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Main

    ESO, European Southern Observatory, builds and operates a suite of the world’s most advanced ground-based astronomical telescopes.


    ScienceSprings is powered by MAINGEAR computers

     
  • richardmitnick 1:04 pm on November 28, 2013 Permalink | Reply
    Tags: , , , , ESO Paranal VLT   

    From ESO: “The Topsy-Turvy Galaxy NGC 1313” 


    European Southern Observatory

    The central parts of the starburst galaxy NGC 1313.

    ngc1313

    The very active state of this galaxy is very evident from the image, showing many star formation regions. A great number of supershell nebulae, that is, cocoon of gas inflated and etched by successive bursts of star formation, are visible. The green nebulosities are regions emitting in the ionised oxygen lines and may harbour clusters with very hot stars. This colour-composite is based on images obtained with the FORS1 instrument on one of the 8.2-m Unit Telescope of ESO’s Very Large Telescope, located at Cerro Paranal. The data were obtained in the night of 16 December 2003, through different broad- (R, B, and z) and narrow-band filters (H-alpha, OI, and OIII).

    fors
    Instrument-Control-Software for FoRS

    See the full article here.

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Main

    ESO, European Southern Observatory, builds and operates a suite of the world’s most advanced ground-based astronomical telescopes.


    ScienceSprings is powered by MAINGEAR computers

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: