From ALMA: “ALMA Discover Early Protostar With a Warped Disk”

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

From ALMA

31 December, 2018

Jens Wilkinson
RIKEN Global Communications
Japan
Phone: +81-(0)48-462-1225
Email: pr@riken.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

Calum Turner
ESO Assistant Public Information Officer
Garching bei München, Germany
Phone: +49 89 3200 6670
Email: calum.turner@eso.org

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu

Artist’s impression of a warped disk around a protostar. ALMA observed the protostar IRAS04368+2557 in the dark cloud L1527 and discovered that the protostar has a disk with two misaligned parts. Credit: RIKEN

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, researchers have observed, for the first time, a warped disk around an infant protostar that formed just several tens of thousands of years ago. This implies that the misalignment of planetary orbits in many planetary systems, including our own, may be caused by distortions in the planet-forming disk early in their existence.

The planets in the Solar System orbit the Sun in planes that are at most about seven degrees offset from the equator of the Sun itself. It has been known for some time that many extrasolar systems have planets that are not lined up in a single plane or with the equator of the star. One explanation for this is that some of the planets might have been affected by collisions with other objects in the system or by stars passing by the system, ejecting them from the initial plane.

However, the possibility remained that the formation of planets out of the normal plane was actually caused by a warping of the star-forming cloud out of which the planets were born. Recently, images of protoplanetary disks, rotating disks where planets form around a star, have in fact showed such warping. But it was still unclear how early this happened.

In the latest findings, published in Nature, the group from the and Chiba University in Japan have discovered that L1527; an infant protostar still embedded within a cloud, has a disk that has two parts, an inner one rotating in one plane, and an outer one in a different plane. The disk is very young and still growing. L1527, which is about 450 light years away in the Taurus Molecular Cloud, is a good object for study as it has a disk that is nearly edge-on to our view.

According to Nami Sakai, who led the research group, “this observation shows that it is conceivable that the misalignment of planetary orbits can be caused by a warp structure formed in the earliest stages of planetary formation. We will have to investigate more systems to find out if this is a common phenomenon or not.”

The remaining question is what caused the warping of the disk. Sakai suggests two reasonable explanations. “One possibility,” she says, “is that irregularities in the flow of gas and dust in the protostellar cloud are still preserved and manifest themselves as the warped disk. A second possibility is that the magnetic field of the protostar is in a different plane from the rotational plane of the disk, and that the inner disk is being pulled into a different plane from the rest of the disk by the magnetic field.” She says they plan further work to determine which is responsible for the warping of the disk.

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

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

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From Perimeter Institute: “New fellowships to fuel fundamental physics with radio telescopes in Canada”

From Perimeter Institute

December 20, 2018

Perimeter Institute and Canada’s National Research Council have created a pair of postdoctoral fellowships for exceptional emerging radio astronomers.

As radio astronomy enters a transformative new era, Perimeter Institute and Canada’s National Research Council (NRC) have launched two new fellowships to accelerate the research of young scientists conducting theory, data analysis, or instrument development.

The new initiative is a collaboration between Perimeter and NRC’s Dominion Radio Astrophysical Observatory (DRAO), the site of Canada’s revolutionary Canadian Hydrogen Intensity Mapping Experiment (CHIME) Telescope.

CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia, the University of Toronto, McGill University, Yale and the National Research Council in British Columbia, at the Dominion Radio Astrophysical Observatory in Penticton,British Columbia

Instruments like CHIME and forthcoming experiments possess unprecedented statistical power, promising to open new windows into fundamental physics questions, including dark matter, gravity, and neutrinos. These instruments will be used to tackle new challenges in data analysis and high-performance computing, and will help scientists resolve deep astronomical puzzles, such as the origin of fast radio bursts (FRBs).

The Perimeter-DRAO partnership will bring together theorists, data analysts, and instrumentalists at the leading edge of this very exciting field.

One of the postdoctoral fellows will be based at the DRAO, with the other at Perimeter Institute; each will be encouraged to spend time at the other institution to deepen the partnership and strengthen the connections between the institutions.

Perimeter Institute is part of a number of radio astronomy collaborations, including CHIME/FRB, HIRAX (Hydrogen Intensity and Real-time Analysis Experiment), and the EHT (Event Horizon Telescope), among others.

SKA HIRAX prototype dishes at Hartebeesthoek Astronomy Observatory near Johannesburg.

EHT map

EHT APEX, IRAM, G. Narayanan, J. McMahon, JCMT/JAC, S. Hostler, D. Harvey, ESO/C. Malin

Perimeter researchers associated with these initiatives include Avery Broderick, Ue-Li Pen, Will Percival, Daniel Siegel, Kendrick Smith, and Neil Turok.

In addition to hosting CHIME in British Columbia and several other radio telescopes, DRAO features laboratories and specialized equipment for the design and construction of all aspects of radio-frequency instrumentation, from highly sensitive antennae and receiver systems to high-speed digital signal processing hardware and software. This national facility is home to astronomers, astrophysicists, engineers, and technologists, as well as visiting researchers and students from universities and astronomical observatories around the world.

The deadline to apply for the fellowships is January 31, 2019. Find more information and apply here.

See the full article here .

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Please help promote STEM in your local schools.

Stem Education Coalition

About Perimeter
Perimeter Institute is the world’s largest research hub devoted to theoretical physics. The independent Institute was founded in 1999 to foster breakthroughs in the fundamental understanding of our universe, from the smallest particles to the entire cosmos. Research at Perimeter is motivated by the understanding that fundamental science advances human knowledge and catalyzes innovation, and that today’s theoretical physics is tomorrow’s technology. Located in the Region of Waterloo, the not-for-profit Institute is a unique public-private endeavour, including the Governments of Ontario and Canada, that enables cutting-edge research, trains the next generation of scientific pioneers, and shares the power of physics through award-winning educational outreach and public engagement.

From ALMA: “Fragmenting Disk Gives Birth to Binary Star ‘Odd Couple’”

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

From ALMA

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered that two young stars forming from the same swirling protoplanetary disk may be twins — in the sense that they came from the same parent cloud of star-forming material. Beyond that, however, they have shockingly little in common.

The main, central star of this system, which is located approximately 11,000 light-years from Earth, is truly colossal — a full 40 times more massive than the Sun. The other star, which ALMA recently discovered just beyond the central star’s disk, is a relatively puny one-eightieth (1/80) that mass.

Their striking difference in size suggests that they formed by following two very different paths. The more massive star took the more traditional route by collapsing under gravity out of a dense “core” of gas. The smaller one likely followed the road less traveled by – at least for stars – by accumulating mass from a portion of the disk that “fragmented” away as it matured, a process that may have more in common with the birth of gas-giant planets.

“Astronomers have known for a long time that most massive stars orbit one or more other stars as partners in a compact system, but how they got there has been a topic of conjecture,” said Crystal Brogan, an astronomer with the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, and a co-author on the study. “With ALMA, we now have evidence that the disk of gas and dust that encompasses and feeds a growing massive star also produces fragments at early stages that can form a secondary star.”

The main object, known as MM 1a, is a previously identified young massive star surrounded by a rotating disk of gas and dust. A faint protostellar companion to this object, MM 1b, was newly detected by ALMA just outside the MM 1a protoplanetary disk. The team believes this is one of the first examples of a fragmented disk to be detected around a massive young star.

“This ALMA observation opens new questions, such as ‘Does the secondary star also have a disk?’ and ‘How fast can the secondary star grow?’ The amazing thing about ALMA is that we have not yet used its full capabilities in this area, which will someday allow us to answer these new questions,” said co-author Todd Hunter, who is also with the NRAO in Charlottesville.

Stars form within large clouds of gas and dust in interstellar space. When these clouds collapse under gravity, they begin to rotate faster, forming a disk around them.

“In low-mass stars like our Sun, it is in these disks that planets can form,” said John Ilee, an astronomer at Leeds University in England and lead author on the study. “In this case, the star and disk we have observed are so massive that, rather than witnessing a planet forming in the disk, we are seeing another star being born.”

By observing the millimeter wavelength light naturally emitted by the dust, and subtle shifts in the frequency of light emitted by the gas, the researchers were able to calculate the mass of MM 1a and MM 1b.

Their work is published in The Astrophysical Journal Letters.

“Many older massive stars are found with nearby companions,” added Ilee. “But binary stars are often very equal in mass, and so likely formed together as siblings. Finding a young binary system with a mass ratio of 80-to-1 is very unusual and suggests an entirely different formation process for both objects.”

The favored formation process for MM 1b occurs in the outer regions of cold, massive disks. These “gravitationally unstable” disks are unable to hold themselves up against the pull of their own gravity, collapsing into one – or more – fragments.

The researchers note that newly discovered young star MM 1b could also be surrounded by its own circumstellar disk, which may have the potential to form planets of its own – but it will need to be quick. “Stars as massive as MM 1a only live for around a million years before exploding as powerful supernovae, so while MM 1b may have the potential to form its own planetary system in the future, it won’t be around for long,” Ilee concluded.

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), 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.

From ALMA: “ALMA Confirms Comets Forge Organic Molecules in Their Dusty Atmospheres”

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

From ALMA

7 August, 2014 [Retrieved from the ALMA web site]

Valeria Foncea
Education and Public Outreach Officer
Joint ALMA Observatory
Santiago, Chile
Tel: +56 2 467 6258
Cell: +56 9 75871963
Email: vfoncea@alma.cl

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory
Charlottesville, Virginia, USA
Tel: +1 434 296 0314
Cell: +1 434.242.9559
E-mail: cblue@nrao.edu

Masaaki Hiramatsu
Education and Public Outreach Officer, NAOJ Chile
Observatory Tokyo, Japan
Tel: +81 422 34 3630
E-mail: hiramatsu.masaaki@nao.ac.jp

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

Fig. 1: Approximate location of Comet ISON in our Solar System at the time of the ALMA observations. Credit: B. Saxton (NRAO/AUI/NSF); NASA/ESA Hubble; M. Cordiner, NASA, et al.

An international team of scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) has made incredible 3D images of the ghostly atmospheres surrounding comets ISON and Lemmon. These new observations provided important insights into how and where comets forge new chemicals, including intriguing organic compounds.

Comets contain some of the oldest and most pristine materials in our Solar System. Understanding their unique chemistry could reveal much about the birth of our planet and the origin of organic compounds that are the building blocks of life. ALMA’s high-resolution observations provided a tantalizing 3D perspective of the distribution of the molecules within these two cometary atmospheres, or comas.

“We achieved truly first-of-a-kind mapping of important molecules that help us understand the nature of comets,” said team leader Martin Cordiner, a Catholic University of America astrochemist working at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

The critical 3D component of the ALMA observations was made by combining high-resolution, two-dimensional images of the comets with high-resolution spectra obtained from three important organic molecules – hydrogen cyanide (HCN), hydrogen isocyanide (HNC), and formaldehyde (H2CO). These spectra were taken at every point in each image. They identified not only the molecules present but also their velocities, which provided the third dimension, indicating the depths of the cometary atmospheres.

The new results revealed that HCN gas flows outward from the nucleus quite evenly in all directions, whereas HNC is concentrated in clumps and jets. ALMA’s exquisite resolution could clearly resolve these clumps moving into different regions of the cometary comas on a day-to-day and even hour-to-hour basis. These distinctive patterns confirm that the HNC and H2CO molecules actually form within the coma and provide new evidence that HNC may be produced by the breakdown of large molecules or organic dust.

“Understanding organic dust is important, because such materials are more resistant to destruction during atmospheric entry, and some could have been delivered intact to the early Earth, thereby fueling the emergence of life,” said Michael Mumma, director of the Goddard Center for Astrobiology and a co-author on the study. “These observations open a new window on this poorly known component of cometary organics.”

“So, not only does ALMA let us identify individual molecules in the coma, it also gives us the ability to map their locations with great sensitivity,” said Anthony Remijan, an astronomer with the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, and a study co-author.

The observations, published in The Astrophysical Journal Letters, were also significant because modest comets like Lemmon and ISON contain relatively low concentrations of these crucial molecules, making them difficult to probe in depth with Earth-based telescopes. The few comprehensive studies of this kind so far have been conducted on extremely bright comets, such as Hale-Bopp. The present results extend them to comets of only moderate brightness.

Comet ISON (formally known as C/2012 S1) was observed with ALMA on November 15-17, 2013, when it was only 75 million kilometers from the Sun (about half the distance of the Earth to the Sun). Comet Lemmon (formally known as C/2012 F6) was observed on June 1-2, 2013, when it was 224 million kilometers from the Sun (about 1.5 times the distance of the Earth to the Sun).

Fig. 5: Visualization with ALMA of the 3D distribution of the organic molecule HCN in the atmosphere of comet Lemmon. Credit: Visualization by Brian Kent (NRAO/AUI/NSF)

“The high sensitivity achieved in these studies paves the way for observations of perhaps hundreds of the dimmer or more distant comets,” said Goddard’s Stefanie Milam, a study co-author. “The findings suggest that it should also be possible to map more complex molecules that have so far eluded detection in comets.”

This research was funded by the NASA Astrobiology Institute through the Goddard Center for Astrobiology and by NASA’s Planetary Atmospheres and Planetary Astronomy programs.

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), 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.

From ALMA: “Cometary Belt around Distant Multi-Planet System Hints at Hidden or Wandering Planets”

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

From ALMA

17 May, 2016 [Retrieved from the ALMA web site]

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

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu

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

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

ALMA image of dusty cometary ring around HR 8799, the only star where multiple planets have been imaged. The new data suggest the planets either migrated or another undiscovered planet is present. The zoom-in portion of the image, taken with ESO’s Very Large Telescope, shows the location of the known planets in this system in relation to a graphical representation of the central star. Credit: Booth et al., ALMA (NRAO/ESO/NAOJ); A. Zurlo, et al

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

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have made the first high-resolution image of the cometary belt (a region analogous to our own Kuiper belt) around HR 8799, the only star where multiple planets have been imaged directly. The shape of this dusty disk, particularly its inner edge, is surprisingly inconsistent with the orbits of the planets, suggesting that either they changed position over time or there is at least one more planet in the system yet to be discovered.

“This data really allow us to see the inner edge of this disk for the first time,” explains Mark Booth from Pontificia Universidad Católica de Chile and lead author of the study. “By studying the interactions between the planets and the disk, this new observation shows that either the planets that we see have had different orbits in the past or there is at least one more planet in the system that is too small to have been detected.”

The disk, which fills a region 150 to 420 times the Sun-Earth distance, is produced by the ongoing collisions of cometary bodies in the outer reaches of this star system. ALMA was able to image the emission from millimeter-size debris in the disk; according to the researchers, the small size of these dust grains suggests that the planets in the system are larger than Jupiter. Previous observations with other telescopes at shorter wavelengths did not detect this discrepancy in the disk. It is not clear if this difference is due to the low resolution of the previous observations or because different wavelengths are sensitive to different grain sizes, which would be distributed slightly differently.

HR 8799 is a young star approximately 1.5 times the mass of the Sun located 129 light-years from Earth in the direction of the constellation Pegasus.

“This is the very first time that a multi-planet system with orbiting dust is imaged, allowing for direct comparison with the formation and dynamics of our own Solar System,” explains Antonio Hales, co-author of the study from the National Radio Astronomy Observatory in Charlottesville, Virginia.

Additional information

These results were published in the Monthly Notices of the Royal Astronomical Society titled “Resolving the Planetesimal Belt of HR 8799 with ALMA” by Booth et al., May 2016.
Preprint: http://arxiv.org/abs/1603.04853

The research team was composed by Mark Booth ([1], [2]), Andrés Jordán ([1], [3]), Simón Casassus ([2], [4]), Antonio S. Hales ([5], [6]), William R. F. Dent ([5]), Virginie Faramaz ([1]), Luca Matrà ([7],[8]), Denis Barkats ([9]), Rafael Brahm ([1], [3]) Jorge Cuadra ([1], [2]).

[1] Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago, Chile
[2] Millennium Nucleus “Protoplanetary Disks”
[3] Millennium Institute of Astrophysics, Vicuña Mackenna 4860, Santiago, Chile
[4] Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago, Chile
[5] Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago, Chile
[6] National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, Virginia, 22903-2475, USA
[7] Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
[8] European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago, Chile
[9] Harvard University, 60 Garden Street, Cambridge, MA 02138, USA

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), 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.

From ALMA: “ALMA Gives Christmas Comet Its Close-up”

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

From ALMA

20 December, 2018

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

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu

ALMA image of comet 46P/Wirtanen taken on December 2 as the comet approached Earth. The ALMA image shows the concentration and distribution of hydrogen cyanide (HCN) molecules near the center of the comet’s coma. Credit: ALMA (ESO/NAOJ/NRAO); M. Cordiner, NASA/CUA

As comet 46P/Wirtanen neared Earth on December 2, astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) took a remarkably close look at its innermost regions. ALMA imaged the comet when it was approximately 16.5 million kilometers from Earth. At its closet on December 16, the comet – one of the brightest in years — was approximately 11.4 million kilometers from Earth, or 30 times the distance from the Earth to the moon.

“This comet is causing a stir in the professional and amateur astronomy communities due to its combined brightness and proximity, which allows us to study it in unprecedented detail” said NASA’s Martin Cordiner, who led the team that made the ALMA observations. “As the comet drew nearer to the Sun, its icy body heated up, releasing water vapor and various other particles stored inside, forming the characteristic puffed-up coma and elongated tail.”

The ALMA image of comet 46P/Wirtanen zooms-in to very near its nucleus – the solid “dirty snowball” of the comet itself — to image the natural millimeter-wavelength “glow” emitted by molecules of hydrogen cyanide (HCN), a simple organic molecule that forms an ethereal atmosphere around the comet. ALMA, using its remarkable ability to see fine details, was able to detect and image the fine-scale distribution of this particular molecule.

The HCN image shows a compact region of gas and an extended, diffuse, and somewhat asymmetrical, pattern in the inner portion of the coma. Due to the extreme proximity of this comet, most of the extended coma is resolved out, so these observations are only sensitive to the innermost regions, in the immediate vicinity of the nucleus.

The astronomers also performed observations of more complex molecules on Dec 9, when the comet was 13.6 million kilometers from Earth.

Comet 46P/Wirtanen orbits the Sun once every five-and-a-half years, which is remarkably brisk compared to its more famous cousin Halley’s Comet, which has an orbital period of about 75 years. Other bright comets can have periods that are on the order of hundreds and even thousands of years. The comet may yet be visible to the naked eye.

For comparison, an optical view of the comet taken by an amateur astrophotographer is shown.

An optical image of comet 46P/Wirtanen taken from Chiefland, Florida, on December 4, 2018. Camera details: Canon 6D camera, MN190mm astrograph telescope. Credit: Derek Demeter, Emil Buehler Planetarium

Though they appear to be similar, the ALMA image spans an area of the sky only about 5 arcseconds – about 1000 times smaller than the optical image – meaning ALMA is looking at the very fine-scale features in the coma.

Side-by-side comparison shows an ALMA image of comet 46P/Wirtanen (left) and an optical image (right). The ALMA image has approximately 1000 times the resolution of the optical image and zooms in on the inner portion of the comet’s diffuse coma. Credit: ALMA (ESO/NAOJ/NRAO), M. Cordiner, NASA/CUA; Derek Demeter, Emil Buehler Planetarium

This and previous observations of comets with ALMA confirm that they are rich in organic molecules and may therefore have seeded the early Earth with the chemical building blocks of life.

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), 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.

From ALMA: “Mystery of coronae around supermassive black holes deepens”

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

From ALMA

17 December, 2018

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

Calum Turner
ESO Assistant Public Information Officer
Garching bei München, Germany
Phone: +49 89 3200 6670
Email: calum.turner@eso.org

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu

Artist’s rendering of the corona around a black hole. Credit: RIKEN, All rights reserved.

Researchers from RIKEN have used observations from the Atacama Large Millimeter/submillimeter Array (ALMA) to measure the strength of magnetic fields near two supermassive black holes at the center of an important group of active galaxies. Surprisingly, the strengths of the magnetic fields do not appear sufficient to power the coronae, clouds of superheated plasma, that are observed around the black holes at the centers of those galaxies.

It has long been known that the supermassive black holes that lie at the centers of galaxies, sometimes outshining their host galaxies, have coronae of superheated plasma around them, like the Sun. For black holes, these coronae can be heated to a phenomenal temperature of one billion degrees Celsius. It was long assumed that, like that of the Sun, the coronae were heated by magnetic field energies. However, these magnetic fields had never been measured, leaving uncertainty regarding the exact mechanism.

In a 2014 paper, the research group predicted that electrons in the plasma surrounding the black holes would emit a special kind of light, known as synchrotron radiation, as they exist together with the magnetic forces in the coronae. Specifically, this radiation would be in the radio band, meaning light with a very long wavelength and low frequency. And the group set out to measure the fields.

They decided to look at data from two “nearby”—in astronomical terms—active galactic nuclei—IC 4329A, which is about 200 million light years away, and NGC 985, which is approximately 580 million light years away. They began by taking measurements from the ALMA observatory in Chile, and then compared them to observations from two other radio telescopes: the VLA observatory in the United States, and the ATCA observatory in Australia, which measure slightly different bands; and found indeed that there was an excess of radio emission originating from synchrotron radiation, in addition to emissions from the jets case out by the black holes.

NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

CSIRO Australia Compact Array, six radio telescopes at the Paul Wild Observatory, is an array of six 22-m antennas located about twenty five kilometres (16 mi) west of the town of Narrabri in Australia.

Through the observations, the team deduced that the coronae had a size of about 40 Schwartzchild radii (the radius of a black hole from which not even light can escape), and a strength of about 10 gauss, a figure that is a bit more than the magnetic field at the surface of the earth but quite a bit less than that given out by a typical refrigerator magnet.

“The surprise,” says Yoshiyuki Inoue, the first author of the paper, “is that although we confirmed the emission of radio synchrotron radiation from the coronae in both objects, it turns out that the field of the magnetic field we measured is much too weak to be able to drive the intense heating of the coronae around these black holes.” He also notes that the same phenomenon was observed in both galaxies, implying that it could be a general phenomenon.

Looking to the future, Inoue says that the group plans to look for signs of powerful gamma rays that should accompany the radio emissions, to further understand what is happening in the environment near supermassive black holes.

Additional Information

This research is accepted for publication under the title “Detection of Coronal Magnetic Activity in Nearby Active Supermassive Black Holes” by Y. Inoue et al. in The Astrophysical Journal.

See the full article here .

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

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

From Imperial College London: “Young star caught forming around another star”

From Imperial College London

14 December 2018
Hayley Dunning

A small star has been observed forming out of the dust surrounding a larger star, in a similar way to how planets are born.

Astronomers were observing the formation of a massive young star, called MM 1a, when they discovered an unexpected object nearby.

MM 1a is surrounded by rotating disc of gas and dust. But orbiting just beyond this disc, they discovered a faint object they called MM 1b, which they discovered was a smaller star. MM 1b is believed to have formed out of the gas and dust surrounding the larger MM 1a.

The team of astronomers, led by the University of Leeds and including an Imperial College London researcher, have published their discovery today in the journal Astrophysical Journal Letters.

Co-author Dr Thomas Haworth, from the Department of Physics at Imperial, helped predict what might be observed around MM 1a, and then to interpret what they actually found. He said: “It’s great when the new data surprises you, which was definitely the case here.

“Seeing the disc itself in so much detail is exciting, but detecting a second star forming within the disc, perhaps in a similar way to how planets form, was a huge unexpected bonus. There is a lot of work ahead of us to fully understand the consequences of this new discovery.”

An entirely different formation process

Stars form within large clouds of gas and dust in interstellar space. When these clouds collapse under gravity, they begin to rotate faster, forming a disc around them. It is in these discs that planets can form around low mass stars like our Sun.

Lead author Dr John Ilee, from the School of Physics and Astronomy at the University of Leeds, said: “In this case, the star and disc we have observed is so massive that, rather than witnessing a planet forming in the disc, we are seeing another star being born.”

By measuring the amount of radiation emitted by the dust and subtle shifts in the frequency of light emitted by the gas, the researchers were able to calculate the mass of MM 1a and MM 1b.

They found that MM 1a weighs 40 times the mass of our Sun. The smaller orbiting star MM 1b was calculated to weigh less than half the mass of our Sun.

Observation of the dust emission (green) and hot gas rotating in the disc around MM 1a (red is receding gas, blue is approaching gas). MM 1b is seen the lower left. Credit: J. D. Ilee / University of Leeds.

Dr Ilee said: “Many older massive stars are found with nearby companions. But these ‘binary’ stars are often very equal in mass, and so likely formed together as siblings. Finding a young binary system with a mass ratio of 80:1 is very unusual, and suggests an entirely different formation process for both objects.”

The team believe stars like MM 1b could form in the outer regions of cold, massive discs. These discs are unable to hold themselves up against the pull of their own gravity, collapsing into one or more fragments.

The team believe their discovery is one of the first examples of a ‘fragmented’ disc to be detected around a massive young star.

Only a million years to live

Dr Duncan Forgan, a co-author from the Centre for Exoplanet Science at the University of St Andrews, added: “I’ve spent most of my career simulating this process to form giant planets around stars like our Sun. To actually see it forming something as large as a star is really exciting.”

The researchers note that newly discovered young star MM 1b could also be surrounded by its own disc, which may have the potential to form planets of its own – but it will need to be quick.

Dr Ilee added: “Stars as massive as MM 1a only live for around a million years before exploding as powerful supernovae, so while MM 1b may have the potential to form its own planetary system in the future, it won’t be around for long.”

The astronomers made this surprising discovery by using a unique new instrument situated high in the Chilean desert – the Atacama Large Millimetre/submillimetre Array (ALMA).

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

Using the 66 individual dishes of ALMA together in a process called interferometry, the astronomers were able to simulate the power of a single telescope nearly 4km across, allowing them to image the material surrounding the young stars for the first time.

Funders for this research include the Science and Technologies Facilities Council (UK) and the European Research Council.

See the full article here .

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Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

From ALMA: “ALMA Campaign Provides Unprecedented Views of the Birth of Planets”

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

From ALMA

12 December, 2018

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

Laura Pérez
Department of Astronomy, University of Chile
Santiago, Chile
Cell phone: +5699494640
Email: lperez@das.uchile.cl

Charles E. Blue
Public Information Officer
National Radio Astronomy Observatory Charlottesville, Virginia – USA
Phone: +1 434 296 0314
Cell phone: +1 202 236 6324
Email: cblue@nrao.edu

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

Calum Turner
ESO Assistant Public Information Officer
Garching bei München, Germany
Phone: +49 89 3200 6670
Email: calum.turner@eso.org

ALMA’s high-resolution images of nearby protoplanetary disks, which are results of the Disk Substructures at High Angular Resolution Project (DSHARP). Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; N. Lira

Animated GIF showing the ALMA images of 20 protoplanetary disks observed by DSHARP project. Credit: ALMA (ESO/NAOJ/NRAO), Andrews et al.; N. Lira.

Planets Forming around a Young Star from NRAO Outreach on Vimeo.

ALMA Timelapse for Afterite Ballet from ALMA Observatory on Vimeo.

Reel drone flight over ALMA antennas from ALMA Observatory on Vimeo.

Astronomers have already cataloged nearly 4,000 exoplanets in orbit around distant stars. Though we have learned much about these newfound worlds, there is still much we do not know about the steps of planet formation and the precise cosmic recipes that spawn the wide array of planetary bodies we have already uncovered, including so-called hot Jupiters, massive rocky worlds, icy dwarf planets, and – hopefully someday soon – distant analogs of Earth.

To help answer these and other intriguing questions about the birth of planets, a team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA)has conducted one of the deepest surveys ever of protoplanetary disks, the planet-forming dust belts around young stars.

“This specific Large Programis important because it takes one of the fundamental science goals of ALMA, which is to understand the process of planet formation and takes it from previous studies, which were either very small samples or single objects, to a completely new context, allowing statistical views” explains Stuartt Corder, Deputy Director of ALMA; “Are these kinds of structures common or rare? This more statistical approach allows researchers to answer questions that are much more fundamental to the process of planet formation.”

Known as the Disk Substructures at High Angular Resolution Project (DSHARP), this Large Programof ALMA has yielded stunning, high-resolution images of 20 nearby protoplanetary disks and given astronomers new insights into the variety of features they contain and the speed with which planets can emerge.

The results of this survey are contained in a series of ten papers that are accepted for publication in The Astrophysical Journal Letters. Link to .pdf https://arxiv.org/pdf/1812.04045.pdf

According to the researchers, the most compelling interpretation of these observations is that large planets, likely similar in size and composition to Neptune or Saturn, form quickly, much faster than current theory would indicate. The also tend to form in the outer reaches of their solar systems at tremendous distances from their host stars.

Such precocious formation could also help explain how rocky, Earth-size worlds are able to evolve and grow, surviving their presumed self-destructive adolescence.

“The goal of this months-long observing campaign was to search for structural commonalities and differences in protoplanetary disks. ALMA’s remarkably sharp vision has revealed previously unseen structures and unexpectedly complex patterns,” said Sean Andrews, an astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA) and a leader of the ALMA observing campaign along with Andrea Isella of Rice University and Cornelis Dullemond of Heidelberg University. “We are seeing distinct details around a wide assortment of young stars of various masses. The most compelling interpretation of these highly diverse, small-scale features is that there are unseen planets interacting with the disk material.”

The leading models for planet formation hold that planets are born by the gradual accumulation of dust and gas inside a protoplanetary disk, beginning with grains of dust that coalesce to form larger and larger rocks, until asteroids, planetesimals, and planets emerge. This hierarchical process should take many millions of years to unfold, suggesting that its impact on protoplanetary disks would be most prevalent in older, more mature systems. Mounting evidence, however, indicates that is not always the case.

ALMA’s early observations of young protoplanetary disks, some only about one million years old, reveal striking and surprising structures, including prominent rings and gaps, which appear to be the hallmarks of planets. Astronomers were initially cautious to ascribe these features to the actions of planets since other natural process could be at play.

“It was surprising to see possible signatures of planet formation in the very first high-resolution images of young disks. It was important to find out whether these were anomalies or if those signatures were common in disks,” said Jane Huang, a graduate student at CfA and a member of the research team.

Since the sample set was so small, however, it was impossible to draw any overarching conclusions. It could have been that astronomers were observing atypical systems. More observations on a variety of protoplanetary disks were needed to determine the most likely cause of the features we were seeing.

The DSHARP campaign was designed to do precisely that by studying the relatively small-scale distribution of dust particles around 20 nearby protoplanetary disks. These dust particles naturally glow in millimeter-wavelength light, enabling ALMA to precisely map the density distribution of small, solid particles around young stars.

Depending on the star’s distance from Earth, ALMA was able to distinguish features as small as a few Astronomical Units(An Astronomical Unit is the average distance of the Earth to the Sun – about 150 million kilometers, which is a useful scale for measuring distances on the scale of star systems). Using these observations, the researchers were able to image an entire population of nearby protoplanetary disks and study their AU-scale features.

The researchers found that many substructures – concentric gaps, narrow rings – are common to nearly all the disks, while large-scale spiral patterns and arc-like features are also present in some of the cases. Also, the disks and gaps are present at a wide range of distances from their host stars, from a few AU to more than 100 AU, which is more than three times the distance of Neptune from our Sun.

These features, which could be the imprint of large planets, may explain how rocky Earth-like planets are able to form and grow. For decades, astronomers have puzzled over a major hurdle in planet-formation theory: Once planetesimals grow to a certain size – about one kilometer is diameter – the dynamics of a smooth protoplanetary disk would induce them to fall in on their host star, never acquiring the mass necessary to form planets like Mars, Venus, and Earth.

The dense rings of dust we now see with ALMA would produce a safe haven for rocky worlds to fully mature. Their higher densities and the concentration of dust particles would create perturbations in the disk, forming zones where planetesimals would have more time to grow into fully fledged planets.

“When ALMA truly revealed its capabilities with its iconic image of HL Tau, we had to wonder if that was an outlier since the disk was comparatively massive and young,” noted Laura Perez with the University of Chile and a member of the research team. “These latest observations show that, though striking, HL Tau is far from unusual and may actually represent the normal evolution of planets around young stars.”

Additional Information

This research is presented in the following papers accepted to the Astrophysical Journal Letters.

“The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview: S. Andrews, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): II. Characteristics of Annular Substructures,” J. Huang, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): III. Spiral Structures in the Millimeter Continuum of the Elias 27, IM Lup, and WaOph 6 Disks,” J. Huang, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): IV. Characterizing Substructures and Interactions in Disks around Multiple Star Systems,” N. Kurtovic, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): V. Interpreting ALMA Maps of Protoplanetary Disks in Terms of a Dust Model” T. Birnstiel, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): VI. Dust Trapping in Thin-Ringed Protoplanetary Disks,” C. Dullemond, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): VII. The Planet-Disk Interactions Interpretation” S. Zhang, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): VIII. The Rich Ringed Substructures in the AS 209 Disk,” V, Guzmán, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): IX. A High Definition Study of the HD 163296 Planet Forming Disk” A. Isella, et al.
“The Disk Substructures at High Angular Resolution Project (DSHARP): X. Multiple Rings, a Misaligned Inner Disk, and a Bright Arc in the Disk around the T Tauri Star HD 143006,” L. Pérez, et al.

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), 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.

From ALMA via Science News: “Astronomers find far-flung wind from a black hole in the universe’s first light”

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

From ALMA

via

Science News

December 5, 2018
Lisa Grossman

The discovery could shed light on how galaxies and black holes grow up together.

A MIGHTY WIND Supermassive black holes in the centers of galaxies can blow gas and plasma far away from their galaxies, as shown in this artist’s illustration based on the Pinwheel galaxy. NASA JPL-Caltech

Astronomer Mark Lacy and colleagues used the Atacama Large Millimeter Array in Chile to observe the universe’s first light, and found evidence of gusts flowing from a type of black hole called a quasar. The wind extends about 228,000 light-years away from the galaxy that surrounds the quasar. Previously, astronomers had seen signs of these winds only about 3,000 light-years from their galaxies.

The result, published [MNRAS] November 12 could help resolve questions about how black holes can grow with their galaxies, or shut galaxies down for good.

Black holes are best known for gravitationally gobbling everything that veers too close. Paradoxical as it sounds, supermassive black holes can also send material in the opposite direction, driving powerful flows of charged gas and plasma away from their host galaxies.

These black holes are victims of their own success, pulling in more material than they can consume at once. The excess material surrounds black holes in a tight swirling disk, where friction heats it to hundreds of millions of degrees Celsius. The black hole plus that bright disk is a quasar.

All that heat, plus some help from magnetic fields [Nature] , create great gusts that carry gas and plasma away (SN Online: 3/6/17). “The black hole can’t swallow all of that stuff,” says Lacy, of the National Radio Astronomy Observatory in Charlottesville, Va. “It has to blow some of it out.”

Measuring such winds’ extent and energies could help scientists figure out how material spit out by the black holes might influence the way the galaxies grow and evolve. If the wind doesn’t blow far enough from the galaxy, for example, the material in the gusts could fall back down into the galaxy and be recycled into new stars — or blown back out again [Nature] (SN: 7/21/18, p. 16).

But if a black hole’s wind is too powerful, it could steal all of a galaxy’s star-forming gas and shut the galaxy down. That could explain why there appears to be a mass limit for galaxies: Most have fewer than 10 trillion times the sun’s mass worth of stars. Theoretical calculations suggest that if a black hole can blow away 1 or 2 percent of the total energy of a quasar in the wind, that would be enough to shut a galaxy down. And that might just happen to be when a galaxy weighs about 10 trillion suns.

To figure out if that actually happens, however, astronomers need to know how far away real black holes’ winds can reach and how much energy they carry.

Lacy and his colleagues observed a quasar called HE 0515-4414, about 268 million light-years away from Earth, to see how the hot gas of its wind scattered photons from the cosmic microwave background, the oldest light in the universe (SN Online: 7/24/18). “It’s almost like the wind casts a shadow,” Lacy says. “You see this hole in the microwave background.”

This phenomenon is called the Sunyaev-Zeldovich effect. Other astronomers predicted in 1999 that the effect could be used to measure the energies and extents of these winds. But ALMA is the first telescope sensitive enough to detect the effect.

In addition to tracking how far HE 0515-4414’s wind blows, the team also measured the gust’s energy. It was much less than expected, about 0.01 percent of the quasar’s total energy. That’s nowhere near enough to explain the galaxy mass limit.

“That doesn’t mean the theory is completely dead,” Lacy says. The ALMA observations suggested that, rather than blowing continuously, the wind blew a large, long-lived bubble of material that can last for many millions of years, longer than most quasars are active. That bubble could keep star-forming material out of the galaxy indefinitely, shutting the galaxy down even without an actively blowing black hole.

“To me that’s the next frontier, to find these ghost outflows hanging around quasars that might be dead,” says astrophysicist Priyamvada Natarajan of Yale University, who wrote the 1999 paper predicting this observation method as a graduate student at the Institute of Astronomy at the University of Cambridge.

“I’m very excited,” she says. “This is the first detection where we can actually measure how much kinetic energy is being transmitted to the environment of the galaxy.” But she cautions that the new study focuses on only one object. Astronomers will need to find more quasar winds before drawing conclusions on how black holes affect their galaxies in general.

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), 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.