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  • richardmitnick 1:01 pm on June 11, 2014 Permalink | Reply
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    From ESO: “Gigantic Explosions Buried in Dust” 


    European Southern Observatory

    11 June 2014
    Contacts
    Bunyo Hatsukade
    National Astronomical Observatory of Japan
    Japan
    Tel: +81-422-34-3900 (ext. 3173)
    Email: bunyo.hatsukade@nao.ac.jp

    Masaaki Hiramatsu
    National Astronomical Observatory of Japan
    Japan
    Tel: +81-422-34-3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Lars Lindberg Christensen
    ESO education and Public Outreach Department
    Garching bei München, Germany
    Tel: +49 89 3200 6761
    Cell: +49 173 3872 621
    Email: lars@eso.org

    Observations from the Atacama Large Millimeter/submillimeter Array (ALMA) have for the first time directly mapped out the molecular gas and dust in the host galaxies of gamma-ray bursts (GRBs) — the biggest explosions in the Universe. In a complete surprise, less gas was observed than expected, and correspondingly much more dust, making some GRBs appear as “dark GRBs”. This work will appear in the journal Nature on 12 June 2014 and is the first ALMA science result on GRBs to appear. It shows ALMA’s potential to help us to better understand these objects.

    blast

    Gamma-ray bursts (GRBs) are intense bursts of extremely high energy observed in distant galaxies — the brightest explosive phenomenon in the Universe. Bursts that last more than a couple of seconds are known as long-duration gamma-ray bursts (LGRBs) and are associated with supernova explosions — powerful detonations at the ends of the lives of massive stars.

    In just a matter of seconds, a typical burst releases as much energy as the Sun will in its entire ten-billion-year lifetime. The explosion itself is often followed by a slowly fading emission, known as an afterglow, which is thought to be created by collisions between the ejected material and the surrounding gas.

    However, some gamma-ray bursts mysteriously seem to have no afterglow — they are referred to as dark bursts. One possible explanation is that clouds of dust absorb the afterglow radiation.

    In recent years, scientists have been working to better understand how GRBs form by probing their host galaxies. Astronomers expected that the massive stars that were GRB progenitors would be found in active star-forming regions in these galaxies, which would be surrounded by a large amount of molecular gas — the fuel for star formation. However, there had been no observational result to back up this theory, leaving a long-standing mystery.

    For the first time, a Japanese team of astronomers led by Bunyo Hatsukade from the National Astronomical Observatory of Japan, have used ALMA to detect the radio emission from molecular gas in two dark LGRB hosts — GRB 020819B and GRB 051022 — at about 4.3 billion and 6.9 billion light-years, respectively. Although such radio emission had never been detected in the GRB host galaxies, ALMA made it possible with its unprecedentedly high sensitivity.

    Kotaro Kohno, a professor at the University of Tokyo and a member of the research team, said, “We have been searching for molecular gas in GRB host galaxies for over ten years using various telescopes around the world. As a result of our hard work, we finally achieved a remarkable breakthrough using the power of ALMA. We are very excited with what we have achieved.”

    ALMA Array
    ALMA Array

    Another remarkable achievement made possible by the high resolution of ALMA was uncovering the distribution of molecular gas and dust in GRB host galaxies. Observations of the GRB 020819B revealed a remarkably dust-rich environment in the outskirts of the host galaxy, whereas molecular gas was found only around its centre. This is the first time that such a distribution among GRB host galaxies has been revealed.

    “We didn’t expect that GRBs would occur in such a dusty environment with a low ratio of molecular gas to dust. This indicates that the GRB occurred in an environment quite different from a typical star-forming region,” says Hatsukade. This suggests that massive stars that die as GRBs change the environment in their star-forming region before they explode.

    The research team believes that a possible explanation for the high proportion of dust compared to molecular gas at the GRB site is the difference in their reactions to ultraviolet radiation. Since the bonds between atoms which make up molecules are easily broken by ultraviolet radiation, molecular gas cannot survive in an environment exposed to the strong ultraviolet radiation produced by the hot, massive stars in its star-forming region, including the one that would eventually explode as the observed GRB. Although a similar distribution is also seen in the case of GRB 051022, this has yet to be confirmed due to the lack of resolution (as the GRB 051022 host is located further away than the GRB 020819B host). In any case, these ALMA observations support the hypothesis that it is dust that absorbs the afterglow radiation, causing the dark gamma-ray bursts.

    “The results obtained this time were beyond our expectations. We need to carry out further observations with other GRB hosts to see if this could be general environmental conditions of a GRB site. We are looking forward to future research with the improved capability of ALMA,” says Hatsukade.

    This research was presented in a paper in Nature (12 June 2014) as an article titled Two gamma-ray bursts from dusty regions with little molecular gas, by B. Hatsukade et al.

    The team is composed of B. Hatsukade (NAOJ, Tokyo, Japan), K. Ohta (Department of Astronomy, Kyoto University, Kyoto, Japan), A. Endo (Kavli Institute of NanoScience, TU Delft, The Netherlands), K. Nakanishi (NAOJ; JAO, Santiago, Chile; The Graduate University for Advanced Studies (Sokendai), Tokyo, Japan), Y. Tamura (Institute of Astronomy [IoA], University of Tokyo, Japan ), T. Hashimoto (NAOJ) and K. Kohno (IoA; Research Centre for the Early Universe, University of Tokyo, Japan).

    See the full article, with notes, here.

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  • richardmitnick 6:24 pm on January 6, 2014 Permalink | Reply
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    From ALMA at ESO: “ALMA Spots Supernova Dust Factory” 


    European Southern Observatory

    Striking new observations with the Atacama Large Millimeter/submillimeter Array (ALMA) telescope capture, for the first time, the remains of a recent supernova brimming with freshly formed dust. If enough of this dust makes the perilous transition into interstellar space, it could explain how many galaxies acquired their dusty, dusky appearance.

    dust

    Galaxies can be remarkably dusty places and supernovae are thought to be a primary source of that dust, especially in the early Universe. But direct evidence of a supernova’s dust‐making capabilities has been slim up to now, and could not account for the copious amount of dust detected in young, distant galaxies. But now observations with ALMA are changing that.

    “We have found a remarkably large dust mass concentrated in the central part of the ejecta from a relatively young and nearby supernova,” said Remy Indebetouw, an astronomer at the National Radio Astronomy Observatory (NRAO) and the University of Virginia, both in Charlottesville, USA. “This is the first time we’ve been able to really image where the dust has formed, which is important in understanding the evolution of galaxies.”

    An international team of astronomers used ALMA to observe the glowing remains of Supernova 1987A, which is in the Large Magellanic Cloud, a dwarf galaxy orbiting the Milky Way about 160 000 light‐years from Earth. SN 1987A is the closest observed supernova explosion since Johannes Kepler’s observation of a supernova inside the Milky Way in 1604.

    Astronomers predicted that as the gas cooled after the explosion, large amounts of dust would form as atoms of oxygen, carbon, and silicon bonded together in the cold central regions of the remnant. However, earlier observations of SN 1987A with infrared telescopes, made during the first 500 days after the explosion, detected only a small amount of hot dust.

    With ALMA’s unprecedented resolution and sensitivity, the research team was able to image the far more abundant cold dust, which glows brightly in millimetre and submillimetre light. The astronomers estimate that the remnant now contains about 25 percent the mass of the Sun in newly formed dust. They also found that significant amounts of carbon monoxide and silicon monoxide have formed.

    “SN 1987A is a special place since it hasn’t mixed with the surrounding environment, so what we see there was made there,” said Indebetouw. “The new ALMA results, which are the first of their kind, reveal a supernova remnant chock full of material that simply did not exist a few decades ago.”

    Supernovae, however, can both create and destroy dust grains.

    As the shockwave from the initial explosion radiated out into space, it produced bright glowing rings of material, as seen in earlier observations with the NASA/ESA Hubble Space Telescope. After hitting this envelope of gas, which was sloughed off by the progenitor red giant star as it neared the end of its life, a portion of this powerful explosion rebounded back towards the centre of the remnant. “At some point, this rebound shockwave will slam into these billowing clumps of freshly minted dust,” said Indebetouw. “It’s likely that some fraction of the dust will be blasted apart at that point. It’s hard to predict exactly how much — maybe only a little, possibly a half or two thirds.” If a good fraction survives and makes it into interstellar space, it could account for the copious dust astronomers detect in the early Universe.

    “Really early galaxies are incredibly dusty and this dust plays a major role in the evolution of galaxies,” said Mikako Matsuura of University College London, UK. “Today we know dust can be created in several ways, but in the early Universe most of it must have come from supernovae. We finally have direct evidence to support that theory.”

    See the full article, with notes, here.

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  • richardmitnick 12:08 pm on November 11, 2013 Permalink | Reply
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    From ESO: “ALMA Panoramic View with Carina Nebula” 

    ESO Photo Ambassador, Babak Tafreshi captured this panoramic view of the antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) under the clear sky over the Chajnantor Plateau, in the Chilean Andes.

    alma
    Credit: ESO/B. Tafreshi (twanight.org)

    The rosy patch prominent at the left of the image is the Carina Nebula. It lies in the constellation of Carina (The Keel), about 7500 light-years from Earth. This cloud of glowing gas and dust is the one of brightest nebulae in the sky and contains several of the brightest and most massive stars known in the Milky Way, such as Eta Carinae. For some beautiful recent images of the Carina Nebula from ESO, see eso1208, eso1145, and eso1031.

    ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    See the full ESO article here.

    ALMA Banner
    ALMA Array

    ESO ALMA

    ESO ALMA Array

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

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

    NRAO Small

    ESO 50

    NAOJ


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  • richardmitnick 1:51 pm on October 1, 2013 Permalink | Reply
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    From ESO: “Final Antenna Delivered to ALMA” 


    European Southern Observatory

    The final antenna for the Atacama Large Millimeter/submillimeter Array (ALMA) project has just been handed over to the ALMA Observatory. The 12-metre-diameter dish was manufactured by the European AEM Consortium and also marks the successful delivery of a total of 25 European antennas — the largest ESO contract so far.

    ant

    The antenna is the 66th and final antenna to be delivered to the observatory. North America has provided 25 12-metre antennas, while East Asia has delivered 16 (four 12-metre and twelve 7-metre). By the end of 2013, all 66 ultra-precise millimetre/submillimetre-wave radio antennas are expected to be working together as one telescope, in an array that will stretch for up to 16 kilometres across the Chajnantor Plateau in the Atacama Desert of northern Chile.

    See the full article here.

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  • richardmitnick 5:18 pm on August 20, 2013 Permalink | Reply
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    From ALMA: “ALMA Takes Close Look at Drama of Starbirth” 

    ESO ALMA Array
    ALMA

    20 August 2013

    From ESO

    Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have obtained a vivid close-up view of material streaming away from a newborn star. By looking at the glow coming from carbon monoxide molecules in an object called Herbig-Haro 46/47 they have discovered that its jets are even more energetic than previously thought. The very detailed new images have also revealed a previously unknown jet pointing in a totally different direction.

    starbirth

    Young stars are violent objects that eject material at speeds as high as one million kilometres per hour. When this material crashes into the surrounding gas it glows, creating a Herbig-Haro object. A spectacular example is named Herbig-Haro 46/47 and is situated about 1400 light-years from Earth in the southern constellation of Vela (The Sails). This object was the target of a study using ALMA during the Early Science phase, whilst the telescope was still under construction and well before the array was completed.

    The new images reveal fine detail in two jets, one coming towards Earth and one moving away. The receding jet was almost invisible in earlier pictures made in visible light, due to obscuration by the dust clouds surrounding the new-born star. ALMA has not only provided much sharper images than earlier facilities but also allowed astronomers to measure how fast the glowing material is moving through space.

    These new observations of Herbig-Haro 46/47 revealed that some of the ejected material had velocities much higher than had been measured before. This means the outflowing gas carries much more energy and momentum than previously thought.

    The team leader and first author of the new study, Héctor Arce (Yale University, USA) explains that ‘ALMA’s exquisite sensitivity allows the detection of previously unseen features in this source, like this very fast outflow. It also seems to be a textbook example of a simple model where the molecular outflow is generated by a wide-angle wind from the young star.’

    The observations were obtained in just five hours of ALMA observation time – even though ALMA was still under construction at the time – similar quality observations with other telescopes would have taken ten times longer.

    ‘The detail in the Herbig-Haro 46/47 images is stunning. Perhaps more stunning is the fact that, for these types of observations, we really are still in the early days. In the future ALMA will provide even better images than this in a fraction of the time,’ adds Stuartt Corder (Joint ALMA Observatory, Chile), a co-author on the new paper.

    Diego Mardones (Universidad de Chile), another co-author, emphasises that ‘this system is similar to most isolated low mass stars during their formation and birth. But it is also unusual because the outflow impacts the cloud directly on one side of the young star and escapes out of the cloud on the other. This makes it an excellent system for studying the impact of the stellar winds on the parent cloud from which the young star is formed.’”

    See the full ESO article, with notes and associated photos and videos here.

    From NRAO

    “While observing a newborn star, astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) telescope discovered twin jets of matter blasting out into space at record-breaking speed. These surprisingly forceful molecular “winds” could help refine our understanding of how stars impact their cloudy nurseries and shape their emerging stellar systems.

    During their formative years, stars both take in and blast away tremendous amounts of matter. When this ejected material collides with the surrounding gas it glows, forming what is known as a Herbig-Haro (HH) object. This give-and-take can greatly impact the way a stellar system evolves and also reshape the surrounding nebula of dust and gas from which either single or whole families of stars form.

    By studying one such stellar neighborhood, dubbed HH 46/47, the international team of astronomers uncovered high-velocity streams of carbon monoxide (CO) molecules flowing away from a star buried deep within its cloudy stellar nursery.

    ALMA’s superb sensitivity and the orientation of the star enabled the researchers to detect two jets of CO, when only one had ever been seen before. The data also revealed that this material was rushing along at 40 kilometers per second, which is 3 to 4 times faster than seen in previous CO observations.

    ‘The ALMA data reveal molecular gas close to the protostar at velocities much higher that ever observed from such an object,’ said Héctor Arce from Yale University, the principal investigator on this study. ‘This means that this rapidly fleeing gas carries much more energy and momentum than previously thought, which could significantly impact the evolution of this emerging stellar system.’

    The star, which is located 1,400 light-years away in the constellation Vela, is relatively young — on the order of a few hundred thousand years. The astronomers speculate that it is not significantly different from what our infant Sun would have looked like, though a little less massive.

    In their youth, stars bulk-up by drawing in material from a surrounding disk of dust and gas. A portion of this material, however, gets diverted and caught-up in the star’s magnetic fields causing it to be spewed out as jets from the stars’ north and south poles.

    Since there is a direct relationship between the jets and a star’s accretion disk, there is a great deal to be learned about stellar formation by simply studying the jets.

    ALMA discovered the high-velocity outflowing gas hidden within very wide-angle winds. The data also revealed that the surrounding cloud material was being pushed and accelerated by the winds. Since this is a normal, not very special protostar, the astronomers believe that the same features can be found elsewhere. If so, Arce speculates, astronomers would have to change their view on how much impact these outflows have. ‘If it has lots of energy, it can clear surrounding gas, leaving just the star and its surrounding disk of planet-forming dust and gas,’ said Arce.

    These new observations also suggest that there have been episodes of outflow followed by quieter, less active periods. This would mean that there has also been episodic accretion of material onto the star.

    Diego Mardones, a co-author on the study with the University of Chile, emphasizes that ‘this system is similar to most isolated low mass stars during their formation and birth. But it is also unusual because the outflow impacts the cloud directly on one side of the young star and escapes out of the cloud on the other. This makes it an excellent system for studying the impact of the stellar winds on the parent cloud from which the young star formed.’

    ‘The detail in the Herbig-Haro 46/47 images is stunning. Perhaps more stunning is the fact that, for these types of observations, we really are still in the early days. In the future, ALMA will provide even better images than this in a fraction of the time,’ adds Stuartt Corder with the National Radio Astronomy Observatory (NRAO), a co-author on the new paper.

    The results are published in the Astrophysical Journal.”

    See the full NRAO article here.

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

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

    NRAO Small

    ESO 50

    NAOJ


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  • richardmitnick 7:35 am on July 10, 2013 Permalink | Reply
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    From ESO: “ALMA Prenatal Scan Reveals Embryonic Monster Star” 

    10 July 2013
    Contacts
    Nicolas Peretto
    School of Physics and Astronomy, Cardiff University
    Cardiff, UK
    Tel: +44 29 208 75314
    Email: Nicolas.Peretto@astro.cf.ac.uk

    Gary Fuller
    Jodrell Bank Centre for Astrophysics, University of Manchester
    Manchester, UK
    Tel: +44 161 306 3653
    Email: G.Fuller@manchester.ac.uk

    Ana Duarte-Cabral
    Laboratoire d’Astrophysique de Bordeaux
    Bordeaux, France
    Email: Ana.Cabral@obs.u-bordeaux1.fr

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

    New observations using the Atacama Large Millimeter/submillimeter array (ALMA) have given astronomers the best view yet of a monster star in the process of forming within a dark cloud. A stellar womb with over 500 times the mass of the Sun has been found — the largest ever seen in the Milky Way — and it is still growing. The embryonic star within the cloud is hungrily feeding on material that is racing inwards. The cloud is expected to give birth to a very brilliant star with up to 100 times the mass of the Sun.

    monster

    The most massive and brightest stars in the galaxy form within cool and dark clouds but the process remains not just shrouded in dust, but also in mystery. An international team of astronomers has now used ALMA to perform a microwave prenatal scan to get a clearer look at the formation of one such monster star that is located around 11 000 light-years away, in a cloud known as the Spitzer Dark Cloud (SDC) 335.579-0.292.

    There are two theories on the formation of the most massive stars. One suggests that the parental dark cloud fragments, creating several small cores that collapse on their own and eventually form stars. The other is more dramatic: the entire cloud begins to collapse inwards, with material racing towards the cloud’s centre to form one or more massive behemoths there. A team led by Nicolas Peretto of CEA/AIM Paris-Saclay, France, and Cardiff University, UK, realised that ALMA was the perfect tool to help find out what was really happening.

    SDC335.579-0.292 was first revealed as a dramatic environment of dark, dense filaments of gas and dust through observations with NASA’s Spitzer Space Telescope and ESA’s Herschel Space Observatory. Now the team has used the unique sensitivity of ALMA to look in detail at both the amount of dust and the motion of the gas moving around within the dark cloud — and they have found a true monster.

    ‘The remarkable observations from ALMA allowed us to get the first really in-depth look at what was going on within this cloud,’ says Peretto. ‘We wanted to see how monster stars form and grow, and we certainly achieved our aim! One of the sources we have found is an absolute giant — the largest protostellar core ever spotted in the Milky Way.’

    This core — the womb of the embryonic star — has over 500 times the mass of our Sun swirling around within it. And the ALMA observations show that much more material is still flowing inwards and increasing the mass still further. This material will eventually collapse to form a young star up to 100 times as massive as our home star — a very rare beast.”

    See the full article , with notes, here.

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    THE BASIC TOOLS OF E.S.O.
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    Paranal Platform The VLT

    ESO NTT

    NTT – New Technology Telescope


    La Silla


    ALMA Atacama Large Millimeter/submillimeter Array

    i2
    The European Extremely Large Telescope
    VISTAVISTA (the Visible and Infrared Survey Telescope for Astronomy)


    Atacama Pathfinder Experiment telescope (APEX)

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  • richardmitnick 7:36 pm on June 6, 2013 Permalink | Reply
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    From ESO: “ALMA Discovers Comet Factory” 

    6 June 2013
    Contacts

    Nienke van der Marel
    Leiden Observatory
    Leiden, The Netherlands
    Tel: +31 71 527 8472
    Cell: +31 62 268 4136
    Email: nmarel@strw.leidenuniv.nl

    Ewine van Dishoeck
    Leiden Observatory
    Leiden, The Netherlands
    Tel: +31 71 527 5814
    Email: ewine@strw.leidenuniv.nl

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

    New observations of a “dust trap” around a young star solve long-standing planet formation mystery

    Astronomers using the new Atacama Large Millimeter/submillimeter Array (ALMA) have imaged a region around a young star where dust particles can grow by clumping together. This is the first time that such a dust trap has been clearly observed and modelled. It solves a long-standing mystery about how dust particles in discs grow to larger sizes so that they can eventually form comets, planets and other rocky bodies. The results are published in the journal Science on 7 June 2013.

    trap

    Astronomers now know that planets around other stars are plentiful. But they do not fully understand how they form and there are many aspects of the formation of comets, planets and other rocky bodies that remain a mystery. However, new observations exploiting the power of ALMA are now answering one of the biggest questions: how do tiny grains of dust in the disc around a young star grow bigger and bigger — to eventually become rubble, and even boulders well beyond a metre in size?

    Computer models suggest that dust grains grow when they collide and stick together. However, when these bigger grains collide again at high speed they are often smashed to pieces and sent back to square one. Even when this does not happen, the models show that the larger grains would quickly move inwards because of friction between the dust and gas and fall onto their parent star, leaving no chance that they could grow even further.

    Somehow the dust needs a safe haven where the particles can continue growing until they are big enough to survive on their own. Such “dust traps” have been proposed, but there was no observational proof of their existence up to now.

    Nienke van der Marel, a PhD student at Leiden Observatory in the Netherlands, and lead author of the article, was using ALMA along with her co-workers, to study the disc in a system called Oph-IRS. They found that the star was circled by a ring of gas with a central hole that was probably created by an unseen planet or companion star. Earlier observations using ESO’s Very Large Telescope had already shown that the small dust particles also formed a similar ring structure. But the new ALMA view of where the larger millimetre-sized dust particles were found was very different!

    ‘At first the shape of the dust in the image came as a complete surprise to us,’ says van der Marel. ‘Instead of the ring we had expected to see, we found a very clear cashew-nut shape! We had to convince ourselves that this feature was real, but the strong signal and sharpness of the ALMA observations left no doubt about the structure. Then we realised what we had found.’

    What had been discovered was a region where bigger dust grains were trapped and could grow much larger by colliding and sticking together. This was a dust trap — just what the theorists were looking for.”

    See the full article with notes here.

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    THE BASIC TOOLS OF E.S.O.
    i1
    Paranal Platform The VLT
    ESO NTT

    NTT – New Technology Telescope


    La Silla

    alma
    ALMA Atacama Large Millimeter/submillimeter Array

    i2
    The European Extremely Large Telescope
    VISTAVISTA (the Visible and Infrared Survey Telescope for Astronomy)


    Atacama Pathfinder Experiment telescope (APEX)

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


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  • richardmitnick 3:14 pm on April 29, 2013 Permalink | Reply
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    From ESO: “Gentle Giants in the Desert” 

    ESOCast 56, the machines that move ALMA antennae. This is really cool and amazing stuff. Enjoy.

    Visit ESO in Social Media-

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    THE BASIC TOOLS OF E.S.O.
    i1
    Paranal Platform The VLT
    ESO NTT

    NTT – New Technology Telescope


    La Silla

    alma
    ALMA Atacama Large Millimeter/submillimeter Array

    i2
    The European Extremely Large Telescope
    VISTAVISTA (the Visible and Infrared Survey Telescope for Astronomy)


    Atacama Pathfinder Experiment telescope (APEX)

    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 9:01 am on April 17, 2013 Permalink | Reply
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    From ESO: “ALMA Pinpoints Early Galaxies at Record Speed” 

    17 April 2013
    Contacts

    Jacqueline Hodge
    Max-Planck-Institut für Astronomie
    Heidelberg, Germany
    Tel: +49 6221 528 467
    Email: hodge@mpia.de

    Alexander Karim
    Institute for Computational Cosmology, Durham University
    Durham, United Kingdom
    Tel: +49 228 733658 (Christina Stein-Schmitz)
    Email: alexander.karim@durham.ac.uk

    Mark Swinbank
    Institute for Computational Cosmology, Durham University
    Durham, United Kingdom
    Tel: +44 191 334 3772 (Lindsay Borrero)
    Email: a.m.swinbank@durham.ac.uk

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

    A team of astronomers has used the new ALMA (Atacama Large Millimeter/submillimeter Array) telescope to pinpoint the locations of over 100 of the most fertile star-forming galaxies in the early Universe. ALMA is so powerful that, in just a few hours, it captured as many observations of these galaxies as have been made by all similar telescopes worldwide over a span of more than a decade.

    solar

    circles

    cetus

    points

    The most fertile bursts of star birth in the early Universe took place in distant galaxies containing lots of cosmic dust. These galaxies are of key importance to our understanding of galaxy formation and evolution over the history of the Universe, but the dust obscures them and makes them difficult to identify with visible-light telescopes. To pick them out, astronomers must use telescopes that observe light at longer wavelengths, around one millimetre, such as ALMA.

    ‘Astronomers have waited for data like this for over a decade. ALMA is so powerful that it has revolutionised the way that we can observe these galaxies, even though the telescope was not fully completed at the time of the observations, said Jacqueline Hodge (Max-Planck-Institut für Astronomie, Germany), lead author of the paper presenting the ALMA observations.

    The best map so far of these distant dusty galaxies was made using the ESO-operated Atacama Pathfinder Experiment telescope (APEX). It surveyed a patch of the sky about the size of the full Moon [1], and detected 126 such galaxies. But, in the APEX images, each burst of star formation appeared as a relatively fuzzy blob, which may be so broad that it covered more than one galaxy in sharper images made at other wavelengths. Without knowing exactly which of the galaxies are forming the stars, astronomers were hampered in their study of star formation in the early Universe.

    Pinpointing the correct galaxies requires sharper observations, and sharper observations require a bigger telescope. While APEX has a single 12-metre-diameter dish-shaped antenna, telescopes such as ALMA use multiple APEX-like dishes spread over wide distances. The signals from all the antennas are combined, and the effect is like that of a single, giant telescope as wide as the whole array of antennas.

    The team used ALMA to observe the galaxies from the APEX map during ALMA’s first phase of scientific observations, with the telescope still under construction. Using less than a quarter of the final complement of 66 antennas, spread over distances of up to 125 metres, ALMA needed just two minutes per galaxy to pinpoint each one within a tiny region 200 times smaller than the broad APEX blobs, and with three times the sensitivity. ALMA is so much more sensitive than other telescopes of its kind that, in just a few hours, it doubled the total number of such observations ever made.

    Not only could the team unambiguously identify which galaxies had regions of active star formation, but in up to half the cases they found that multiple star-forming galaxies had been blended into a single blob in the previous observations. ALMA’s sharp vision enabled them to distinguish the separate galaxies.

    ‘We previously thought the brightest of these galaxies were forming stars a thousand times more vigorously than our own galaxy, the Milky Way, putting them at risk of blowing themselves apart. The ALMA images revealed multiple, smaller galaxies forming stars at somewhat more reasonable rates,’ said Alexander Karim (Durham University, United Kingdom), a member of the team and lead author of a companion paper on this work.”

    [1] The observations were made in a region of the sky in the southern constellation of Fornax (The Furnace) called the Chandra Deep Field South. It has been extensively studied already by many telescopes both on the ground and in space. The new observations from ALMA extend the deep and high resolution observations of this region into the millimetre/submillimetre part of the spectrum and complement the earlier observations.

    See the full article here, with a complete list of the team’s members, videos, and other images.

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    THE BASIC TOOLS OF E.S.O.
    i1
    Paranal Platform The VLT
    ESO NTT

    NTT – New Technology Telescope


    La Silla

    alma
    ALMA Atacama Large Millimeter/submillimeter Array

    i2
    The European Extremely Large Telescope
    VISTAVISTA (the Visible and Infrared Survey Telescope for Astronomy)


    Atacama Pathfinder Experiment telescope (APEX)

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


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  • richardmitnick 3:35 pm on April 9, 2013 Permalink | Reply
    Tags: , , , , , , ESO ALMA   

    From ESO: A Trip to ALMA in the Atacama – Absolutely Worth It. Watch the Array Do Its Dance 

    A Journey to the Atacama by Nicole Gugliucci — Her part of the ALMA innauguration story

    In March 2013, a dozen journalists from around North America were guests of the National Radio Astronomy Observatory on a trip to the Atacama Desert. What was the occasion? Well, only the inauguration of the incredible Atacama Large Millimeter/Submillimeter Array in the high desert of Chile.

    ALMA will be a powerful new tool for astronomers to explore star formation, planet formation, and the birth of galaxies. We got an exclusive look at the remote observatory site with antennas at 16,500 ft elevation and an operations site at 9,000 ft. Join me on my journey to the array and back along with NRAO’s Tania Burchell, John Stoke, and Charles Blue and the Planetary Society’s Mat Kaplan.

    Enjoy:

    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube
    THE BASIC TOOLS OF E.S.O.
    i1
    Paranal Platform The VLT
    ESO NTT

    NTT – New Technology Telescope


    La Silla

    alma
    ALMA Atacama Large Millimeter/submillimeter Array

    i2
    The European Extremely Large Telescope
    VISTAVISTA (the Visible and Infrared Survey Telescope for Astronomy)


    Atacama Pathfinder Experiment telescope (APEX)

    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

     
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