From ALMA (CL): “Astronomers make first clear detection of a moon-forming disc around an exoplanet”

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

From ALMA (CL)

22 July, 2021

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

All general references:
ALMA Observatory (CL)
European Southern Observatory(EU)
National Astronomical Observatory of Japan(JP)
National Radio Astronomy Observatory(US)

This image, taken with the Atacama Large Millimeter/submillimeter Array (ALMA) shows wide (left) and close-up (right) views of the moon-forming disc surrounding PDS 70c, a young Jupiter-like planet nearly 400 light-years away. The close-up view shows PDS 70c and its circumplanetary disc centre-front, with the larger circumstellar ring-like disc taking up most of the right-hand side of the image. The star PDS 70 is at the centre of the wide-view image on the left. Two planets have been found in the system-PDS 70c and PDS 70b, the latter not being visible in this image. They have carved a cavity in the circumstellar disc as they gobbled up material from the disc itself, growing in size. In this process, PDS 70c acquired its own circumplanetary disc, which contributes to the growth of the planet and where moons can form. This circumplanetary disc is as large as the Sun-Earth distance and has enough mass to form up to three satellites the size of the Moon. Credit: Benisty et al. /ALMA (ESO/NAOJ/NRAO).

Using the Atacama Large Millimeter /submillimeter Array (ALMA), in which the European Southern Observatory (ESO) is a partner, astronomers have unambiguously detected the presence of a disc around a planet outside our Solar System for the first time. The observations will shed new light on how moons and planets form in young stellar systems.

“Our work presents a clear detection of a disc in which satellites could be forming,” says Myriam Benisty, a researcher at the University of Grenoble Alpes [Université Grenoble Alpes] (FR), and at the University of Chile [Universidad de Chile] (CL), who led the new research published today in The Astrophysical Journal Letters. “Our ALMA observations were obtained at such exquisite resolution that we could clearly identify that the disc is associated with the planet and we are able to constrain its size for the first time,” she adds.

The disc in question, called a circumplanetary disc, surrounds the exoplanet PDS 70c, one of two giant, Jupiter-like planets orbiting a star nearly 400 light-years away. Astronomers had found hints of a “moon-forming” disc around this exoplanet before but, since they could not clearly tell the disc apart from its surrounding environment, they could not confirm its detection — until now.

In addition, with the help of ALMA, Benisty and her team found that the disc has about the same diameter as the distance from our Sun to the Earth and enough mass to form up to three satellites the size of the Moon.

But the results are not only key to finding out how moons arise. “These new observations are also extremely important to prove theories of planet formation that could not be tested until now,” says Jaehan Bae, a researcher from the Earth and Planets Laboratory of the Carnegie Institution for Science (US), and author on the study.

Planets form in dusty discs around young stars, carving out cavities as they gobble up material from this circumstellar disc to grow. In this process, a planet can acquire its own circumplanetary disc, which contributes to the growth of the planet by regulating the amount of material falling onto it. At the same time, the gas and dust in the circumplanetary disc can come together into progressively larger bodies through multiple collisions, ultimately leading to the birth of moons.

But astronomers do not yet fully understand the details of these processes. “In short, it is still unclear when, where, and how planets and moons form,” explains ESO Research Fellow Stefano Facchini, also involved in the research.

“More than 4000 exoplanets have been found until now, but all of them were detected in mature systems. PDS 70b and PDS 70c, which form a system reminiscent of the Jupiter-Saturn pair, are the only two exoplanets detected so far that are still in the process of being formed,” explains Miriam Keppler, researcher at the MPG Institute for Astronomy [MPG Institut für Astronomie](DE) and one of the co-authors of the study [1].

“This system therefore offers us a unique opportunity to observe and study the processes of planet and satellite formation,” Facchini adds.

PDS 70b and PDS 70c, the two planets making up the system, were first discovered using ESO’s Very Large Telescope (VLT) in 2018 and 2019 respectively, and their unique nature means they have been observed with other telescopes and instruments many times since [2].

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.

The latest high resolution ALMA observations have now allowed astronomers to gain further insights into the system. In addition to confirming the detection of the circumplanetary disc around PDS 70c and studying its size and mass, they found that PDS 70b does not show clear evidence of such a disc, indicating that it was starved of dust material from its birth environment by PDS 70c.

An even deeper understanding of the planetary system will be achieved with ESO’s Extremely Large Telescope (ELT), currently under construction on Cerro Armazones in the Chilean Atacama desert.

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 ELT will be key for this research since, with its much higher resolution, we will be able to map the system in great detail,” says co-author Richard Teague, a researcher at the Center for Astrophysics | Harvard & Smithsonian, USA. In particular, by using the ELT’s Mid-infrared ELT Imager and Spectrograph (METIS), the team will be able to look at the gas motions surrounding PDS 70c to get a full 3D picture of the system.

Notes

[1] Despite the similarity with the Jupiter-Saturn pair, note that the disc around PDS 70c is about 500 times larger than Saturn’s rings.

[2] PDS 70b was discovered using the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument, while PDS 70c was found using the VLT’s Multi Unit Spectroscopic Explorer (MUSE). The two-planet system has been investigated using the X-shooter instrument too, also installed on ESO’s VLT.

European Southern Observatory(EU) SPHERE extreme adaptive optics system and coronagraphic facility on the VLT UT3, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level.

European Southern Observatory(EU) MUSE on Yepun (UT4) on the Very Large Telescope, Cerro Paranal (CL)

ESO X-shooter on VLT on UT2 at Cerro Paranal, Chile.

The team is composed of Myriam Benisty (Joint Franco-Chilean International Astronomy Unit [Unidad Mixta franco chilena de astronomía], National Centre for Scientific Research [Centre national de la recherche scientifique, [CNRS] (FR), Departamento de Astronomía, University of Chile [Universidad de Chile] (CL), Santiago de Chile, Chile and University of Grenoble Alpes [Université Grenoble Alpes] (FR), CNRS, Grenoble, France [UGA]), Jaehan Bae (Earth and Planets Laboratory, Carnegie Institution for Science (US), Washington DC, USA), Stefano Facchini (European Southern Observatory, Garching bei München, Germany), Miriam Keppler (MPG Institute for Astronomy [MPG Institut für Astronomie](DE), Heidelberg, Germany [MPIA]), Richard Teague (Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA, USA [CfA]), Andrea Isella (Department of Physics and Astronomy, Rice University (US), Houston, TX, USA), Nicolas T. Kurtovic (MPIA), Laura M. Perez (Departamento de Astronomía, Universidad de Chile, Santiago de Chile, Chile [UCHILE]), Anibal Sierra (UCHILE), Sean M. Andrews (CfA), John Carpenter (Joint ALMA Observatory, Santiago de Chile, Chile), Ian Czekala (Department of Astronomy and Astrophysics, Pennsylvania State University (US), PA, USA, Center for Exoplanets and Habitable Worlds, Davey Laboratory, Pennsylvania State University, PA, USA, Center for Astrostatistics, Davey Laboratory, Pennsylvania State University, PA, USA and Institute for Computational & Data Sciences, Pennsylvania State University, PA, USA), Carsten Dominik (Anton Pannekoek Institute for Astronomy, University of Amsterdam [Universiteit van Amsterdam] (NL), The Netherlands), Thomas Henning (MPIA), Francois Menard (UGA), Paola Pinilla (MPIA and Mullard Space Science Laboratory, University College London (UK), Holmbury St Mary, Dorking, UK) and Alice Zurlo (Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Diego Portales University [Universidad Diego Portales] (CL), Santiago de Chile, Chile and Escuela de Ingeniería Industrial, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Santiago de Chile, Chile).

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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) (EU), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) (CA) 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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

From European Southern Observatory (EU) (CL) : “Astronomers make first clear detection of a moon-forming disc around an exoplanet”

From European Southern Observatory (EU) (CL)

22 July 2021

Myriam Benisty
University of Chile [Universidad de Chile] (CL) and University of Grenoble Alpes [Université Grenoble Alpes] (FR)
Santiago de Chile, Chile
myriam.benisty@univ-grenoble-alpes.fr

Jaehan Bae
Earth and Planets Laboratory, Carnegie Institution for Science (US)
Washington DC, USA
Email: jbae@carnegiescience.edu

Stefano Facchini
European Southern Observatory
Garching bei München, Germany
Email: stefano.facchini@eso.org

Miriam Keppler
MPG Institute for Astronomy [MPG Institut für Astronomie](DE)
Heidelberg, Germany
Email: keppler@mpia.de

Richard Teague
Harvard Smithsonian Center for Astrophysics (US)
Cambridge, MA, USA
Email: richard.d.teague@cfa.harvard.edu

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Cell: +49 151 241 664 00
Email: press@eso.org

Wide and close-up views of a moon-forming disc as seen with ALMA.
Using the Atacama Large Millimetre/submillimeter Array (ALMA) [below], in which the European Southern Observatory (ESO) is a partner, astronomers have unambiguously detected the presence of a disc around a planet outside our Solar System for the first time. The observations will shed new light on how moons and planets form in young stellar systems.

“Our work presents a clear detection of a disc in which satellites could be forming,” says Myriam Benisty, a researcher at the University of Grenoble Alpes [Université Grenoble Alpes] (FR), and at the University of Chile [Universidad de Chile] (CL), who led the new research published today in The Astrophysical Journal Letters. “Our ALMA observations were obtained at such exquisite resolution that we could clearly identify that the disc is associated with the planet and we are able to constrain its size for the first time,” she adds.

The disc in question, called a circumplanetary disc, surrounds the exoplanet PDS 70c, one of two giant, Jupiter-like planets orbiting a star nearly 400 light-years away. Astronomers had found hints of a “moon-forming” disc around this exoplanet before but, since they could not clearly tell the disc apart from its surrounding environment, they could not confirm its detection — until now.

In addition, with the help of ALMA, Benisty and her team found that the disc has about the same diameter as the distance from our Sun to the Earth and enough mass to form up to three satellites the size of the Moon.

But the results are not only key to finding out how moons arise. “These new observations are also extremely important to prove theories of planet formation that could not be tested until now,” says Jaehan Bae, a researcher from the Earth and Planets Laboratory of the Carnegie Institution for Science (US), and author on the study.

Planets form in dusty discs around young stars, carving out cavities as they gobble up material from this circumstellar disc to grow. In this process, a planet can acquire its own circumplanetary disc, which contributes to the growth of the planet by regulating the amount of material falling onto it. At the same time, the gas and dust in the circumplanetary disc can come together into progressively larger bodies through multiple collisions, ultimately leading to the birth of moons.

But astronomers do not yet fully understand the details of these processes. “In short, it is still unclear when, where, and how planets and moons form,” explains ESO Research Fellow Stefano Facchini, also involved in the research.

“More than 4000 exoplanets have been found until now, but all of them were detected in mature systems. PDS 70b and PDS 70c, which form a system reminiscent of the Jupiter-Saturn pair, are the only two exoplanets detected so far that are still in the process of being formed,” explains Miriam Keppler, researcher at the MPG Institute for Astronomy [MPG Institut für Astronomie](DE) and one of the co-authors of the study [1].

“This system therefore offers us a unique opportunity to observe and study the processes of planet and satellite formation,” Facchini adds.

PDS 70b and PDS 70c, the two planets making up the system, were first discovered using ESO’s Very Large Telescope (VLT) [below] in 2018 and 2019 respectively, and their unique nature means they have been observed with other telescopes and instruments many times since [2].

The latest high resolution ALMA observations have now allowed astronomers to gain further insights into the system. In addition to confirming the detection of the circumplanetary disc around PDS 70c and studying its size and mass, they found that PDS 70b does not show clear evidence of such a disc, indicating that it was starved of dust material from its birth environment by PDS 70c.

An even deeper understanding of the planetary system will be achieved with ESO’s Extremely Large Telescope (ELT) [below], currently under construction on Cerro Armazones in the Chilean Atacama desert. “The ELT will be key for this research since, with its much higher resolution, we will be able to map the system in great detail,” says co-author Richard Teague, a researcher at the Harvard Smithsonian Center for Astrophysics (US). In particular, by using the ELT’s Mid-infrared ELT Imager and Spectrograph (METIS), the team will be able to look at the gas motions surrounding PDS 70c to get a full 3D picture of the system.

Notes

[1] Despite the similarity with the Jupiter-Saturn pair, note that the disc around PDS 70c is about 500 times larger than Saturn’s rings.

[2] PDS 70b was discovered using the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument, while PDS 70c was found using the VLT’s Multi Unit Spectroscopic Explorer (MUSE). The two-planet system has been investigated using the X-shooter instrument too, also installed on ESO’s VLT.

European Southern Observatory(EU) SPHERE extreme adaptive optics system and coronagraphic facility on the VLT UT3, Cerro Paranal, Chile, with an elevation of 2,635 metres (8,645 ft) above sea level.

European Southern Observatory(EU) MUSE on Yepun (UT4) on the Very Large Telescope, Cerro Paranal (CL)

ESO X-shooter on VLT on UT2 at Cerro Paranal, Chile.

More information

This research was presented in a paper in The Astrophysical Journal Letters.

The team is composed of Myriam Benisty (Joint Franco-Chilean International Astronomy Unit [Unidad Mixta franco chilena de astronomía], National Centre for Scientific Research [Centre national de la recherche scientifique, [CNRS] (FR), Departamento de Astronomía, University of Chile [Universidad de Chile] (CL), Santiago de Chile, Chile and University of Grenoble Alpes [Université Grenoble Alpes] (FR), CNRS, Grenoble, France [UGA]), Jaehan Bae (Earth and Planets Laboratory, Carnegie Institution for Science (US), Washington DC, USA), Stefano Facchini (European Southern Observatory, Garching bei München, Germany), Miriam Keppler (MPG Institute for Astronomy [MPG Institut für Astronomie](DE), Heidelberg, Germany [MPIA]), Richard Teague (Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA, USA [CfA]), Andrea Isella (Department of Physics and Astronomy, Rice University (US), Houston, TX, USA), Nicolas T. Kurtovic (MPIA), Laura M. Perez (Departamento de Astronomía, Universidad de Chile, Santiago de Chile, Chile [UCHILE]), Anibal Sierra (UCHILE), Sean M. Andrews (CfA), John Carpenter (Joint ALMA Observatory, Santiago de Chile, Chile), Ian Czekala (Department of Astronomy and Astrophysics, Pennsylvania State University (US), PA, USA, Center for Exoplanets and Habitable Worlds, Davey Laboratory, Pennsylvania State University, PA, USA, Center for Astrostatistics, Davey Laboratory, Pennsylvania State University, PA, USA and Institute for Computational & Data Sciences, Pennsylvania State University, PA, USA), Carsten Dominik (Anton Pannekoek Institute for Astronomy, University of Amsterdam [Universiteit van Amsterdam] (NL), The Netherlands), Thomas Henning (MPIA), Francois Menard (UGA), Paola Pinilla (MPIA and Mullard Space Science Laboratory, University College London (UK), Holmbury St Mary, Dorking, UK) and Alice Zurlo (Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Diego Portales University [Universidad Diego Portales] (CL), Santiago de Chile, Chile and Escuela de Ingeniería Industrial, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Santiago de Chile, Chile).

See the full article here .
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European Southern Observatory (EU)(CL) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

European Southern Observatory(EU)La Silla Observatory 600 km north of Santiago de Chile at an altitude of 2400 metres.

ESO New Technology Telescope at Cerro La Silla , Chile, at an altitude of 2400 metres.

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.

Glistening against the awesome backdrop of the night sky aboveESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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).

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).

A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at ESO Cerro Paranal site. The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the University of Wisconsin–Madison and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

From ALMA(CL): “EHT pinpoints dark heart of the nearest radio galaxy”

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

From 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

All general references:
ALMA Observatory (CL)
European Southern Observatory(EU)
National Astronomical Observatory of Japan(JP)
National Radio Astronomy Observatory(US)

An international team anchored by the Event Horizon Telescope (EHT) Collaboration, which is known for capturing the first image of a black hole in the galaxy Messier 87, has now imaged the heart of the nearby radio galaxy Centaurus A in unprecedented detail. The astronomers pinpoint the location of the central supermassive black hole and reveal how a gigantic jet is being born. Most remarkably, only the outer edges of the jet seem to emit radiation, which challenges our theoretical models of jets. This work, led by Michael Janssen from the MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) in Bonn and Radboud University Nijmegen [Radboud Universiteit](NL) is published in Nature Astronomy on July 19th.

At radio wavelengths Centaurus A emerges as one of the largest and brightest objects in the night sky. After it was identified as one of the first known extragalactic radio sources in 1949, Centaurus A has been studied extensively across the entire electromagnetic spectrum by a variety of radio, infrared, optical, X-ray, and gamma-ray observatories. At the center of Centaurus A lies a black hole with the mass of 55 million suns, which is right between the mass scales of the Messier 87 black hole (six and a half billion suns) and the one in the center of our own galaxy (about four million suns).

In a new paper in Nature Astronomy, data from the 2017 EHT observations have been analyzed to image Centaurus A in unprecedented detail. “This allows us for the first time to see and study an extragalactic radio jet on scales smaller than the distance light travels in one day. We see up close and personally how a monstrously gigantic jet launched by a supermassive black hole is being born”, says astronomer Michael Janssen.

Highest resolution image of Centaurus A obtained with the Event Horizon Telescope on top of a color composite image of the entire galaxy. Credit: Radboud University; European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL)/WFI; MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) A. Weiss et al./ESO/APEX/; National Aeronautics Space Agency (US)/Chandra X-ray Center (US)/ R. Kraft et al.Harvard Smithsonian Center for Astrophysics (US)/; M. Janssen et al. EHT.

National Aeronautics and Space Administration Chandra X-ray telescope(US)

Wide Field Imager on the 2.2 meter MPG/ESO telescope at Cerro LaSilla (CL)

MPG Institute for Astronomy [Max-Planck-Institut für Astronomie](DE)European Southern Observatory(EU)2.2 meter telescope at Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

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).

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Event Horizon Telescope Array

Arizona Radio Observatory

University of Arizona Radio Observatory(US) at NOAO Kitt Peak National Observatory(US), AZ USA, U Arizona Department of Astronomy and Steward Observatory(US) at altitude 2,096 m (6,877 ft).

ESO APEX
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).

CARMA
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).

NAOJ Atacama Submillimeter Telescope Experiment (ASTE)

NAOJ 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).

CfA Submillimeter Observatory

CFA Harvard Smithsonian Submillimeter Array on MaunaKea, Hawaii, USA, Altitude 4,205 m (13,796 ft).

Greenland Telescope

The Greenland Telescope is an international collaboration between: The Academia Sinica Institute of Astronomy and Astrophysics(project leaders); The Smithsonian Astrophysical Observatory of the Harvard–Smithsonian Center for Astrophysics (US) The The National Radio Astronomy Observatory(US); and The Haystack Observatory of the Massachusetts Institute of Technology(US) at an altitude of 3,210 meters (10,530 feet).

(IRAM) 30m
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 NOEMA, France

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.

James Clerk Maxwell Telescope

East Asian Observatory James Clerk Maxwell Telescope MaunaKea Hawai’i(US)altitude 4207 m (13802 ft) above sea level.

Large Millimeter Telescope Alfonso Serrano

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

ESO/NRAO/NAOJ ALMA Array.
European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.[/caption]

South Pole Telescope

South Pole Telescope SPTPOL. The SPT collaboration is made up of over a dozen (mostly North American) institutions, including The University of Chicago (US); The University of California Berkeley (US); Case Western Reserve University (US); Harvard/Smithsonian Astrophysical Observatory (US); The University of Colorado-Boulder (US); McGill University(CA); The University of Illinois, Urbana-Champaign (US); The University of California-Davis (US); Ludwig Maximilians Universität München(DE); DOE’s Argonne National Laboratory (US); and The National Institute for Standards and Technology (US). 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.
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Compared to all previous high-resolution observations, the jet launched in Centaurus A is imaged at a tenfold higher frequency and sixteen times sharper resolution. With the resolving power of the EHT, we can now link the vast scales of the source, which are as big as 16 times the angular diameter of the Moon on the sky, to their origin near the black hole in a region of merely the width of an apple on the Moon when projected on the sky. That is a magnification factor of one billion.

Understanding jets

Supermassive black holes residing in the center of galaxies like Centaurus A are feeding off gas and dust that is attracted by their enormous gravitational pull. This process releases massive amounts of energy and the galaxy is said to become ‘active’. Most matter lying close to the edge of the black hole falls in. However, some of the surrounding particles escape moments before capture and are blown far out into space: Jets – one of the most mysterious and energetic features of galaxies – are born.

Astronomers have relied on different models of how matter behaves near the black hole to better understand this process. But they still do not know exactly how jets are launched from its central region and how they can extend over scales that are larger than their host galaxies without dispersing out. The EHT aims to resolve this mystery.

The new image shows that the jet launched by Centaurus A is brighter at the edges compared to the center. This phenomenon is known from other jets, but has never been seen so pronouncedly before. “Now we are able to rule out theoretical jet models that are unable to reproduce this edge-brightening. It’s a striking feature that will help us better understand jets produced by black holes”, says Matthias Kadler, TANAMI leader and professor for astrophysics at the Julius Maximilian University of Würzburg [Julius-Maximilians-Universität Würzburg] (DE) in Germany.

Future observations

With the new EHT observations of the Centaurus A jet, the likely location of the black hole has been identified at the launching point of the jet. Based on this location, the researchers predict that future observations at an even shorter wavelength and higher resolution would be able to photograph the central black hole of Centaurus A. This will require the use of space-based satellite observatories.

“These data are from the same observing campaign that delivered the famous image of the black hole in M87. The new results show that the EHT provides a treasure trove of data on the rich variety of black holes and there is still more to come”, says Heino Falcke, EHT board member and professor for Astrophysics at Radboud University.

Additional Information

To observe the Centaurus A galaxy with this unprecedentedly sharp resolution at a wavelength of 1.3 mm, the EHT collaboration used Very Long Baseline Interferometry (VLBI), the same technique with which the famous image of the black hole in M87 was made.

European Very Long Baseline Interferometry Network

An alliance of eight telescopes around the world, of which ALMA is the most sensitive element, joined together to create the virtual Earth-sized Event Horizon Telescope. The EHT collaboration involves more than 300 researchers from Africa, Asia, Europe, North and South America.

The EHT consortium consists of 13 stakeholder institutes: the Academia Sinica Institute of Astronomy and Astrophysics, the University of Arizona (US), the University of Chicago (US), the East Asian Observatory, Goethe University [Goethe-Universität] Frankfurt(DE), Institut de Radioastronomie Millimétrique (MPG/CNRS/IGN), Large Millimeter Telescope, MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE), MIT Haystack Observatory (US), National Astronomical Observatory of Japan [国立天文台](JP), Perimeter Institute for Theoretical Physics (CA), Radboud University Nijmegen [Radboud Universiteit](NL) and the Center for Astrophysics | Harvard Smithsonian Center for Astrophysics (US).

See the full article here .

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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) (EU), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) (CA) 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. (US) (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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

From Sky & Telescope : “Gravitationally Unstable Disk May Collapse to Form Planets”

From Sky & Telescope

July 16, 2021
Lauren Sgro

Astronomers investigate the spiral arms of a young star’s disk and find evidence of a disk so massive that it could collapse to form planets.

The protoplanetary disk of Elias 2-27, shown with the dust continuum data in blue, along with different forms of carbon monoxide shown in yellow and red. The top panel shows the dust in blue along with gas probed at different velocities. Each image shows all the gas that travels at the specific velocity measured. The bottom panel is a composite of all dust and gas observed. Credit: ALMA (European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL)/National Astronomy Observatory of Japan (JP)/B. Saxton National Radio Astronomy Observatory (US))/T. Paneque-Carreño (University of Chile [Universidad de Chile] (CL)).

Astronomers have found the first signposts of a gravitationally unstable disk around the young star Elias 2-27 — the first evidence to support this method of giant planet formation.

Protoplanetary disks of gas and dust leftover from stellar formation are known as the birthplace of planets. Astronomers understand that these disks give way to planets, but they’re still working to determine the exact evolution from dust to new worlds.

There’s more than one way to form a planet, and one path might be gravitational instability – when disks become so massive that they begin to fragment and cave in on themselves, directly collapsing into planets or forming spiral arms that trap material for future planet formation. An already-formed giant planet or interactions with a nearby star can also create spirals, but spiral structure born out of gravitational instability carries special characteristics.

A team led by Cassandra Hall (University of Georgia (US)) was the first to predict what the markers of gravitational instability might look like. Hall and collaborators used simulations to determine the telltale sign of gravitational instability in a disk, affectionately dubbed the “wiggle.” This wiggle disturbs the disk’s rotation on scales coinciding with the spirals, instead of in one specific location like the swirling kinks caused by planets.

In 2016, scientists at the Atacama Large Millimeter/submillimeter Array (ALMA) first saw spiral arms in the disk of Elias 2-27.

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

Now, research led by Teresa Paneque-Carreño (now at Leiden University [Universiteit Leiden] (NL)), has spotted the hallmark wiggle. The finding makes these spiral arms the first convincing evidence for a gravitationally unstable disk. This study will appear in The Astrophysical Journal.

Evidence for Instability

With Hall’s predictions in mind, Paneque-Carreño’s collaboration used ALMA to observe the dust and gas in Elias 2-27’s disk. The results show that the expansive spiral arms are symmetric, with similar shapes and sizes, as predicted if gravitational instability were at work.

The key piece of evidence for instability, however, is the wiggle. The team used ALMA to observe the motions of carbon monoxide – which traces the harder-to-observe, but more abundant, hydrogen gas – and discovered the sought-after signature. As predicted, this disturbance coincides with the spiral arms in most observations. “It is really amazing to see this confirmation of velocity perturbations that so closely resembles what was predicted,” Hall says, who also worked on the Elias 2-27 studies.

Components of Elias 2-27’s disk, with images of the dust (blue) and carbon monoxide gas (C18O in yellow, 13CO in red) cycled through.
ALMA (ESO/NAOJ/NRAO)/T. Paneque-Carreño (Universidad de Chile), B. Saxton (NRAO).

These signals of gravitational instability also led to the first direct measurement of the mass in a planet-forming disk. Using the ALMA data, collaborator Benedetta Veronesi (University of Milan [Università degli Studi di Milano Statale] (IT)) reported the mass in a companion study that will appear in Astrophysical Journal Letters. Veronesi’s team concluded that Elias 2-27’s disk has 17% the mass of its star, creating conditions ripe for gravitational instabilities. In thinner disks, the star calls the shots with its powerful gravity governing the motions of the disk. But for a massive disk like the one around Elias 2-27, the disk’s own gravity starts to influence its dynamics, which enabled Veronesi’s team to determine its mass budget for future planet formation.

Oddities of Elias 2-27

While the spiral, wiggle, and mass all indicate the disk is experiencing gravitational instability, gaps in that same disk are throwing astronomers for a loop. For instance, there is a gap in the middle of the disk that is devoid of dust – a trait typically attributed to the commotion of a forming planet. However, a planet forming a gap of this size wouldn’t be large enough to form the spiral structure. Even if there were a planet at this location, it would get sucked into the star. On the other hand, gravitational instability cannot explain the gap, even though it explains the spirals.

While neither phenomenon can explain both features, the evidence for gravitational instability is still valid, says Ken Rice (University of Edinburgh (SCT)), who was not involved in the study. “I don’t think the presence of a gap necessarily suggests that spirals aren’t being driven by the gravitational instability.”

This illustration shows how the spiral arms caused by gravitational instability can help dust grains accumulate, which may move on to form planetary systems.
ALMA (ESO/NAOJ/NRAO)/T. Paneque-Carreño (Universidad de Chile), B. Saxton (NRAO).

Paneque-Carreño’s team also finds that the gas in Elias 2-27’s disk is unexpectedly asymmetric, such that the gas is thicker on one side of the disk than the other. The varying layers of gas indicate that material could still be falling onto the disk from the cloud that formed the Elias 2-27 system. This inbound gas might have ignited the gravitational instability and even caused a disk warp that morphed into the currently observed dust gap.

Although more observations are needed to solve the conundrums of Elias 2-27’s disk, the evidence for a massive, gravitationally unstable disk is quite compelling, says Rice.

Astronomers still need to work out how gravitational instability leads to planets — via direct collapse or indirectly, inciting spiral structures that help funnel material. Elias 2-27 and others like it will help astronomers piece together the planet formation puzzle.

See the full article here .

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Sky & Telescope, founded in 1941 by Charles A. Federer Jr. and Helen Spence Federer, has the largest, most experienced staff of any astronomy magazine in the world. Its editors are virtually all amateur or professional astronomers, and every one has built a telescope, written a book, done original research, developed a new product, or otherwise distinguished him or herself.

Sky & Telescope magazine, now in its eighth decade, came about because of some happy accidents. Its earliest known ancestor was a four-page bulletin called The Amateur Astronomer, which was begun in 1929 by the Amateur Astronomers Association in New York City. Then, in 1935, the American Museum of Natural History opened its Hayden Planetarium and began to issue a monthly bulletin that became a full-size magazine called The Sky within a year. Under the editorship of Hans Christian Adamson, The Sky featured large illustrations and articles from astronomers all over the globe. It immediately absorbed The Amateur Astronomer.

Despite initial success, by 1939 the planetarium found itself unable to continue financial support of The Sky. Charles A. Federer, who would become the dominant force behind Sky & Telescope, was then working as a lecturer at the planetarium. He was asked to take over publishing The Sky. Federer agreed and started an independent publishing corporation in New York.

“Our first issue came out in January 1940,” he noted. “We dropped from 32 to 24 pages, used cheaper quality paper…but editorially we further defined the departments and tried to squeeze as much information as possible between the covers.” Federer was The Sky’s editor, and his wife, Helen, served as managing editor. In that January 1940 issue, they stated their goal: “We shall try to make the magazine meet the needs of amateur astronomy, so that amateur astronomers will come to regard it as essential to their pursuit, and professionals to consider it a worthwhile medium in which to bring their work before the public.”

From European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) and From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : “Galactic fireworks- new ESO images reveal stunning features of nearby galaxies”

From European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)

and

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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

16 July 2021

Eric Emsellem
European Southern Observatory
Garching bei München, Germany
Tel: +49 89 3200 6914
Email: eric.emsellem@eso.org

Eva Schinnerer
MPG Institute for Astronomy [MPG Institut für Astronomie](DE)
Heidelberg, Germany
Tel: +49 6221 528 294
Email: schinner@mpia.de

Kathryn Kreckel
Centre for Astronomy of Heidelberg University [Astronomisches Rechen-Institut: Zentrum für Astronomie] (DE)
Heidelberg, Germany
Email: kathryn.kreckel@uni-heidelberg.de

Francesco Belfiore
INAF – Arcetri Observatory [Arcetri Astrophysical Observatory Florence] (IT), Italy
Email: francesco.belfiore@inaf.it

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Tel: +49 89 3200 6670
Cell: +49 151 241 664 00
Email: press@eso.org

A team of astronomers has released new observations of nearby galaxies that resemble colourful cosmic fireworks. The images, obtained with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) [below], show different components of the galaxies in distinct colours, allowing astronomers to pinpoint the locations of young stars and the gas they warm up around them. By combining these new observations with data from the Atacama Large Millimeter/submillimeter Array (ALMA) [below], in which ESO is a partner, the team is helping shed new light on what triggers gas to form stars.

NGC 4303 as seen with MUSE on ESO’s VLT at several wavelengths of light.
This image, taken by the Multi-Unit Spectroscopic Explorer (MUSE) on ESO’s Very Large Telescope (VLT), shows the nearby galaxy NGC 4303. NGC 4303 is a spiral galaxy, with a bar of stars and gas at its centre, located approximately 55 million light-years from Earth in the constellation Virgo. The image is an overlay of observations conducted at different wavelengths of light to map stellar populations and warm gas. The golden glows mainly correspond to clouds of ionised hydrogen, oxygen and sulphur gas, marking the presence of newly born stars, while the bluish regions in the background reveal the distribution of slightly older stars.

The image was taken as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) project, which is making high-resolution observations of nearby galaxies with telescopes operating across the electromagnetic spectrum. Credit: ESO/PHANGS.

European Southern Observatory(EU) MUSE on Yepun (UT4) on the Very Large Telescope, Cerro Paranal (CL)

NGC 4254 as seen with MUSE on ESO’s VLT at several wavelengths of light.
This image, taken with the Multi-Unit Spectroscopic Explorer (MUSE) on ESO’s Very Large Telescope (VLT), shows the nearby galaxy NGC 4254. NGC 4254 is a grand-design spiral galaxy located approximately 45 million light-years from Earth in the constellation Coma Berenices. The image is a combination of observations conducted at different wavelengths of light to map stellar populations and warm gas. The golden glows mainly correspond to clouds of ionised hydrogen, oxygen and sulphur gas, marking the presence of newly born stars, while the bluish regions in the background reveal the distribution of slightly older stars.

The image was taken as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) project, which is making high-resolution observations of nearby galaxies with telescopes operating across the electromagnetic spectrum. Credit: ESO/PHANGS.

See the full article for more individual images.

Astronomers know that stars are born in clouds of gas, but what sets off star formation, and how galaxies as a whole play into it, remains a mystery. To understand this process, a team of researchers has observed various nearby galaxies with powerful telescopes on the ground and in space, scanning the different galactic regions involved in stellar births.

“For the first time we are resolving individual units of star formation over a wide range of locations and environments in a sample that well represents the different types of galaxies,” says Eric Emsellem, an astronomer at ESO in Germany and lead of the VLT-based observations conducted as part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) project. “We can directly observe the gas that gives birth to stars, we see the young stars themselves, and we witness their evolution through various phases.”

Emsellem, who is also affiliated with the U Claude Lyon 1 [Université Claude Bernard Lyon 1] (FR), and his team have now released their latest set of galactic scans, taken with the Multi-Unit Spectroscopic Explorer (MUSE) instrument on ESO’s VLT in the Atacama Desert in Chile. They used MUSE to trace newborn stars and the warm gas around them, which is illuminated and heated up by the stars and acts as a smoking gun of ongoing star formation.

The new MUSE images are now being combined with observations of the same galaxies taken with ALMA and released earlier this year. ALMA, which is also located in Chile, is especially well suited to mapping cold gas clouds — the parts of galaxies that provide the raw material out of which stars form.

By combining MUSE and ALMA images astronomers can examine the galactic regions where star formation is happening, compared to where it is expected to happen, so as to better understand what triggers, boosts or holds back the birth of new stars. The resulting images are stunning, offering a spectacularly colourful insight into stellar nurseries in our neighbouring galaxies.

“There are many mysteries we want to unravel,” says Kathryn Kreckel from the Ruprecht Karl University of Heidelberg [Ruprecht-Karls-Universität Heidelberg](DE) and PHANGS team member. “Are stars more often born in specific regions of their host galaxies — and, if so, why? And after stars are born how does their evolution influence the formation of new generations of stars?”

Astronomers will now be able to answer these questions thanks to the wealth of MUSE and ALMA data the PHANGS team have obtained. MUSE collects spectra — the “bar codes” astronomers scan to unveil the properties and nature of cosmic objects — at every single location within its field of view, thus providing much richer information than traditional instruments. For the PHANGS project, MUSE observed 30 000 nebulae of warm gas and collected about 15 million spectra of different galactic regions. The ALMA observations, on the other hand, allowed astronomers to map around 100 000 cold-gas regions across 90 nearby galaxies, producing an unprecedentedly sharp atlas of stellar nurseries in the close Universe.

In addition to ALMA and MUSE, the PHANGS project also features observations from the NASA/ESA Hubble Space Telescope.

National Aeronautics and Space Administration(US)/European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation] (EU) Hubble Space Telescope

The various observatories were selected to allow the team to scan our galactic neighbours at different wavelengths (visible, near-infrared and radio), with each wavelength range unveiling distinct parts of the observed galaxies. “Their combination allows us to probe the various stages of stellar birth — from the formation of the stellar nurseries to the onset of star formation itself and the final destruction of the nurseries by the newly born stars — in more detail than is possible with individual observations,” says PHANGS team member Francesco Belfiore from INAF-Arcetri in Florence, Italy. “PHANGS is the first time we have been able to assemble such a complete view, taking images sharp enough to see the individual clouds, stars, and nebulae that signify forming stars.”

The work carried out by the PHANGS project will be further honed by upcoming telescopes and instruments, such as NASA’s James Webb Space Telescope.

National Aeronautics Space Agency(USA)/European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU)/ Canadian Space Agency [Agence Spatiale Canadienne](CA) Webb Infrared Space Telescope(US) James Webb Space Telescope annotated. Scheduled for launch in October 2021.

The data obtained in this way will lay further groundwork for observations with ESO’s future Extremely Large Telescope (ELT) [below], which will start operating later this decade and will enable an even more detailed look at the structures of stellar nurseries.

“As amazing as PHANGS is, the resolution of the maps that we produce is just sufficient to identify and separate individual star-forming clouds, but not good enough to see what’s happening inside them in detail,” pointed out Eva Schinnerer, a research group leader at the Max Planck Institute for Astronomy in Germany and principal investigator of the PHANGS project, under which the new observations were conducted. “New observational efforts by our team and others are pushing the boundary in this direction, so we have decades of exciting discoveries ahead of us.”

More information

The international PHANGS team is composed of over 90 scientists ranging from Master students to retirees working at 30 institutions across four continents. The MUSE data reduction working group within PHANGS is being led by Eric Emsellem (European Southern Observatory, Garching, Germany and Centre de Recherche Astrophysique de Lyon, Université de Lyon, ENS de Lyon, Saint-Genis Laval, France) and includes Francesco Belfiore (INAF Osservatorio Astrofisico di Arcetri, Florence, Italy), Guillermo Blanc, Carnegie Observatories, Pasadena, US), Enrico Congiu (Universidad de Chile, Santiago, Chile and Las Campanas Observatory, Carnegie Institution for Science, Atacama Region, Chile), Brent Groves (The University of Western Australia (AU), Perth, Australia), I-Ting Ho (Max Planck Institute for Astronomy, Heidelberg, Germany [MPIA]), Kathryn Kreckel (Heidelberg University, Heidelberg, Germany), Rebecca McElroy (Sydney Institute for Astronomy (SIfA) (AU), Sydney, Australia), Ismael Pessa (MPIA), Patricia Sanchez-Blazquez (Complutense University of Madrid[Universidad Complutense Madrid] Institute of Particle and Cosmos Physics [Instituto de Física de Partículas y Cosmos] (ES), Madrid, Spain), Francesco Santoro (MPIA), Fabian Scheuermann (Heidelberg University, Heidelberg, Germany) and Eva Schinnerer (MPIA).

Go to the ESO public image archive to see a sample of PHANGS images.

See the full article here .

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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

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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

European Southern Observatory(EU) La Silla HELIOS (HARPS Experiment for Light Integrated Over the Sun)

ESO 3.6m telescope & HARPS atCerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

MPG Institute for Astronomy [Max-Planck-Institut für Astronomie](DE) 2.2 meter telescope at/European Southern Observatory(EU) Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

European Southern Observatory(EU)La Silla Observatory 600 km north of Santiago de Chile at an altitude of 2400 metres.

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. [/caption]

European Southern Observatory(EU) VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ),
•KUEYEN (UT2; The Moon ),
•MELIPAL (UT3; The Southern Cross ), and
•YEPUN (UT4; Venus – as evening star).

ESO Very Large Telescope 4 lasers on Yepun (CL)

Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

ESO/NTT NTT at Cerro La Silla , Chile, at an altitude of 2400 metres.

Part of ESO’s Paranal Observatory the VLT Survey Telescope (VISTA) observes the brilliantly clear skies above the Atacama Desert of Chile. It is the largest survey telescope in the world in visible light, with an elevation of 2,635 metres (8,645 ft) above sea level.

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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).

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).

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

ESO Next Generation Transit Survey telescopes, an array of twelve robotic 20-centimetre telescopes at Cerro Paranal,(CL) 2,635 metres (8,645 ft) above sea level.

TAROT telescope at Cerro LaSilla, 2,635 metres (8,645 ft) above sea level.

European Southern Observatory(EU) ExTrA telescopes at erro LaSilla at an altitude of 2400 metres.

A novel gamma ray telescope under construction on Mount Hopkins, Arizona. A large project known as the Čerenkov Telescope Array composed of hundreds of similar telescopes to be situated in the Canary Islands and Chile at, ESO Cerro Paranal site The telescope on Mount Hopkins will be fitted with a prototype high-speed camera, assembled at the. University of Wisconsin–Madison and capable of taking pictures at a billion frames per second. Credit: Vladimir Vassiliev.

European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), The new Test-Bed Telescope 2is housed inside the shiny white dome shown in this picture, at ESO’s LaSilla Facility in Chile. The telescope has now started operations and will assist its northern-hemisphere twin in protecting us from potentially hazardous, near-Earth objects.The domes of ESO’s 0.5 m and the Danish 0.5 m telescopes are visible in the background of this image.Part of the world-wide effort to scan and identify near-Earth objects, the European Space Agency’s Test-Bed Telescope 2 (TBT2), a technology demonstrator hosted at ESO’s La Silla Observatory in Chile, has now started operating. Working alongside its northern-hemisphere partner telescope, TBT2 will keep a close eye on the sky for asteroids that could pose a risk to Earth, testing hardware and software for a future telescope network.

European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) The open dome of The black telescope structure of the‘s Test-Bed Telescope 2 peers out of its open dome in front of the rolling desert landscape. The telescope is located at ESO’s La Silla Observatory, which sits at a 2400 metre altitude in the Chilean Atacama desert.

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

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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.

Nobeyama Millimeter Array Radioheliograph, located near Minamimaki, Nagano at an elevation of 1350m

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.

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.

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.

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).

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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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

From Harvard-Smithsonian Center for Astrophysics (US) via phys.org : “A massive protocluster of merging galaxies in the early universe”

From Harvard-Smithsonian Center for Astrophysics (US)

via

phys.org

June 25, 2021

An artist’s impression of the protocluster of galaxies SPT2349-56, a group of over a dozen interacting galaxies in the early universe. Astronomers have observed the protocluster in optical, infrared, and millimeter radiation, and determined that several member galaxies are “submillimeter galaxies,” among the most luminous, rapidly star-forming galaxies known. Credit: M. Kornmesser/European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU) (CL)

Submillimeter galaxies (SMGs) are a class of the most luminous, distant, and rapidly star-forming galaxies known and can shine brighter than a trillion Suns (about one hundred times more luminous in total than the Milky Way). They are generally hard to detect in the visible, however, because most of their ultraviloet and optical light is absorbed by dust which in turn is heated and radiates at submillimeter wavelengths—the reason they are called submillimeter galaxies. The power source for these galaxies is thought to be high rates of star formation, as much as one thousand stars per year (in the Milky Way, the rate is more like one star per year). SMGs typically date from the early universe; they are so distant that their light has been traveling for over ten billion years, more than 70% of the lifetime of the universe, from the epoch about three billion years after the big bang. Because it takes time for them to have evolved, astronomers think that even a billion years earlier they probably were actively making stars and influencing their environments, but very little is known about this phase of their evolution.

SMGs have recently been identified in galaxy protoclusters, groups of dozens of galaxies in the universe when it was less than a few billion years old. Observing massive SMGs in these distant protoclusters provides crucial details for understanding both their early evolution and that of the larger structures to which they belong. CfA astronomers Emily Pass and Matt Ashby were members of a team that used infrared and optical data from the Spitzer IRAC and Gemini-South instruments, respectively, to study a previosly identified protocluster, SPT2349-56, in the era only 1.4 billion years after the big bang. The protocluster was spotted by the South Pole Telescope millimeter wavelengths and then observed in more detail with Spitzer, Gemini, and the ALMA submillimeter array.

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

National Aeronautics and Space Administration(US) Spitzer Infrared Space Telescope no longer in service. Launched in 2003 and retired on 30 January 2020.

NSF NOIRLab(US) NOAO(US) Gemini South telescope (US) Cerro Tololo Inter-American Observatory(CL) campus near La Serena, Chile, at an altitude of 7200 feet on the summit of Cerro Pachon.

NOIRLab(US)NOAO Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

The protocluster contains a remarkable concentration of fourteen SMGs, nine of which were detected by these optical and infrared observations. The astronomers were then able to estimate the stellar masses, ages, and gas content in these SMGs, as well as their star formation histories, a remarkable acheievment for such distant objects. Among other properties of the protocluster, the scientists deduce that its total mass is about one trillion solar-masses, and its galaxies are making stars in a manner similar to star formation processes in the current universe. They also conclude that the whole ensemble is probably in the midst of a colossal merger.

Science paper:
MNRAS

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The Harvard-Smithsonian Center for Astrophysics (US) combines the resources and research facilities of the Harvard College Observatory(US) and the Smithsonian Astrophysical Observatory(US) under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory(US) is a bureau of the Smithsonian Institution(US), founded in 1890. The Harvard College Observatory, founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University(US), and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

Founded in 1973 and headquartered in Cambridge, Massachusetts, the CfA leads a broad program of research in astronomy, astrophysics, Earth and space sciences, as well as science education. The CfA either leads or participates in the development and operations of more than fifteen ground- and space-based astronomical research observatories across the electromagnetic spectrum, including the forthcoming Giant Magellan Telescope(CL) and the Chandra X-ray Observatory(US), one of NASA’s Great Observatories.

Giant Magellan Telescope(CL) 21 meters, to be at the Carnegie Institution for Science’s(US) NSF (US) NOIRLab(US) NOAO(US) Las Campanas Observatory(CL) some 115 km (71 mi) north-northeast of La Serena, Chile, over 2,500 m (8,200 ft) high.

National Aeronautics and Space Administration(US) Chandra X-ray telescope(US).

Hosting more than 850 scientists, engineers, and support staff, the CfA is among the largest astronomical research institutes in the world. Its projects have included Nobel Prize-winning advances in cosmology and high energy astrophysics, the discovery of many exoplanets, and the first image of a black hole. The CfA also serves a major role in the global astrophysics research community: the CfA’s Astrophysics Data System(ADS)(US), for example, has been universally adopted as the world’s online database of astronomy and physics papers. Known for most of its history as the “Harvard-Smithsonian Center for Astrophysics”, the CfA rebranded in 2018 to its current name in an effort to reflect its unique status as a joint collaboration between Harvard University and the Smithsonian Institution. The CfA’s current Director (since 2004) is Charles R. Alcock, who succeeds Irwin I. Shapiro (Director from 1982 to 2004) and George B. Field (Director from 1973 to 1982).

The Center for Astrophysics | Harvard & Smithsonian is not formally an independent legal organization, but rather an institutional entity operated under a Memorandum of Understanding between Harvard University and the Smithsonian Institution. This collaboration was formalized on July 1, 1973, with the goal of coordinating the related research activities of the Harvard College Observatory (HCO) and the Smithsonian Astrophysical Observatory (SAO) under the leadership of a single Director, and housed within the same complex of buildings on the Harvard campus in Cambridge, Massachusetts. The CfA’s history is therefore also that of the two fully independent organizations that comprise it. With a combined lifetime of more than 300 years, HCO and SAO have been host to major milestones in astronomical history that predate the CfA’s founding.

History of the Smithsonian Astrophysical Observatory (SAO)

Samuel Pierpont Langley, the third Secretary of the Smithsonian, founded the Smithsonian Astrophysical Observatory on the south yard of the Smithsonian Castle (on the U.S. National Mall) on March 1,1890. The Astrophysical Observatory’s initial, primary purpose was to “record the amount and character of the Sun’s heat”. Charles Greeley Abbot was named SAO’s first director, and the observatory operated solar telescopes to take daily measurements of the Sun’s intensity in different regions of the optical electromagnetic spectrum. In doing so, the observatory enabled Abbot to make critical refinements to the Solar constant, as well as to serendipitously discover Solar variability. It is likely that SAO’s early history as a solar observatory was part of the inspiration behind the Smithsonian’s “sunburst” logo, designed in 1965 by Crimilda Pontes.

In 1955, the scientific headquarters of SAO moved from Washington, D.C. to Cambridge, Massachusetts to affiliate with the Harvard College Observatory (HCO). Fred Lawrence Whipple, then the chairman of the Harvard Astronomy Department, was named the new director of SAO. The collaborative relationship between SAO and HCO therefore predates the official creation of the CfA by 18 years. SAO’s move to Harvard’s campus also resulted in a rapid expansion of its research program. Following the launch of Sputnik (the world’s first human-made satellite) in 1957, SAO accepted a national challenge to create a worldwide satellite-tracking network, collaborating with the United States Air Force on Project Space Track.

With the creation of National Aeronautics and Space Administration(US) the following year and throughout the space race, SAO led major efforts in the development of orbiting observatories and large ground-based telescopes, laboratory and theoretical astrophysics, as well as the application of computers to astrophysical problems.

History of Harvard College Observatory (HCO)

Partly in response to renewed public interest in astronomy following the 1835 return of Halley’s Comet, the Harvard College Observatory was founded in 1839, when the Harvard Corporation appointed William Cranch Bond as an “Astronomical Observer to the University”. For its first four years of operation, the observatory was situated at the Dana-Palmer House (where Bond also resided) near Harvard Yard, and consisted of little more than three small telescopes and an astronomical clock. In his 1840 book recounting the history of the college, then Harvard President Josiah Quincy III noted that “…there is wanted a reflecting telescope equatorially mounted…”. This telescope, the 15-inch “Great Refractor”, opened seven years later (in 1847) at the top of Observatory Hill in Cambridge (where it still exists today, housed in the oldest of the CfA’s complex of buildings). The telescope was the largest in the United States from 1847 until 1867. William Bond and pioneer photographer John Adams Whipple used the Great Refractor to produce the first clear Daguerrotypes of the Moon (winning them an award at the 1851 Great Exhibition in London). Bond and his son, George Phillips Bond (the second Director of HCO), used it to discover Saturn’s 8th moon, Hyperion (which was also independently discovered by William Lassell).

Under the directorship of Edward Charles Pickering from 1877 to 1919, the observatory became the world’s major producer of stellar spectra and magnitudes, established an observing station in Peru, and applied mass-production methods to the analysis of data. It was during this time that HCO became host to a series of major discoveries in astronomical history, powered by the Observatory’s so-called “Computers” (women hired by Pickering as skilled workers to process astronomical data). These “Computers” included Williamina Fleming; Annie Jump Cannon; Henrietta Swan Leavitt; Florence Cushman; and Antonia Maury, all widely recognized today as major figures in scientific history. Henrietta Swan Leavitt, for example, discovered the so-called period-luminosity relation for Classical Cepheid variable stars, establishing the first major “standard candle” with which to measure the distance to galaxies. Now called “Leavitt’s Law”, the discovery is regarded as one of the most foundational and important in the history of astronomy; astronomers like Edwin Hubble, for example, would later use Leavitt’s Law to establish that the Universe is expanding, the primary piece of evidence for the Big Bang model.

Upon Pickering’s retirement in 1921, the Directorship of HCO fell to Harlow Shapley (a major participant in the so-called “Great Debate” of 1920). This era of the observatory was made famous by the work of Cecelia Payne-Gaposchkin, who became the first woman to earn a Ph.D. in astronomy from Radcliffe College (a short walk from the Observatory). Payne-Gapochkin’s 1925 thesis proposed that stars were composed primarily of hydrogen and helium, an idea thought ridiculous at the time. Between Shapley’s tenure and the formation of the CfA, the observatory was directed by Donald H. Menzel and then Leo Goldberg, both of whom maintained widely recognized programs in solar and stellar astrophysics. Menzel played a major role in encouraging the Smithsonian Astrophysical Observatory to move to Cambridge and collaborate more closely with HCO.

Joint history as the Center for Astrophysics (CfA)

The collaborative foundation for what would ultimately give rise to the Center for Astrophysics began with SAO’s move to Cambridge in 1955. Fred Whipple, who was already chair of the Harvard Astronomy Department (housed within HCO since 1931), was named SAO’s new director at the start of this new era; an early test of the model for a unified Directorship across HCO and SAO. The following 18 years would see the two independent entities merge ever closer together, operating effectively (but informally) as one large research center.

This joint relationship was formalized as the new Harvard–Smithsonian Center for Astrophysics on July 1, 1973. George B. Field, then affiliated with UC Berkeley(US), was appointed as its first Director. That same year, a new astronomical journal, the CfA Preprint Series was created, and a CfA/SAO instrument flying aboard Skylab discovered coronal holes on the Sun. The founding of the CfA also coincided with the birth of X-ray astronomy as a new, major field that was largely dominated by CfA scientists in its early years. Riccardo Giacconi, regarded as the “father of X-ray astronomy”, founded the High Energy Astrophysics Division within the new CfA by moving most of his research group (then at American Sciences and Engineering) to SAO in 1973. That group would later go on to launch the Einstein Observatory (the first imaging X-ray telescope) in 1976, and ultimately lead the proposals and development of what would become the Chandra X-ray Observatory. Chandra, the second of NASA’s Great Observatories and still the most powerful X-ray telescope in history, continues operations today as part of the CfA’s Chandra X-ray Center. Giacconi would later win the 2002 Nobel Prize in Physics for his foundational work in X-ray astronomy.

Shortly after the launch of the Einstein Observatory, the CfA’s Steven Weinberg won the 1979 Nobel Prize in Physics for his work on electroweak unification. The following decade saw the start of the landmark CfA Redshift Survey (the first attempt to map the large scale structure of the Universe), as well as the release of the Field Report, a highly influential Astronomy & Astrophysics Decadal Survey chaired by the outgoing CfA Director George Field. He would be replaced in 1982 by Irwin Shapiro, who during his tenure as Director (1982 to 2004) oversaw the expansion of the CfA’s observing facilities around the world.

Harvard Smithsonian Center for Astrophysics(US) Fred Lawrence Whipple Observatory(US) located near Amado, Arizona on the slopes of Mount Hopkins, Altitude 2,606 m (8,550 ft)

European Space Agency [Agence spatiale européenne](EU)/National Aeronautics and Space Administration(US) SOHO satellite. Launched in 1995.

National Aeronautics Space Agency(US) NASA Kepler Space Telescope (US)

CfA-led discoveries throughout this period include canonical work on Supernova 1987A, the “CfA2 Great Wall” (then the largest known coherent structure in the Universe), the best-yet evidence for supermassive black holes, and the first convincing evidence for an extrasolar planet.

The 1990s also saw the CfA unwittingly play a major role in the history of computer science and the internet: in 1990, SAO developed SAOImage, one of the world’s first X11-based applications made publicly available (its successor, DS9, remains the most widely used astronomical FITS image viewer worldwide). During this time, scientists at the CfA also began work on what would become the Astrophysics Data System (ADS), one of the world’s first online databases of research papers. By 1993, the ADS was running the first routine transatlantic queries between databases, a foundational aspect of the internet today.

The CfA Today

Research at the CfA

Charles Alcock, known for a number of major works related to massive compact halo objects, was named the third director of the CfA in 2004. Today Alcock overseas one of the largest and most productive astronomical institutes in the world, with more than 850 staff and an annual budget in excess of $100M. The Harvard Department of Astronomy, housed within the CfA, maintains a continual complement of approximately 60 Ph.D. students, more than 100 postdoctoral researchers, and roughly 25 undergraduate majors in astronomy and astrophysics from Harvard College. SAO, meanwhile, hosts a long-running and highly rated REU Summer Intern program as well as many visiting graduate students. The CfA estimates that roughly 10% of the professional astrophysics community in the United States spent at least a portion of their career or education there.

The CfA is either a lead or major partner in the operations of the Fred Lawrence Whipple Observatory, the Submillimeter Array, MMT Observatory, the South Pole Telescope, VERITAS, and a number of other smaller ground-based telescopes. The CfA’s 2019-2024 Strategic Plan includes the construction of the Giant Magellan Telescope as a driving priority for the Center.

CFA Harvard Smithsonian Submillimeter Array on MaunaKea, Hawaii, USA, Altitude 4,205 m (13,796 ft).

[caption id="attachment_31175" align="alignnone" width="632"] South Pole Telescope SPTPOL. The SPT collaboration is made up of over a dozen (mostly North American) institutions, including The University of Chicago (US); The University of California Berkeley (US); Case Western Reserve University (US); Harvard/Smithsonian Astrophysical Observatory (US); The University of Colorado, Boulder; McGill(CA) University, The University of Illinois, Urbana-Champaign;The University of California, Davis; Ludwig Maximilians Universität München(DE); DOE’s Argonne National Laboratory; and The National Institute for Standards and Technology. The University of California, Davis; Ludwig Maximilians Universität München(DE); DOE’s Argonne National Laboratory; and The National Institute for Standards and Technology. It is funded by the National Science Foundation(US).

Along with the Chandra X-ray Observatory, the CfA plays a central role in a number of space-based observing facilities, including the recently launched Parker Solar Probe, Kepler Space Telescope, the Solar Dynamics Observatory (SDO), and HINODE. The CfA, via the Smithsonian Astrophysical Observatory, recently played a major role in the Lynx X-ray Observatory, a NASA-Funded Large Mission Concept Study commissioned as part of the 2020 Decadal Survey on Astronomy and Astrophysics (“Astro2020”). If launched, Lynx would be the most powerful X-ray observatory constructed to date, enabling order-of-magnitude advances in capability over Chandra.

NASA Parker Solar Probe Plus named to honor Pioneering Physicist Eugene Parker.

National Aeronautics and Space Administration(US)Solar Dynamics Observatory(US)

Japan Aerospace Exploration Agency (JAXA) (国立研究開発法人宇宙航空研究開発機構] (JP)/National Aeronautics and Space Administration(US) HINODE spacecraft.

SAO is one of the 13 stakeholder institutes for the Event Horizon Telescope Board, and the CfA hosts its Array Operations Center. In 2019, the project revealed the first direct image of a black hole.

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 The Event Horizon Telescope Collaboration released on 10 April 2019 via National Science Foundation(US).

The result is widely regarded as a triumph not only of observational radio astronomy, but of its intersection with theoretical astrophysics. Union of the observational and theoretical subfields of astrophysics has been a major focus of the CfA since its founding.

In 2018, the CfA rebranded, changing its official name to the “Center for Astrophysics | Harvard & Smithsonian” in an effort to reflect its unique status as a joint collaboration between Harvard University and the Smithsonian Institution. Today, the CfA receives roughly 70% of its funding from NASA, 22% from Smithsonian federal funds, and 4% from the National Science Foundation. The remaining 4% comes from contributors including the United States Department of Energy, the Annenberg Foundation, as well as other gifts and endowments.

From ALMA(CL) : “Mind the Gap- Scientists Use Stellar Mass to Link Exoplanets to Planet-Forming Disks”

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

From ALMA(CL)/ European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP)

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

All general references:
ALMA Observatory (CL)
European Southern Observatory(EU)
National Astronomical Observatory of Japan(JP)
National Radio Astronomy Observatory(US)

Protoplanetary disks are classified into three main categories: transition, ring, or extended. These false-color images from the Atacama Large Millimeter/submillimeter Array (ALMA) show these classifications in stark contrast. On left: the ring disk of RU Lup is characterized by narrow gaps thought to be carved by giant planets with masses ranging between a Neptune mass and a Jupiter mass. Middle: the transition disk of J1604.3-2130 is characterized by a large inner cavity thought to be carved by planets more massive than Jupiter, also known as Super-Jovian planets. On right: the compact disk of Sz104 is believed not to contain giant planets, as it lacks the telltale gaps and cavities associated with the presence of giant planets. Credit: S. Dagnello (NRAO) ALMA (ESO/NAOJ/NRAO).

Using data for more than 500 young stars observed with the Atacama Large Millimeter/submillimeter Array (ALMA), scientists have uncovered a direct link between protoplanetary disk structures—the planet-forming disks that surround stars—and planet demographics. The survey proves that higher mass stars are more likely to be surrounded by disks with “gaps” in them and that these gaps directly correlate to the high occurrence of observed giant exoplanets around such stars. These results provide scientists with a window back through time, allowing them to predict what exoplanetary systems looked like through each stage of their formation.

“We found a strong correlation between gaps in protoplanetary disks and stellar mass, which can be linked to the presence of large, gaseous exoplanets,” said Nienke van der Marel, a Banting fellow in the Department of Physics and Astronomy at the University of Victoria (CA) in British Columbia (CA), and the primary author on the research. “Higher mass stars have relatively more disks with gaps than lower mass stars, consistent with the already known correlations in exoplanets, where higher mass stars more often host gas-giant exoplanets. These correlations directly tell us that gaps in planet-forming disks are most likely caused by giant planets of Neptune mass and above.”

Gaps in protoplanetary disks have long been considered as overall evidence of planet formation. However, there has been some skepticism due to the observed orbital distance between exoplanets and their stars. “One of the primary reasons that scientists have been skeptical about the link between gaps and planets before is that exoplanets at wide orbits of tens of astronomical units are rare. However, exoplanets at smaller orbits, between one and ten astronomical units, are much more common,” said Gijs Mulders, assistant professor of astronomy at Universidad Adolfo Ibáñez in Santiago, Chile, and co-author on the research. “We believe that planets that clear the gaps will migrate inwards later on.”

The new study is the first to show that the number of gapped disks in these regions matches the number of giant exoplanets in a star system. “Previous studies indicated that there were many more gapped disks than detected giant exoplanets,” said Mulders. “Our study shows that there are enough exoplanets to explain the observed frequency of the gapped disks at different stellar masses.”

The correlation also applies to star systems with low-mass stars, where scientists are more likely to find massive rocky exoplanets, also known as Super-Earths. Van der Marel, who will become an assistant professor at Leiden University in the Netherlands beginning September 2021 said, “Lower mass stars have more rocky Super-Earths—between an Earth mass and a Neptune mass. Disks without gaps, which are more compact, lead to the formation of Super-Earths.”

This link between stellar mass and planetary demographics could help scientists identify which stars to target in the search for rocky planets throughout the Milky Way. “This new understanding of stellar mass dependencies will help to guide the search for small, rocky planets like Earth in the solar neighborhood,” said Mulders, who is also a part of the NASA-funded Alien Earths team. “We can use the stellar mass to connect the planet-forming disks around young stars to exoplanets around mature stars. When an exoplanet is detected, the planet-forming material is usually gone. So the stellar mass is a ‘tag’ that tells us what the planet-forming environment might have looked like for these exoplanets.”

And what it all comes down to is dust. “An important element of planet formation is the influence of dust evolution,” said van der Marel. “Without giant planets, dust will always drift inwards, creating the optimal conditions for the formation of smaller, rocky planets close to the star.”

The current research was conducted using data for more than 500 objects observed in prior studies using ALMA’s high-resolution Band 6 and Band 7 antennas. At present, ALMA is the only telescope that can image the distribution of millimeter-dust at high enough angular resolution to resolve the dust disks and reveal its substructure, or lack thereof. “Over the past five years, ALMA has produced many snapshot surveys of nearby star-forming regions resulting in hundreds of measurements of disk dust mass, size, and morphology,” said van der Marel. “The large number of observed disk properties has allowed us to make a statistical comparison of protoplanetary disks to the thousands of discovered exoplanets. This is the first time that a stellar mass dependency of gapped disks and compact disks has been successfully demonstrated using the ALMA telescope.”

“Our new findings link the beautiful gap structures in disks observed with ALMA directly to the properties of the thousands of exoplanets detected by the NASA Kepler mission and other exoplanet surveys,” said Mulders. “Exoplanets and their formation help us place the origins of the Earth and the Solar System in the context of what we see happening around other stars.”

Additional Information

The results of this research appeared as “A stellar mass dependence of structured disks: a possible link with exoplanet demographics” by N. van der Marel et al. in The Astrophysical Journal.

See the full article here .

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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 European Southern Observatory(EU), on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (US) 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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

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”

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

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.

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).

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.

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.

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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins

From ALMA [The Atacama Large Millimeter/submillimeter Array] (CL) : “ALMA Discovers Earliest Gigantic Black Hole Storm”

European Southern Observatory/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) 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

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

11 June, 2021

Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) discovered a titanic galactic wind driven by a supermassive black hole 13.1 billion years ago. This is the earliest-yet-observed example of such wind to date and is a telltale sign that huge black holes have a profound effect on the growth of galaxies from the very early history of the Universe.

Artist’s impression of a galactic wind driven by a supermassive black hole located in the center of a galaxy. The intense energy emanating from the black hole creates a galaxy-scale flow of gas that blows away the interstellar matter that is the material for forming stars. Credit: ALMA (ESO/NAOJ/NRAO)

ALMA image of the distant galaxy J1243+0100 hosting a supermassive black hole in its center. The distribution of the quiet gas in the galaxy is shown in yellow, and the distribution of high-speed galactic wind is shown in blue. The wind is located in the galaxy center, which indicates the supermassive black hole drives the wind. Credit: ALMA (ESO/NAOJ/NRAO), Izumi et al.

At the center of many large galaxies hides a supermassive black hole that is millions to billions of times more massive than the Sun. Interestingly, the mass of the black hole is roughly proportional to the mass of the central region (bulge) of the galaxy in the nearby Universe. At first glance, this may seem obvious, but it is actually very strange. The reason is that the sizes of galaxies and black holes differ by about ten orders of magnitude. Based on this proportional relationship between the masses of two objects that are so different in size, astronomers believe that galaxies and black holes grew and evolved together (coevolution) through some kind of physical interaction.

A galactic wind can provide this kind of physical interaction between black holes and galaxies. A supermassive black hole swallows a large amount of matter. As that matter begins to move at high speed due to the black hole’s gravity, it emits intense energy, which can push the surrounding matter outward. This is how the galactic wind is created.

“The question is when did galactic winds come into existence in the Universe?” says Takuma Izumi, the lead author of the research paper and a researcher at the National Astronomical Observatory of Japan (NAOJ). “This is an important question because it is related to an important problem in astronomy: How did galaxies and supermassive black holes coevolve?”

The research team first used NAOJ’s Subaru Telescope to search for supermassive black holes.

NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level

Thanks to its wide-field observation capability, they found more than 100 galaxies with supermassive black holes in the Universe more than 13 billion years ago [1].

Then, the research team utilized ALMA’s high sensitivity to investigate the gas motion in the host galaxies of the black holes. ALMA observed a galaxy HSC J124353.93+010038.5 (hereafter J1243+0100), discovered by the Subaru Telescope, and captured radio waves emitted by the dust and carbon ions in the galaxy [2].

Detailed analysis of the ALMA data revealed that there is a high-speed gas flow moving at 500 km per second in J1243+0100. This gas flow has enough energy to push away the stellar material in the galaxy and stop the star formation activity. The gas flow found in this study is truly a galactic wind, and it is the oldest observed example of a galaxy with a huge wind of galactic size. The previous record-holder was a galaxy about 13 billion years ago, so this observation pushes the start back another 100 million years.

The team also measured the motion of the quiet gas in J1243+0100 and estimated the mass of the galaxy’s bulge, based on its gravitational balance, to be about 30 billion times that of the Sun. The mass of the galaxy’s supermassive black hole, estimated by another method, was about 1% of that. The mass ratio of the bulge to the supermassive black hole in this galaxy is almost identical to the mass ratio of black holes to galaxies in the modern Universe. This implies that the coevolution of supermassive black holes and galaxies has been occurring since less than a billion years after the birth of the Universe.

“Our observations support recent high-precision computer simulations which have predicted that coevolutionary relationships were in place even at about 13 billion years ago,” comments Izumi. “We are planning to observe a large number of such objects in the future and hope to clarify whether or not the primordial coevolution seen in this object is an accurate picture of the general Universe at that time.”
Notes

[1] For more information, please see the Subaru Telescope press release issued on March 13, 2019, Astronomers Discover 83 Supermassive Black Holes in the Early Universe. The number of galaxies with supermassive black holes discovered was 83 at the time of this announcement, but the number of discoveries has now increased to over 100.

[2] The redshift of this object is z=7.07. Using the cosmological parameters measured with Planck (H0=67.3km/s/Mpc, Ωm=0.315, Λ=0.685: Planck 2013 Results), we can calculate the distance to the object to be 13.1 billion light-years. (Please refer to Expressing the distance to remote objects for the details.)

These observation results are presented as Takuma Izumi et al. Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). XIII. Large-scale Feedback and Star Formation in a Low-Luminosity Quasar at z = 7.07, in The Astrophysical Journal on June 14, 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.

ALMA is a time machine!

ALMA-In Search of our Cosmic Origins