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  • richardmitnick 10:33 am on September 8, 2021 Permalink | Reply
    Tags: "ALMA Goes to New (Wave) Lengths", "First light" is the ultimate test that design; fabrication; and assembly are all perfect., "First light" marks a major breakthrough as it is the first time that an astronomical signal (light) goes through the entire telescope., ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), , , , During the test observations the new receivers successfully received signals from various objects from near to far., , , So far eight out of ten receivers have been mounted on the antennas covering altogether the window between 0.3 and 3.6 millimeters., The Band 1 receiver once installed on all 66 ALMA antennas will break new ground in various science areas., The new receiver will allow astronomers to peer out at the distant redshifted Universe further than any other receiver on ALMA.   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : “ALMA Goes to New (Wave) Lengths” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    8 September, 2021

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    1
    Band-1 cold cartridge assemblies at the Band-1 Integration and Verification Laboratory at Aeronautical Systems Research Division TAF Labs (TW). Credits: ASIAA/Yuh-Jing Hwang and ASRD.

    2
    Band-1 warm cartridge assemblies integrated and tested at the Band-1 Integration and Verification Laboratory at ASRD in Taiwan. Credits: ASIAA/Yuh-Jing Hwang and ASRD.

    3
    Band-1 receiver with cold cartridge assembly (front), lens (middle) and warm cartridge assembly (right) ready for installation at the ALMA OSF in Chile. Credit: G.Siringo – ALMA (ESO/NAOJ/NRAO.

    5
    First Band-1 receiver installed into cryostat (blue) at the ALMA OSF in Chile for noise measurement. The center white circular structure is the lens for the Band-1 receiver with the cold cartridge assembly mounted behind it. Credit: Yuh-Jing Hwang – ASIAA

    The Atacama Large Millimeter/submillimeter Array (ALMA) achieved first light with new Band 1 receivers, setting a new record for the most extended wavelengths capabilities with its radio antennas. This achievement opens a window on the Universe previously inaccessible at the telescope, thanks to an international team of engineers.

    ALMA observes the Universe over a wide range of radio wavelengths within the millimeter and submillimeter section of the electromagnetic spectrum with the help of specialized receivers. Each one is sensitive to a particular “band” of wavelengths. So far eight out of ten receivers have been mounted on the antennas covering altogether the window between 0.3 and 3.6 millimeters.

    The international team worked hard to integrate the receiver in the ALMA telescope and perform test observations under challenging conditions. “One of the most challenging issues has been the remote coordination of the activities of all the people involved,” says Giorgio Siringo, ALMA Senior Engineer. “That have been carried out from different continents during the pandemic emergency.”

    For any new receiver, the successful ‘first light’ marks a major breakthrough as it is the first time that an astronomical signal (light) goes through the entire telescope, from the antenna that is collecting the light, through the receiver with all the backend electronics, to a computer screen at the end displaying the result. It is the ultimate test that design; fabrication; and assembly are all perfect. After around 10 years of hard and meticulous work, the Band 1 receiver successfully achieved first light with successful observations of the edge of the Moon on 14 August 2021, followed by the first successful interferometry test observations with two antennas with Band 1 receivers on 17 August, and the acquisition of the first radio spectrum on 27 August. During the test observations the new receivers successfully received signals from various objects from near to far, including planets (Venus, and Mars), evolved stars and molecular clouds (Orion KL and VY Canis Majoris) in our Galaxy, and extra-galactic distant quasars (3C 279), and the team confirmed the receiver’s performance.

    The Band 1 receiver once installed on all 66 ALMA antennas will break new ground in various science areas. The new receiver will allow astronomers to peer out at the distant redshifted Universe further than any other receiver on ALMA. Band 1 is also much anticipated to make the next breakthrough discoveries in the study of planet formation. The production of receivers for all ALMA antennas is currently being completed in Taiwan, aiming to offer this new band for open-use observations from Cycle 10, starting in 2023.

    “It will enable the detection of centimeter-sized dust grains and small pebbles in regions where planets can form. With this we can study the growth of dust grains and eventually understand how planets form out of interstellar dust”, says Hsi-Wei Yen, the Band 1 project scientist at Taiwan’s Academia Sinica Institute of Astronomy and Astrophysics (ASIAA).

    The development of the ALMA Band 1 is led by Academia Sinica Institute of Astronomy and Astrophysics(TW), supported by an international team comprising the National Astronomical Observatory of Japan (NAOJ), The University of Chile [Universidad de Chile](CL), the National Radio Astronomy Observatory (NRAO), The Herzberg Institute of Astrophysics (CA) and the The National Chung-Shan Institute of Science and Technology [ 國家中山科學研究院] (TW). Since the beginning,The University of Chile [Universidad de Chile](CL) has been involved in the project, helping to develop and produce optical elements such as the lenses and horn antennas for the Band 1 receivers.

    Recently, the ALMA board signed a contract to develop the last missing set of ALMA receivers (Band 2), which a consortium of European institutions will lead.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL) , 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 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

     
  • richardmitnick 8:33 pm on July 10, 2021 Permalink | Reply
    Tags: , ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), , , , , , Osaka Prefecture University (JP),   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : “New Radio Receiver Opens Wider Window to Radio Universe” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    2021.07.08

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Valeria Foncea
    Education and Public Outreach Officer
    Joint ALMA Observatory Santiago – Chile
    Phone: +56 2 2467 6258
    Cell phone: +56 9 7587 1963
    Email: valeria.foncea@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    Researchers have used the latest wireless technology to develop a new radio receiver for astronomy. The receiver is capable of capturing radio waves at frequencies over a range several times wider than conventional ones, and can detect radio waves emitted by many types of molecules in space at once. This is expected to enable significant progresses in the study of the evolution of the Universe and the mechanisms of star and planet formation.

    Interstellar molecular clouds of gas and dust provide the material for stars and planets. Each type of molecule emits radio waves at characteristic frequencies and astronomers have detected emissions from various molecules over a wide range of frequencies. By observing these radio waves, we can learn about the physical properties and chemical composition of interstellar molecular clouds. This has been the motivation driving the development of a wideband receiving system.

    In general, the range of radio frequencies that can be observed simultaneously by a radio telescope is very limited. This is due to the characteristics of the components that make up a radio receiver. In this new research, the team of researchers in Osaka Prefecture University (JP) and the National Astronomical Observatory of Japan has widened the bandwidth of various components, such as the horn that brings radio waves into the receiver, the waveguide (metal tube) circuit that propagates the radio waves, and the radio frequency converter. By combining these components into a receiver system, the team has achieved a range of simultaneously detectable frequencies several times larger than before. Furthermore, this receiver system was mounted on the OPU 1.85-m radio telescope in NAOJ’s Nobeyama Radio Observatory, and succeeded in capturing radio waves from actual celestial objects. This shows that the results of this research are extremely useful in actual astronomical observations.

    2
    Newly developed radio receiving system. The radio waves collected by the antenna are directed to the receiver through the horn at the lower left of the photo and follow the path indicated by the arrow to be output.
    Credit: Osaka Prefecture University.

    3
    Six radio emission lines from isotopologues of carbon monoxide observed simultaneously by the newly developed broadband receiver. The observed object is a region called “Orion KL” in the Orion Nebula. Credit: Osaka Prefecture University/NAOJ.

    4
    Distribution of CO isotopologues in the Orion molecular cloud observed simultaneously with the newly developed broadband receiver. The C^18 O (J=3-2) emission line was also observed, but is not shown because the radio signal strength was too weak to obtain an image.
    Credit: Osaka Prefecture University/NAOJ

    “It was a very emotional moment for me to share the joy of receiving radio waves from the Orion Nebula for the first time with the members of the team, using the receiver we had built,” comments Yasumasa Yamasaki, an OPU graduate student and the lead author of the paper describing the development of the wideband receiver components. “I feel that this achievement was made possible by the cooperation of many people involved in the project.”

    When compared to the receivers currently used in the Atacama Large Millimeter/submillimeter Array (ALMA), the breadth of frequencies that can be simultaneously observed with the new receivers is striking. To cover the radio frequencies between 211 and 373 GHz, ALMA uses two receivers, Band 6 and 7, but can use only one of them at a given time. In addition, ALMA receivers can observe two strips of frequency ranges with widths of 5.5 and 4 GHz using the Band 6 and 7 receivers, respectively. In contrast, the new wideband receiver can cover all the frequencies with a single unit. In addition, especially in the higher frequency band, the receiver can detect radio waves in a frequency range of 17 GHz at a time.

    5
    Schematic diagram of the observable frequency bands of the newly developed broadband receiver system (top) and the ALMA Band 6 and Band 7 receivers (bottom). The darker areas indicate the frequency bands that can be observed simultaneously. The ALMA Band 6 receiver can observe two 5.5 GHz bands, and the Band 7 receiver can observe two 4 GHz bands at the same time. The newly developed wideband receiver system is capable of observing two 4-GHz bands and one 17-GHz band; thus six carbon monoxide emission lines can be observed simultaneously.
    Credit: Osaka Prefecture University/NAOJ.

    “It was a very valuable experience for me to be involved in the development of this broadband receiver from the beginning to successful observation,” says Sho Masui, a graduate student at OPU and the lead author of the research paper reporting the development of the receiver and the test observations. “Based on these experiences, I would like to continue to devote further efforts to the advancement of astronomy through instrument development.”

    This wideband technology has made it possible to observe the interstellar molecular clouds along the Milky Way more efficiently using the 1.85-m radio telescope. In addition, widening the receiver bandwidth is listed as one of the high priority items in the ALMA Development Roadmap which aims to further improve the performance of ALMA. This achievement is expected to be applied to ALMA and other large radio telescopes, and to make a significant contribution to enhance our understanding of the evolution of the Universe.

    Additional Information

    These research results are presented in the following two papers published in the Publications of the Astronomical Society of Japan.
    – S. Masui et al. “Development of a new wideband heterodyne receiver system for the Osaka 1.85 m mm–submm telescope: Receiver development and the first light of simultaneous observations in 230 GHz and 345 GHz bands with an SIS-mixer with 4–21 GHz IF output”
    – Y. Yamasaki et al. “Development of a new wideband heterodyne receiver system for the Osaka 1.85 m mm–submm telescope: Corrugated horn and optics covering the 210–375 GHz band”

    This research was supported by MEXT/JSPS KAKENHI (JP18H05440, JP20J23670, JP15K05025, and JP26247026).

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL), 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 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

     
  • richardmitnick 9:44 am on June 17, 2021 Permalink | Reply
    Tags: "ALMA Observes Deep into Chaotic Planetary Nursery", , ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), Astronomers have been studying protoplanetary discs for decades., , , , , , Something not observed in a protoplanetary disk before: two large-scale spiral arms., The massive protoplanetary disk of Elias 2-27 a young star 378 light-years away in the Ophiuchus constellation.   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : Women in STEM-Teresa Paneque Carreño; Laura Perez;Cassandra Hall; Benedetta Veronesi “ALMA Observes Deep into Chaotic Planetary Nursery” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    17 June, 2021

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    Planet formation is still a mystery. Astronomers have been studying protoplanetary discs for decades, trying to solve the details of planetary genesis. Thanks to ALMA, a team of scientists, for the first time, dug deep into the spiral structures of the massive protoplanetary disk of Elias 2-27, a young star 378 light-years away in the Ophiuchus constellation. The research team thinks that gravitational instabilities are the origin of the spirals rather than the interaction with a planet or accompanying star. The results of this study appeared in The Astrophysical Journal today.

    1
    Multiple molecular tracers helped scientists to better understand the gases present in the disk surrounding Elias 2-27. Visible in this composite are the 0.87mm dust continuum data (blue), C18O emission (yellow), and 13CO emission (red). Credit: Teresa Paneque-Carreño/ Bill Saxton, NRAO/Associated Universities Inc (US)/National Science Foundation (US).

    2
    Using gas velocity data, scientists observing Elias 2-27 were able to directly measure the mass of the young star’s protoplanetary disk and also trace dynamical perturbations in the star system. Visible in this animation are the dust continuum 0.87mm emission data (blue), along with emissions from gases C18O (yellow) and 13CO (red). Credit: Teresa Paneque-Carreño/ Bill Saxton, NRAO/AUI/NSF.

    3
    Using gas velocity data, scientists observing Elias 2-27 were able to directly measure the mass of the young star’s protoplanetary disk and also trace dynamical perturbations in the star system. Visible in this paneled composite are the dust continuum 0.87mm emission data (blue), along with emissions from gases C18O (yellow) and 13CO (red). Credit: Teresa Paneque-Carreño/ Bill Saxton, NRAO/AUI/NSF.

    4
    Elias 2-27 is a young star located just 378 light-years from Earth. The star is host to a massive protoplanetary disk of gas and dust, one of the key elements to planet formation. In this graphic illustration, dust is distributed along a spiral-shaped morphology first discovered in Elias 2-27 in 2016. The larger dust grains are found along the spiral arms while the smaller dust grains are distributed all around the protoplanetary disk. Asymmetric inflows of gas were also detected during the study, indicating that there may still be material infalling into the disk. Scientists believe that Elias 2-27 may eventually evolve into a planetary system, with gravitational instabilities causing the formation of giant planets. Because this process takes millions of years to occur, scientists can only observe the beginning stages. Credit: Bill Saxton, NRAO/AUI/NSF.

    Disks of gas and dust surround newly formed young stars. They are called protoplanetary disks, and astronomers expect planets to develop in them within the first 10 million years of the stars’ lives.

    “How exactly planets form is one of the main questions in our field. However, there are some key mechanisms that we believe can drive the process,” explains Teresa Paneque Carreño, a former Astronomy student from University of Chile [Universidad de Chile] (CL) who is now doing her Ph.D. at European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL) in Garching and Principal Investigator of this study. “One of these mechanisms is gravitational instabilities, a process that occurs when the disk is massive enough that its gravity becomes relevant in the way particles interact between them.” Gravitational instabilities can cause the disk to fragment in small clumps, which could become giant planets very fast.

    Elias 2-27’s unique characteristics have made it popular with ALMA scientists for more than half a decade. A team led by Laura Perez from Universidad de Chile and co-author of this new investigation discovered, also using ALMA, the spirals in Elias 2-27’s disk back in 2016 [Science]. But they were unable to determine what generated the gravitational instabilities. Further observations in multiple ALMA bands and gas tracers were needed to explore the structure of the spirals in both gas and dust.

    “We discovered in 2016 that the Elias 2-27 disk had a different structure from other already studied systems. Something not observed in a protoplanetary disk before: two large-scale spiral arms. The origin of these structures remained a mystery, and therefore we needed further observations,” explains Perez. “And so, together with collaborators, we put a proposal in ALMA to simultaneously explore both the gas and dust emission from this system. This new study became the focus of Teresa’s MSc thesis at Universidad de Chile”.

    Cassandra Hall, Assistant Professor of Computational Astrophysics at the University of Georgia (US) and a co-author on the research, added that the confirmation of both vertical asymmetry and velocity perturbations—the first large-scale perturbations linked to spiral structure in a protoplanetary disk—could have significant implications for planet formation theory. “This could be a ‘smoking gun’ of gravitational instability, which may accelerate some of the earliest stages of planet formation. We first predicted this signature in 2020 [The Astrophysical Journal], and from a computational astrophysics point of view, it’s exciting to be right.”

    Paneque-Carreño added that while the new research has confirmed some theories, it has also raised further questions. “While gravitational instabilities can now be confirmed to explain the spiral structures in the dust continuum surrounding the star, there is also an inner gap, or missing material in the disk, for which we do not have a clear explanation.”

    “The high-angular resolution images obtained with ALMA at multiple wavelengths was key to studying the disk morphology and dust properties,” explains John Carpenter, ALMA Observatory Scientist and co-author of this research. “The spatial location of the different sized particles allows us to understand the dust growth processes and infer the origin of the spiral morphology.”

    Additionally, ALMA’s high sensitivity allowed the team to study the kinematic perturbations and the dynamical processes traced by molecular emission. Using two molecules as tracers (13CO and C18O), they found that the disk was highly perturbed and surrounded by large-scale gas emissions produced by material beyond the extent of the main dust and gas disk.

    “We were surprised to find vertical perturbations in the gas of the disk. This has not been observed in this kind of source before,” says Paneque Carreño. “The perturbations are too large to be explained by a companion. The asymmetric vertical structure of the disk is probably related to ongoing infall of material, showing how chaotic planet formation sites are.”

    One of the barriers to understanding planet formation was the lack of direct mass measurement of planet-forming disks, a problem addressed in the new research. The high sensitivity of ALMA allowed the team to more closely study the dynamical processes, density, and even the mass of the disk. “Previous mass measurements of protoplanetary disks were indirect, based only on dust or rare isotopologues. With this new study, we are now sensitive to the entire mass of the disk,” said Benedetta Veronesi—a graduate student at the University of Milan [Università degli Studi di Milano Statale] (IT) and postdoctoral researcher at Lyon Higher Normal School [École normale supérieure de Lyon] (FR), and lead author on a second paper. “This finding lays the foundation for the development of a method to measure disk mass that will allow us to break down one of the biggest and most pressing barriers in the field of planet formation. Knowing the amount of mass present in planet-forming disks allows us to determine the amount of material available for the formation of planetary systems and to understand better the process by which they form.”

    Although the team has answered many critical questions about the role of gravitational instability and disk mass in planet formation, the work is not done yet. “Studying how planets form is difficult because it takes millions of years to form planets. This is a very short time-scale for stars, which live thousands of millions of years, but a very long process for us,” said Paneque-Carreño. “What we can do is observe young stars, with disks of gas and dust around them, and try to explain why these disks of material look the way they do. It’s like looking at a crime scene and trying to guess what happened. Our observational analysis paired with future in-depth analysis of Elias 2-27 will allow us to characterize exactly how gravitational instabilities act in planet-forming disks and gain more insight into how planets are formed.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL) , 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 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

     
  • richardmitnick 3:38 pm on May 20, 2021 Permalink | Reply
    Tags: "ALMA Discover Most Ancient Spiral Galaxy", ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), , , , ,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : “ALMA Discover Most Ancient Spiral Galaxy” 

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    20 May, 2021

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Amy C. Oliver
    Public Information & News Manager
    National Radio Astronomical Observatory (NRAO), USA
    Phone: +1 434 242 9584
    Email: aoliver@nrao.edu

    1
    ALMA image of the galaxy BRI 1335-0417 at 12.4 billion years ago. ALMA detected emissions from carbon ions in the galaxy. Spiral arms are visible on both sides of the compact, bright area in the galaxy center. Credit: ALMA (ESO/NAOJ/NRAO), T. Tsukui & S. Iguchi


    Formation of a Spiral Galaxy (ver. 3)

    Analyzing data obtained with the Atacama Large Millimeter/submillimeter Array (ALMA), researchers found a galaxy with a spiral morphology in the Universe, only 1.4 billion years after the Big Bang. This is the most ancient galaxy of its kind ever observed. The discovery of a galaxy with a spiral structure at such an early stage is an essential clue to solve the classic questions of astronomy: “How and when did spiral galaxies form?”

    “I was excited because I had never seen such clear evidence of a rotating disk, spiral structure, and centralized mass structure in a distant galaxy in any previous literature,” says Takafumi Tsukui, a graduate student at SOKENDAI and the lead author of the research paper published in the journal Science. “The quality of the ALMA data was so good that I was able to see so much detail that I thought it was a nearby galaxy.”

    The Milky Way Galaxy, where we live, is a spiral galaxy. Spiral galaxies are fundamental objects in the Universe, accounting for as much as 70% of the total number of galaxies. However, studies have shown that the proportion of spiral galaxies declines rapidly as we look back through the history of the Universe. So, when were the spiral galaxies formed?

    Tsukui and his supervisor Satoru Iguchi, a professor at SOKENDAI and the National Astronomical Observatory of Japan [国立天文台](JP), noticed a galaxy called BRI 1335-0417 in the ALMA Science Archive. The galaxy existed 12.4 billion years ago and contained a large amount of dust which obscures the starlight, making it difficult to study this galaxy in detail with visible light. On the other hand, ALMA can detect radio emissions from carbon ions in the galaxy, enabling astronomers to investigate what is going on in the galaxy.

    The researchers found a spiral structure extending about 15,000 light-years from the center of the galaxy: one-third of the size of the Milky Way. The estimated total mass of stars and interstellar matter in BRI 1335-0417 is roughly identical to that of the Milky Way.

    “As BRI 1335-0417 is a very distant object, we might not be able to see the true edge of the galaxy in this observation,” comments Tsukui. “For a galaxy that existed in the early Universe, BRI 1335-0417 was giant.”

    Then the question becomes, how was this distinct spiral structure formed in only 1.4 billion years after the Big Bang? The researchers considered multiple possible causes and suggested that it could be due to an interaction with a small galaxy. BRI 1335-0417 is actively forming stars, and the researchers found that the gas in the outer part of the galaxy is gravitationally unstable, which is conducive to star formation. This situation is likely to occur when a large amount of gas is supplied from the outside, possibly due to collisions with smaller galaxies.

    The fate of BRI 1335-0417 is also shrouded in mystery. Galaxies that contain large amounts of dust and actively produce stars in the ancient Universe are thought to be the ancestors of the giant elliptical galaxies in the present Universe. In that case, BRI 1335-0417 changes its shape from a disk galaxy to an elliptical one in the future. Or, contrary to the conventional view, the galaxy may remain a spiral galaxy for a long time. BRI 1335-0417 will play an essential role in studying the evolution of galaxy shape evolution over the long history of the Universe.

    “Our Solar System lodges in one of the Milky Way spiral arms,” explains Iguchi. “Tracing the roots of spiral structure will provide us with clues as to the environment in which the Solar System was born. I hope that this research will further advance our understanding of the formation history of galaxies.”

    Additional Information

    These research results are presented in Science on Thursday, 20 May 2021.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

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

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  • richardmitnick 12:21 pm on March 24, 2021 Permalink | Reply
    Tags: "Astronomers image magnetic fields at the edge of M87’s black hole[Messier 87*]", ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), , , , , , ,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “Astronomers image magnetic fields at the edge of M87’s black hole[Messier 87*]” 

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    Dave Finley
    Public Information Officer
    Karl G. Jansky Very Large Array (VLA)
    Phone: 1 575.835-7302
    Email: dfinley@nrao.edu

    Event Horizon Telescope Array


    Arizona Radio Observatory.

    European Southern Observatory(EU)/MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) ESO’s Atacama Pathfinder Experiment(CL) high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft).


    ESO APEX.

    Combined Array for Research in Millimeter-wave Astronomy (CARMA Array for Research in Millimeter-wave Astronomy(US)), in the Inyo Mountains to the east of the California Institute of Technology Owens Valley Radio Observatory(US), at a site called Cedar Flat, Altitude 1,222 m (4,009 ft), relocated to Owens Valley Radio Observatory, Altitude 1,222 m (4,009 ft).


    CARMA.

    National Astronomy Observatory of Japan(JP) Atacama Submillimeter Telescope Experiment (ASTE) deployed to its site on Pampa La Bola, near Cerro Chajnantor and the Llano de Chajnantor, Observatory in northern Chile, Altitude 4,800 m (15,700 ft).


    NAOJ Atacama Submillimeter Telescope Experiment (ASTE).

    California Institute of Technology Submillimeter Observatory(US) on MaunaKea, Hawaii, USA, Altitude 4,205 m (13,796 ft).


    Caltech Submillimeter Observatory.


    Greenland Telescope.

    Institute of Radio Astronomy [Institut de Radioastronomie Millimétrique](ES) 30m Radio telescope, on Pico Veleta in the Spanish Sierra Nevada, Altitude 2,850 m (9,350 ft).


    (IRAM) 30m.

    IRAM-Institut de Radioastronomie Millimetrique (FR) NOEMA Interferometer in the French Alps on the wide and isolated Plateau de Bure at an elevation of 2550 meters, the telescope currently consists of ten antennas, each 15 meters in diameter.interferometer, Located in the French Alpes on the wide and isolated Plateau de Bure at an elevation of 2550 meters.


    IRAM NOEMA, France.


    James Clerk Maxwell Telescope.

    The University of Massachusetts Amherst and Mexico’s Instituto Nacional de Astrofísica, Óptica y Electrónica
    LMT – Large Millimeter Telescope Alfonso Serrano(MX), Mexico, at an altitude of 4850 meters on top of the Sierra Negra.


    Large Millimeter Telescope Alfonso Serrano.


    ESO/NRAO/NAOJ ALMA Array.

    South Pole Telescope SPTPOL. The SPT collaboration is made up of over a dozen (mostly North American) institutions, including the University of Chicago; the University of California, Berkeley; Case Western Reserve University; Harvard/Smithsonian Astrophysical Observatory; the University of Colorado, Boulder; McGill(CA) University, The University of Illinois, Urbana-Champaign: University of California, Davis; Ludwig Maximilians Universität München(DE); Argonne National Laboratory; and the National Institute for Standards and Technology. It is funded by the National Science Foundation(US).

    Future Array/Telescopes

    California Institute of Technology Owens Valley Radio Observatory(US), located near Big Pine, California (US) in Owens Valley, Altitude1,222 m (4,009 ft).


    Caltech Owens Valley Radio Observatory.

    The Event Horizon Telescope (EHT) collaboration, which produced the first-ever image of a black hole, has today revealed a new view of the massive object at the center of the Messier 87 (M87) galaxy: how it looks in polarised light. With this data, astronomers measured polarization, a signature of magnetic fields, for the first time this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, can launch energetic jets from its core.

    “We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy,” says Monika Mościbrodzka, Coordinator of the EHT Polarimetry Working Group and Assistant Professor at Radboud University [Radboud Universiteit](NL).

    On April 10, 2019, scientists released the first-ever image of a black hole, revealing a bright ring-like structure with a dark central region — the black hole’s shadow. Since then, the EHT collaboration has delved deeper into the supermassive object’s data at the heart of the M87 galaxy collected in 2017. They have discovered that a significant fraction of the light around the M87 black hole is polarized.

    “This work is a major milestone: the polarisation of light carries information that allows us to understand better the physics behind the image we saw in April 2019, which was not possible before,” explains Iván Martí-Vidal, also Coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the University of Valencia [Universitat de València](ES). He adds that “unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analyzing the data.“

    Light becomes polarized when it goes through certain filters, like the lenses of polarized sunglasses, or when it is emitted in hot regions of space where magnetic fields are present. In the same way that polarized sunglasses help us see better by reducing reflections and glare from bright surfaces, astronomers can sharpen their view of the region around the black hole by looking at how the light originating from it is polarized. Specifically, polarization allows astronomers to map the magnetic field lines present at the inner edge of the black hole.

    “The newly published polarised images are key to understanding how the magnetic field allows the black hole to ‘eat’ matter and launch powerful jets,” says EHT collaboration member Andrew Chael, a NASA Hubble Fellow at the Princeton University Center For Theoretical Science(US) and the Princeton Gravity Initiative(US).

    The bright jets of energy and matter that emerge from M87’s core and extend at least 5000 light-years from its center are one of the galaxy’s most mysterious and energetic features. Most matter lying close to the edge of a black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space in the form of jets.

    Astronomers have relied on different models of how matter behaves near the black hole to understand this process better. But they still don’t know precisely how jets larger than the galaxy are launched from its central region, comparable in size to the Solar System, nor how exactly matter falls into the black hole. With the new EHT image of the black hole and its shadow in polarised light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening.

    The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetized gas can explain what they see at the event horizon.

    “The observations suggest that the magnetic fields at the black hole’s edge are strong enough to push back on the hot gas and help it resist gravity’s pull. Only the gas that slips through the field can spiral inwards to the event horizon,” explains Jason Dexter, Assistant Professor at the University of Colorado Boulder(US), and Coordinator of the EHT Theory Working Group.

    To observe the heart of the M87 galaxy, the collaboration linked eight telescopes worldwide — including the northern Chile-based ALMA-Atacama Large Millimeter/submillimeter Array(CL) — to create a virtual Earth-sized telescope, the Event Horizon Telescope. The impressive resolution obtained with the EHT is equivalent to that needed to measure a credit card’s length on the Moon’s surface.

    “With ALMA [above] and APEX[above], which through their southern location enhance the image quality by adding geographical spread to the EHT network, European scientists were able to play a central role in the research,” says Ciska Kemper, European ALMA Programme Scientist at European Southern Observatory(EU). “With its 66 antennas, ALMA dominates the overall signal collection in polarised light, while APEX has been essential for the calibration of the image.”

    “ALMA data were also crucial to calibrate, image and interpret the EHT observations, providing tight constraints on the theoretical models that explain how matter behaves near the black hole event horizon,” adds Ciriaco Goddi, a scientist at Radboud University and Leiden Observatory(NL), who led an accompanying study that relied only on ALMA observations.

    “ALMA plays a central role in the entire process: it is centrally located to tie the EHT array together, and it is also the most sensitive telescope in the array, so it is crucial to making the most of the EHT data,” said Geoff Crew, Haystack Research Scientist. “In addition, the years of work on the ALMA polarimetry analysis has delivered far more than we imagined.”

    The EHT setup allowed the team to directly observe the black hole shadow and the ring of light around it, with the new polarised-light image clearly showing that the ring is magnetized. The results are published today in two separate papers in The Astrophysical Journal Letters by the EHT collaboration. The research involved over 300 researchers from multiple organizations and universities worldwide.

    “The EHT is making rapid advancements, with technological upgrades being done to the network and new observatories being added. We expect future EHT observations to reveal more accurately the magnetic field structure around the black hole and to tell us more about the physics of the hot gas in this region,” concludes EHT collaboration member Jongho Park, an East Asian Core Observatories Association Fellow at the Academia Sinica Institute of Astronomy and Astrophysics in Taipei.
    Additional Information

    This research was presented in two papers by the EHT collaboration published today in The Astrophysical Journal Letters: First M87 Event Horizon Telescope Results VII: Polarization of the Ring and First M87 Event Horizon Telescope Results VIII: Magnetic Field Structure Near The Event Horizon. Accompanying research is presented in the paper Polarimetric properties of Event Horizon Telescope targets from ALMA by Goddi, Martí-Vidal, Messias, and the EHT collaboration, which has been accepted for publication in The Astrophysical Journal Letters.

    The EHT collaboration involves more than 300 researchers from Africa, Asia, Europe, North and South America. The international collaboration is working to capture the most detailed black hole images ever obtained by creating a virtual Earth-sized telescope. Supported by considerable international investment, the EHT links existing telescopes using novel systems — creating a fundamentally new instrument with the highest angular resolving power that has yet been achieved.

    The individual telescopes involved are: ALMA, APEX, the Institut de Radioastronomie Millimetrique (IRAM) 30-meter Telescope, the IRAM NOEMA Observatory, the James Clerk Maxwell Telescope (JCMT), the Large Millimeter Telescope (LMT), the Submillimeter Array (SMA), the Submillimeter Telescope (SMT), the South Pole Telescope (SPT), the Kitt Peak Telescope, and the Greenland Telescope (GLT) [All above].

    The EHT consortium consists of 13 stakeholder institutes: the Academia Sinica Institute of Astronomy and Astrophysics(TW), the University of Arizona(US), the University of Chicago(US), the East Asian Observatory – Hilo, Hawaii(US), Goethe-Universitaet Frankfurt(DE), Institute of Radio Astronomy [Institut de Radioastronomie Millimétrique](ES), LMT – Large Millimeter Telescope Alfonso Serrano(MX), MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE), Massachusettes Institute of Technology-Haystack Observatory(US), National Astronomical Observatory of Japan [国立天文台](JP), Perimeter Institute for Theoretical Physics(CA), Radboud University [Radboud Universiteit](NL) and the Harvard Smithsonian Center for Astrophysics(US).

    1
    The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole released in 2019, has today a new view of the massive object at the centre of the Messier 87 galaxy [Messier 87*]: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. This image shows the polarised view of the black hole in Messier 87 [Messier 87*]. The lines mark the orientation of polarisation, which is related to the magnetic field around the shadow of the black hole. Credit: Event Horizon Telescope Collaboration.

    2
    This composite image shows three views of the central region of the Messier 87 galaxy in polarised light. The galaxy has a supermassive black hole at its centre [Messier 87*] and is famous for its jets, that extend far beyond the galaxy. One of the polarised-light images, obtained with ALMA shows part of the jet in polarised light. This image captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view covers a region about one light year in size and was obtained with the National Radio Astronomy Observatory’s Very Long Baseline Array(US) in the US.

    The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope. This allows astronomers to see very close to the supermassive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged.The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the Messier 87 galaxy along its powerful jets (as probed with ALMA on scales of thousand of light-years). The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual images. Credit: EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal.

    3
    This composite image shows three views of the central region of the Messier 87 galaxy in polarised light and one view, in the visible wavelength, taken with the Hubble Space Telescope.

    The galaxy has a supermassive black hole at its centre [Messier 87*] and is famous for its jets, that extend far beyond the galaxy. The Hubble image at the top captures a part of the jet some 6000 light years in size. One of the polarised-light images, obtained with obtained with ALMA shows part of the jet in polarised light. This image captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The other polarised light images zoom in closer to the supermassive black hole: the middle view covers a region about one light year in size and was obtained with the National Radio Astronomy Observatory’s Very Long Baseline Array (VLBA) in the US. The most zoomed-in view was obtained by linking eight telescopes around the world to create a virtual Earth-sized telescope, the Event Horizon Telescope or EHT. This allows astronomers to see very close to the supermassive black hole, into the region where the jets are launched. The lines mark the orientation of polarisation, which is related to the magnetic field in the regions imaged. The ALMA data provides a description of the magnetic field structure along the jet. Therefore the combined information from the EHT and ALMA allows astronomers to investigate the role of magnetic fields from the vicinity of the event horizon (as probed with the EHT on light-day scales) to far beyond the M87 galaxy along its powerful jets (as probed with ALMA on scales of thousand of light-years).

    The values in GHz refer to the frequencies of light at which the different observations were made. The horizontal lines show the scale (in light years) of each of the individual images. Credit: EHT Collaboration; ALMA (ESO/NAOJ/NRAO), Goddi et al.; NASA, ESA and the Hubble Heritage Team (STScI/AURA); VLBA (NRAO), Kravchenko et al.; J. C. Algaba, I. Martí-Vidal.

    4
    This image shows a view of the jet in the Messier 87 galaxy in polarised light. The image was obtained with ALMA and captures the part of the jet, with a size of 6000 light years, closer to the centre of the galaxy. The lines mark the orientation of polarisation, which is related to the magnetic field in the region imaged. This ALMA image therefore indicates what the structure of the magnetic field along the jet looks like.

    Messier 87*, The first image of the event horizon of a black hole. This is the supermassive black hole at the center of the galaxy Messier 87. Image via JPL/ Event Horizon Telescope Collaboration released on 10 April 2019.

    The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. In coordinated press conferences across the globe, EHT researchers revealed that they succeeded, unveiling the first direct visual evidence of the supermassive black hole in the centre of Messier 87 and its shadow. The shadow of a black hole seen here is the closest we can come to an image of the black hole itself, a completely dark object from which light cannot escape. The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across. While this may sound large, this ring is only about 40 microarcseconds across — equivalent to measuring the length of a credit card on the surface of the Moon. Although the telescopes making up the EHT are not physically connected, they are able to synchronize their recorded data with atomic clocks — hydrogen masers — which precisely time their observations. These observations were collected at a wavelength of 1.3 mm during a 2017 global campaign. Each telescope of the EHT produced enormous amounts of data – roughly 350 terabytes per day – which was stored on high-performance helium-filled hard drives.

    Katie Bouman of Harvard Smithsonian Observatory for Astrophysics(US), headed to California Institute of Technology(US), with EHT hard drives from Messier 87.

    These data were flown to highly specialised supercomputers — known as correlators — at the MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) and Massachusettes Institute of Technology(US) Haystack Observatory to be combined. They were then painstakingly converted into an image using novel computational tools developed by the collaboration. Credit: EHT Collaboration.

    5
    Messier 87 Captured by ESO’s Very Large Telescope. Credit: ESO

    European Southern Observatory(EU) , Very Large Telescope at Cerro Paranal in the Atacama Desert •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    6
    This artist’s impression depicts the black hole [Messier 87*] at the heart of the enormous elliptical galaxy Messier 87 . This black hole was chosen as the object of paradigm-shifting observations by the Event Horizon Telescope. The superheated material surrounding the black hole is shown, as is the relativistic jet launched by M87’s black hole. Credit: M. Kornmesser/European Southern Observatory(EU)/

    7
    This image shows the contribution of ALMA and ESO’s Atacama Pathfinder Experiment(CL) to the EHT. The left hand image shows a reconstruction of the black hole image using the full array of the Event Horizon Telescope (including ALMA and APEX); the right-hand image shows what the reconstruction would look like without data from ALMA and APEX. The difference clearly shows the crucial role that ALMA and APEX played in the observations. Credit: EHT Collaboration.

    The Event Horizon Telescope (EHT) collaboration, who produced the first ever image of a black hole, has today revealed a new view of the massive object at the centre of the Messier 87 galaxy: how it looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole. This video summarises the discovery.

    This zoom video starts with a view of ALMA, a telescope in which ESO is a partner and that is part of the Event Horizon Telescope, and zooms-in on the heart of M87, showing successively more detailed observations. At the end of the video, we see the first ever image of a black hole — first released in 2019 — followed by a new image released in 2021: how this supermassive object looks in polarised light. This is the first time astronomers have been able to measure polarisation, a signature of magnetic fields, this close to the edge of a black hole.
    Credit: ESO/L. Calçada, Digitized Sky Survey 2, ESA/Hubble, RadioAstron, De Gasperin et al., Kim et al., EHT Collaboration. Music: Niklas Falcke.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

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

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

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    ALMA-In Search of our Cosmic Origins

     
  • richardmitnick 1:02 pm on March 18, 2021 Permalink | Reply
    Tags: ALMA [The Atacama Large Millimeter/submillimeter Array] (CL), , , , , ,   

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL): “Powerful stratospheric winds measured on Jupiter for the first time” 

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

    From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL)

    Nicolás Lira
    Education and Public Outreach Coordinator
    Joint ALMA Observatory, Santiago – Chile
    Phone: +56 2 2467 6519
    Cell phone: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Masaaki Hiramatsu
    Education and Public Outreach Officer, NAOJ Chile
    Observatory
, Tokyo – Japan
    Phone: +81 422 34 3630
    Email: hiramatsu.masaaki@nao.ac.jp

    Bárbara Ferreira
    ESO Public Information Officer
    Garching bei München, Germany
    Phone: +49 89 3200 6670
    Email: pio@eso.org

    Iris Nijman
    Public Information Officer
    National Radio Astronomy Observatory Charlottesville, Virginia – USA
    Cell phone: +1 (434) 249 3423
    Email: alma-pr@nrao.edu

    Using the Atacama Large Millimeter/submillimeter Array (ALMA)(CL), a team of astronomers have directly measured winds in Jupiter’s middle atmosphere for the first time. By analyzing the aftermath of a comet collision from the 1990s, the researchers have revealed incredibly powerful winds, with speeds of up to 1450 kilometers an hour, near Jupiter’s poles. They could represent what the team has described as a “unique meteorological beast in our Solar System.”

    Jupiter is famous for its distinctive red and white bands: swirling clouds of moving gas that astronomers traditionally use to track winds in Jupiter’s lower atmosphere. Astronomers have also seen, near Jupiter’s poles, the vivid glow known as aurorae, which appear to be associated with strong winds in the planet’s upper atmosphere. But until now, researchers had never been able to directly measure wind patterns between these two atmospheric layers in the stratosphere.

    Measuring wind speeds in Jupiter’s stratosphere using cloud-tracking techniques is impossible because of the absence of clouds in this part of the atmosphere. However, astronomers were provided with an alternative measuring aid in the form of comet Shoemaker-Levy 9, which collided with the gas giant spectacularly in 1994. This impact produced new molecules in Jupiter’s stratosphere, where they have been moving with the winds ever since.

    A team of astronomers, led by Thibault Cavalié of the Laboratoire d’Astrophysique de Bordeaux(FR), have now tracked one of these molecules — hydrogen cyanide — to directly measure stratospheric “jets” on Jupiter. Scientists use the word “jets” to refer to narrow bands of wind in the atmosphere, like Earth’s jet streams.

    “The most spectacular result is the presence of strong jets, with speeds of up to 400 meters per second, which are located under the aurorae near the poles,” says Cavalié. These wind speeds, equivalent to about 1450 kilometers an hour, are more than twice the maximum storm speeds reached in Jupiter’s Great Red Spot and over three times the wind speed measured on Earth’s strongest tornadoes.

    “Our detection indicates that these jets could behave like a giant vortex with a diameter of up to four times that of Earth and some 900 kilometers in height,” explains co-author Bilal Benmahi, also of the Bordeaux Observatory [Laboratory of Astrophysics of Bordeaux](FR). “A vortex of this size would be a unique meteorological beast in our Solar System,” Cavalié adds.

    Astronomers were aware of strong winds near Jupiter’s poles but much higher up in the atmosphere, hundreds of kilometers above the new study’s focus area, which is published today in Astronomy & Astrophysics. Previous studies predicted that these upper-atmosphere winds would decrease in velocity and disappear well before reaching as deep as the stratosphere. “The new ALMA data tell us the contrary,” says Cavalié, adding that finding these strong stratospheric winds near Jupiter’s poles was a “real surprise”.

    The team used 42 of ALMA’s 66 high-precision antennas, located in the Atacama Desert in northern Chile, to analyze the hydrogen cyanide molecules moving around in Jupiter’s stratosphere since the impact of Shoemaker-Levy 9. The ALMA data allowed them to measure the Doppler shift — tiny changes in the frequency of the radiation emitted by the molecules — caused by the winds in this region of the planet. “By measuring this shift, we were able to deduce the speed of the winds much like one could deduce the speed of a passing train by the change in the frequency of the train whistle,” explains study co-author Vincent Hue, a planetary scientist at the Southwest Research Institute(US).

    In addition to the surprising polar winds, the team also used ALMA to confirm the existence of strong stratospheric winds around the planet’s equator by directly measuring their speed, also for the first time. The jets spotted in this part of the planet have average speeds of about 600 kilometers an hour.

    The ALMA observations required to track stratospheric winds in both the poles and equator of Jupiter took less than 30 minutes of telescope time. “The high levels of detail we achieved in this short time really demonstrate the power of the ALMA observations,” says Thomas Greathouse, a scientist at the Southwest Research Institute in the US and co-author of the study. “It is astounding to me to see the first direct measurement of these winds.”

    “These ALMA results open a new window for the study of Jupiter’s auroral regions, which was really unexpected just a few months back,” says Cavalié. “They also set the stage for similar yet more extensive measurements to be made by the JUICE mission and its Submillimetre Wave Instrument,” Greathouse adds, referring to the European Space Agency’s JUpiter ICy moons Explorer, which is expected to launch into space next year.

    European Southern Observatory(EU) ELT 39 meter telescope to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    The telescope will be capable of making highly detailed observations of the planet’s aurorae, giving us further insight into Jupiter’s atmosphere.

    Additional Information

    This research is presented in the paper “First direct measurement of auroral and equatorial jets in the stratosphere of Jupiter” published today in Astronomy & Astrophysics.

    The team is composed of T. Cavalié (Laboratoire d’Astrophysique de Bordeaux(FR); Observatoire de Paris(FR), Paris Sciences et Lettres University(FR)), B. Benmahi (LAB), V. Hue (Southwest Research Institute [SwRI](US), R. Moreno, E. Lellouch (LESIA), T. Fouchet (LESIA), P. Hartogh (MPG institute for solar system research[Institut für Sonnensystemforschung][MPS](DE), L. Rezac (MPS), T. K. Greathouse (SwRI), G. R. Gladstone (SwRI), J. A. Sinclair (NASA JPL-Caltech(US)), M. Dobrijevic (LAB), F. Billebaud (LAB) and C. Jarchow (MPS).

    1
    This image shows an artist’s impression of winds in Jupiter’s stratosphere near the planet’s south pole, with the blue lines representing wind speeds. These lines are superimposed on a real image of Jupiter, taken by the JunoCam imager aboard NASA’s Juno spacecraft. Jupiter’s famous bands of clouds are located in the lower atmosphere, where winds have previously been measured. But tracking winds right above this atmospheric layer, in the stratosphere, is much harder since no clouds exist there. By analyzing the aftermath of a comet collision from the 1990s and using the ALMA telescope, researchers have been able to reveal incredibly powerful stratospheric winds, with speeds of up to 1450 kilometres an hour, near Jupiter’s poles. Credit: European Southern Observatory(EU)/L. Calçada & NASA JPL-Caltech(US)/Southwest Research Institute(US)/Malin Space Science Systems(US).

    2
    This image, taken with the MPG/ESO 2.2-metre telescope and the IRAC instrument, shows comet Shoemaker–Levy 9 impacting Jupiter in July 1994. Credit: European Southern Observatory(EU).

    3
    Amazing image of Jupiter taken in infrared light on the night of 17 August 2008 with the Multi-Conjugate Adaptive Optics Demonstrator (MAD) prototype instrument mounted on European Southern Observatory(EU) VLT at Cerro Paranal in the Atacama Desert.

    European Southern Observatory(EU) VLT at Cerro Paranal in the Atacama Desert , •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo.

    This false colour photo is the combination of a series of images taken over a time span of about 20 minutes, through three different filters (2, 2.14, and 2.16 microns). The image sharpening obtained is about 90 milli-arcseconds across the whole planetary disc, a real record on similar images taken from the ground. This corresponds to seeing details about 300 km wide on the surface of the giant planet. The great red spot is not visible in this image as it was on the other side of the planet during the observations. The observations were done at infrared wavelengths where absorption due to hydrogen and methane is strong. This explains why the colours are different from how we usually see Jupiter in visible-light. This absorption means that light can be reflected back only from high-altitude hazes, and not from deeper clouds. These hazes lie in the very stable upper part of Jupiter’s troposphere, where pressures are between 0.15 and 0.3 bar. Mixing is weak within this stable region, so tiny haze particles can survive for days to years, depending on their size and fall speed. Additionally, near the planet’s poles, a higher stratospheric haze (light blue regions) is generated by interactions with particles trapped in Jupiter’s intense magnetic field. Credit: European Southern Observatory(EU)/F. Marchis, M. Wong, E. Marchetti, P. Amico, S. Tordo.

    This animation of Jupiter was created from real images taken with the NASA/ESA Hubble Space Telescope(US). The impact sites of the fragments of comet Shoemaker–Levy 9, which hit Jupiter in 1994, are visible in dark brown in the planet’s southern hemisphere. Credit: European Southern Observatory(EU)/M. Kornmesser, NASA/ESA.

    This video shows an artist’s animation of winds in Jupiter’s stratosphere near the planet’s south pole, with the blue lines representing wind speeds. These lines are superimposed on a real image of Jupiter, taken by the JunoCam imager aboard NASA’s Juno spacecraft. Jupiter’s famous bands of clouds are located in the lower atmosphere, where winds have previously been measured. But tracking winds right above this atmospheric layer, in the stratosphere, is much harder since no clouds exist there. By analyzing the aftermath of a comet collision from the 1990s and using the ALMA telescope, researchers have been able to reveal incredibly powerful stratospheric winds, with speeds of up to 1450 kilometres an hour, near Jupiter’s poles. Credit:European Southern Observatory(EU)/L. Calçada & NASA JPL-Caltech(US)/Southwest Research Institute(US)/Malin Space Science Systems(US)

    See the full article here.

    See also the European Southern Observatory(EU) article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Atacama Large Millimeter/submillimeter Array (ALMA) (CL) , 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 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

     
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