From ALMA: “ALMA Shows What’s Inside Jupiter’s Storms”

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

From ALMA

22 August, 2019

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

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

Radio image of Jupiter made with ALMA. Bright bands indicate high temperatures and dark bands low temperatures. The dark bands correspond to the zones on Jupiter, which are often white at visible wavelengths. The bright bands correspond to the brown belts on the planet. This image contains over 10 hours of data, so fine details are smeared by the planet’s rotation. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al.; NRAO/AUI NSF, S. Dagnello

Swirling clouds, big colorful belts, giant storms. The beautiful and incredibly turbulent atmosphere of Jupiter has been showcased many times. But what is going on below the clouds? What is causing the many storms and eruptions that we see on the ‘surface’ of the planet? However, to study this, visible light is not enough. We need to study Jupiter using radio waves.

New radio wave images made with the Atacama Large Millimeter/submillimeter Array (ALMA) provide a unique view of Jupiter’s atmosphere down to fifty kilometers below the planet’s visible (ammonia) cloud deck.

“ALMA enabled us to make a three-dimensional map of the distribution of ammonia gas below the clouds. And for the first time, we were able to study the atmosphere below the ammonia cloud layers after an energetic eruption on Jupiter,” said Imke de Pater of the University of California, Berkeley (EE. UU.).

The atmosphere of giant Jupiter is made out of mostly hydrogen and helium, together with trace gases of methane, ammonia, hydrosulfide, and water. The top-most cloud layer is made up of ammonia ice. Below that is a layer of solid ammonia hydrosulfide particles, and deeper still, around 80 kilometers below the upper cloud deck, there likely is a layer of liquid water. The upper clouds form the distinctive brown belts and white zones seen from Earth.

Many of the storms on Jupiter take place inside those belts. They can be compared to thunderstorms on Earth and are often associated with lightning events. Storms reveal themselves in visible light as small bright clouds, referred to as plumes. These plume eruptions can cause a major disruption of the belt, which can be visible for months or years.

The ALMA images were taken a few days after amateur astronomers observed an eruption in Jupiter’s South Equatorial Belt in January 2017. A small bright white plume was visible first, and then a large-scale disruption in the belt was observed that lasted for weeks after the eruption.

De Pater and her colleagues used ALMA to study the atmosphere below the plume and the disrupted belt at radio wavelengths and compared these to UV-visible light and infrared images made with other telescopes at approximately the same time.

“Our ALMA observations are the first to show that high concentrations of ammonia gas are brought up during an energetic eruption,” said de Pater. “The combination of observations simultaneously at many different wavelengths enabled us to examine the eruption in detail. Wich led us to confirm the current theory that energetic plumes are triggered by moist convection at the base of water clouds, which are located deep in the atmosphere. The plumes bring up ammonia gas from deep in the atmosphere to high altitudes, well above the main ammonia cloud deck,” she added.

“These ALMA maps at millimeter wavelengths complement the maps made with the National Science Foundation’s Very Large Array in centimeter wavelengths,” said Bryan Butler of the National Radio Astronomy Observatory.

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)

“Both maps probe below the cloud layers seen at optical wavelengths and show ammonia-rich gases rising into and forming the upper cloud layers (zones), and ammonia-poor air sinking down (belts).”

“The present results show superbly what can be achieved in planetary science when an object is studied with various observatories and at various wavelengths”. Explains Eric Villard, an ALMA astronomer part of the research team. “ALMA, with its unprecedented sensitivity and spectral resolution at radio wavelengths, worked together successfully with other major observatories around the world, to provide the data to allow a better understanding of the atmosphere of Jupiter.”

Flat map of Jupiter in radio waves with ALMA (top) and visible light with the Hubble Space Telescope (bottom). The eruption in the South Equatorial Belt is visible in both images. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al.; NRAO/AUI NSF, S. Dagnello; NASA/Hubble

Science paper:
First ALMA Millimeter Wavelength Maps of Jupiter, with a Multi-Wavelength Study of Convection
https://arxiv.org/pdf/1907.11820.pdf

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 Identified Dark Ancestors of Massive Elliptical Galaxies”

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

From ALMA

7 August, 2019

Tao Wang
Postdoctoral fellow
Institute of Astronomy, The University of Tokyo / National Astronomical Observatory of Japan
Email: taowang@ioa.s.u-tokyo.ac.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

Mariya Lyubenova
ESO Outreach Astronomer
Garching bei München, Germany
Phone: +49 89 32 00 61 88
Email: mlyubeno@eso.org

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

An artistic representation of the distant galaxies observed with ALMA. ALMA identified faint galaxies invisible to the Hubble Space Telescope. For the research team, these galaxies precede the massive elliptical galaxies of the present Universe. Credits: NAOJ

Astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to identify 39 faint galaxies that are not seen with the Hubble Space Telescope’s most in-depth view of the Universe, 10 billion light-years away. They are ten times more numerous than similarly massive but optically–bright galaxies detected with Hubble. The research team assumes that these faint galaxies precede massive elliptical galaxies in the present Universe. However, no significant theories for the evolution of the Universe have predicted such an abundant population of star-forming, dark, massive galaxies. The new ALMA results throw into question our understanding of the early Universe. These results appear in the latest issue of the journal Nature.

“Previous studies have found extremely active star-forming galaxies in the early Universe, but their population is quite limited,” says Tao Wang, lead author of this research at the University of Tokyo, the French Alternative Energies and Atomic Energy Commission (CEA), and the National Astronomical Observatory of Japan (NAOJ). “Star formation in the dark galaxies we identified is less intense, but they are 100 times more abundant than the extreme starbursts. It is important to study such a major component of the history of the Universe to comprehend galaxy formation.”

Wang and his team targeted three ALMA windows to the deep Universe opened up by the Hubble Space Telescope (HST): the CANDELS fields. The team discovered 63 extremely red objects in the infrared images taken by NASA’s Spitzer Space Telescope: they are too red to be detected with HST. However, Spitzer’s limited spatial resolution prevented astronomers from identifying their nature.

ALMA detected submillimeter-wave emission from 39 out of the 63 extremely red objects. Thanks to its high resolution and sensitivity, ALMA confirmed that they are massive, star-forming galaxies that are producing stars 100 times more efficiently than the Milky Way. These galaxies are representative of the majority of massive galaxies in the Universe 10 billion years ago, most of which have so far been missed by previous studies.

“By maintaining this rate of star formation, these ALMA-detected galaxies will likely transform into the first population of massive elliptical galaxies formed in the early Universe,” says David Elbaz, an astronomer at CEA, and coauthor on the paper, “But there is a problem. They are unexpectedly abundant.” The researchers estimated their number density to be equivalent to 530 objects in a square degree in the sky. This number density well exceeds predictions from current theoretical models and computer simulations. Also, according to the widely accepted model of the Universe with a particular type of dark matter, it is challenging to build a large number of massive objects in such an early phase of the Universe. Together, the present ALMA results challenge our current understanding of the evolution of the Universe.

“Like the galaxy Messier 87, from which astronomers recently obtained the first-ever image of a black hole, massive elliptical galaxies are located in the heart of galaxy clusters.

The first image of a black hole, Messier 87 Credit Event Horizon Telescope Collaboration, via NSF and ERC 4.10.19

Katie Bouman of Harvard Smithsonian Observatory for Astrophysics, headed to Caltech, with EHT hard drives from Messier 87

Scientist believes that these galaxies formed most of their stars in the early Universe,” explains Kotaro Kohno, a professor at the University of Tokyo and member of the research team. “However, previous searches for the progenitors of these massive galaxies have been unsuccessful because they were based solely on galaxies that are easily detectable by HST. The discovery of this large number of massive, HST-dark galaxies provides direct evidence for the early assembly of massive galaxies during the first billion years of the Universe.” More detailed follow-up observations with ALMA and NASA’s James Webb Space Telescope are essential to provide further insights into the nature of these galaxies. New studies could enable a complete view of galaxy formation in the early Universe.”

ALMA identified 39 faint galaxies that are not seen with the Hubble Space Telescope’s most in-depth view of the Universe 10 billion light-years away. This example image shows a comparison of Hubble and ALMA observations. The squares numbered from 1 to 4 are the locations of faint galaxies unseen in the Hubble image. Credit: The University of Tokyo/CEA/NAOJ.

The research team members are:
T. Wang (The University of Tokyo/CEA/National Astronomical Observatory of Japan), C. Schreiber (CEA/Leiden University/Oxford University), D. Elbaz (CEA), Y. Yoshimura (The University of Tokyo), K. Kohno (The University of Tokyo), X. Shu (Anhui Normal University), Y. Yamaguchi (The University of Tokyo), M. Pannella (Ludwig-Maximilians-Universitat,), M. Franco (CEA), J. Huang (National Astronomical Observatories of China), C.-F. Lim (Academia Sinica Institute of Astronomy and Astrophysics), and W.-H. Wang (Academia Sinica Institute of Astronomy and Astrophysics).

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 NRAO: “ALMA Dives into Black Hole’s ‘Sphere of Influence’”

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

From ALMA

via

National Radio Astronomy Observatory

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

Credit: ALMA (ESO/NAOJ/NRAO), B. Boizelle; NRAO/AUI/NSF, S. Dagnello; Hubble Space Telescope (NASA/ESA); Carnegie-Irvine Galaxy Survey

ALMA has made the most precise measurements of cold gas swirling around a supermassive black hole — the cosmic behemoth at the center of the giant elliptical galaxy NGC 3258. The multi-color ellipse reflects the motion of the gas orbiting the black hole, with blue indicating motion toward us and red motion away from us. The inset box represents how the orbital velocity changes with distance from the black hole. The material was found to rotate faster the closer in the astronomers observed to the black hole, enabling them to accurately calculate its mass: a whopping 2.25 billion times the mass of our Sun.

What happens inside a black hole stays inside a black hole, but what happens inside a black hole’s “sphere of influence” – the innermost region of a galaxy where a black hole’s gravity is the dominant force – is of intense interest to astronomers and can help determine the mass of a black hole as well as its impact on its galactic neighborhood.

New observations with the Atacama Large Millimeter/submillimeter Array (ALMA) provide an unprecedented close-up view of a swirling disk of cold interstellar gas rotating around a supermassive black hole. This disk lies at the center of NGC 3258, a massive elliptical galaxy about 100 million light-years from Earth. Based on these observations, a team led by astronomers from Texas A&M University and the University of California, Irvine, have determined that this black hole weighs a staggering 2.25 billion solar masses, the most massive black hole measured with ALMA to date.

Though supermassive black holes can have masses that are millions to billions of times that of the Sun, they account for just a small fraction of the mass of an entire galaxy. Isolating the influence of a black hole’s gravity from the stars, interstellar gas, and dark matter in the galactic center is challenging and requires highly sensitive observations on phenomenally small scales.

“Observing the orbital motion of material as close as possible to a black hole is vitally important when accurately determining the black hole’s mass.” said Benjamin Boizelle, a postdoctoral researcher at Texas A&M University and lead author on the study appearing in The Astrophysical Journal. “These new observations of NGC 3258 demonstrate ALMA’s amazing power to map the rotation of gaseous disks around supermassive black holes in stunning detail.”

Astronomers use a variety of methods to measure black hole masses. In giant elliptical galaxies, most measurements come from observations of the orbital motion of stars around the black hole, taken in visible or infrared light. Another technique, using naturally occurring water masers (radio-wavelength lasers) in gas clouds orbiting around black holes, provides higher precision, but these masers are very rare and are associated almost exclusively with spiral galaxies having smaller black holes.

During the past few years, ALMA has pioneered a new method to study black holes in giant elliptical galaxies. About 10 percent of elliptical galaxies contain regularly rotating disks of cold, dense gas at their centers. These disks contain carbon monoxide (CO) gas, which can be observed with millimeter-wavelength radio telescopes.

By using the Doppler shift of the emission from CO molecules, astronomers can measure the velocities of orbiting gas clouds, and ALMA makes it possible to resolve the very centers of galaxies where the orbital speeds are highest.

“Our team has been surveying nearby elliptical galaxies with ALMA for several years to find and study disks of molecular gas rotating around giant black holes,” said Aaron Barth of UC Irvine, a co-author on the study. “NGC 3258 is the best target we’ve found, because we’re able to trace the disk’s rotation closer to the black hole than in any other galaxy.”

Just as the Earth orbits around the Sun faster than Pluto does because it experiences a stronger gravitational force, the inner regions of the NGC 3258 disk orbit faster than the outer parts due to the black hole’s gravity. The ALMA data show that the disk’s rotation speed rises from 1 million kilometers per hour at its outer edge, about 500 light-years from the black hole, to well over 3 million kilometers per hour near the disk’s center at a distance of just 65 light-years from the black hole.

The researchers determined the black hole’s mass by modeling the disk’s rotation, accounting for the additional mass of the stars in the galaxy’s central region and other details such as the slightly warped shape of the gaseous disk. The clear detection of rapid rotation enabled the researchers to determine the black hole’s mass with a precision better than one percent, although they estimate an additional systematic 12 percent uncertainty in the measurement because the distance to NGC 3258 is not known very precisely. Even accounting for the uncertain distance, this is one of the most highly precise mass measurements for any black hole outside of the Milky Way galaxy.

“The next challenge is to find more examples of near-perfect rotating disks like this one so that we can apply this method to measure black hole masses in a larger sample of galaxies,” concluded Boizelle. “Additional ALMA observations that reach this level of precision will help us better understand the growth of both galaxies and black holes across the age of the universe.”

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: “‘Moon Forming’ Circumplanetary Disk Discovered around Young Planet in Distant Star System”

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

From ALMA

11 July, 2019

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

Mariya Lyubenova
ESO Outreach Astronomer
Garching bei München, Germany
Phone: +49 89 32 00 61 88
Email: mlyubeno@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

ALMA image of the dust in PDS 70, a star system located approximately 370 light-years from Earth. Two faint smudges in the gap region of this disk are associated with newly formed planets. One such concentration of dust is a circumplanetary disk, the first such feature ever detected around a distant star. Credit: ALMA (ESO/NAOJ/NRAO); A. Isella.

Composite image of PDS 70. Comparing new ALMA data to earlier VLT observations, astronomers determined that the young planet designated PDS 70 c has a circumplanetary disk, a feature that is strongly theorized to be the birthplace of moons. Credit: ALMA (ESO/NOAJ/NRAO) A. Isella; ESO.

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,

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

ESO MUSE on the VLT on Yepun (UT4)

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have made the first-ever observations of a circumplanetary disk, the planet-girding belt of dust and gas that astronomers strongly theorize controls the formation of planets and gives rise to an entire system of moons, like the one found around Jupiter.

This young star system, PDS 70, is located approximately 370 light-years from Earth. Recently, astronomers confirmed the presence of two massive, Jupiter-like planets in orbit around the star. This discovery was made with the European Southern Observatory’s Very Large Telescope (VLT), which detected the warm glow naturally emitted by hydrogen gas accreting onto the planets.

The new ALMA observations instead image the faint radio waves given off by the tiny (about one tenth of a millimeter across) particles of dust around the star.

The ALMA data, combined with the earlier optical and infrared VLT observations, provide compelling evidence that a dusty disk capable of forming multiple moons surrounds the outermost known planet in the system.

“For the first time, we can conclusively see the telltale signs of a circumplanetary disk, which helps to support many of the current theories of planet formation,” said Andrea Isella, an astronomer at Rice University in Houston, Texas, and lead author on a paper published in The Astrophysical Journal Letters.

“By comparing our observations to the high-resolution infrared and optical images, we can see that an otherwise enigmatic concentration of tiny dust particles is a planet-girding disk of dust, the first such feature ever conclusively observed,” he said. According to the researchers, this is the first time that a planet has been seen in these three distinct bands of light (optical, infrared, and radio).

Unlike the icy rings of Saturn, which likely formed by the crashing together of comets and rocky bodies relatively recently in the history of our Solar System, a circumplanetary disk is the lingering remains of the planet-formation process.

The ALMA data also revealed two distinct differences between the two newly discovered planets. The closer in of the two, PDS 70 b, which is about the same distance from its star as Uranus is from the Sun, has a trailing mass of dust behind it resembling a tail. “What this is and what it means for this planetary system is not yet known,” said Isella. “The only conclusive thing we can say is that it is far enough from the planet to be an independent feature.”

The second planet, PDS 70 c, resides in the same location as a clear knot of dust seen in the ALMA data. Since this planet is shining so brightly in the infrared and hydrogen bands of light, the astronomers can convincingly say that a fully formed planet is already in orbit there and that nearby gas continues to be siphoned onto the planet’s surface, finishing its adolescent growth spurt.

This outer planet is located approximately 5.3 billion kilometers from the host star, about the same distance as Neptune from our Sun. Astronomers estimate that this planet is approximately 1 to 10 times the mass of Jupiter. “If the planet is on the larger end of that estimate, it’s quite possible there might be planet-size moons forming around it,” noted Isella.

The ALMA observations also add another important element to these observations.

Optical studies of planetary systems are notoriously challenging. Since the star is so much brighter than the planets, it is difficult to filter out the glare, much like trying to spot a firefly next to a searchlight. ALMA observations, however, don’t have that limitation since stars emit comparatively little light at millimeter and submillimeter wavelengths.

“This means we’ll be able to come back to this system at different periods and more easily map the orbit of the planets and the concentration of dust in the system,” concluded Isella. “This will give us unique insights into the orbital properties of solar systems in their very earliest stages of development.”

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: “Massive Stars Grow Same Way as Light Stars, Just Bigger”

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

From ALMA

8 July, 2019

Kazuhito Motogi
Assistant Professor
Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Japan.
Phone: +81-(0)83-933-5144

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

Mariya Lyubenova
ESO Outreach Astronomer
Garching bei München, Germany
Phone: +49 89 32 00 61 88
Email: mlyubeno@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

ALMA image of the massive protostar G353.273+0.641. Compact emission around the central protostar, disk, and gaseous envelope are shown in red, yellow, and blue. Asymmetry in the disk is clearly visible with the high-resolution ALMA observations. Credit: ALMA (ESO/NAOJ/NRAO), Motogi et al.

Artistic representation of the gas disk and the gas bag surrounding the massive protostar G353.273 + 0.641. Credits: NAOJ

Astronomers obtained the first detailed face-on view of a gaseous disk feeding the growth of a massive baby star. They found that it shares many usual features with lighter baby stars, implying that the formation process is the same, regardless of the final mass. This finding paves the way for a better understanding of star formation.

A protostar, a baby star still in the process of forming, is fed by a surrounding disk of gas falling towards the center. The details of the process, such as why stars form with a wide range of masses, are still unclear. Low mass stars forming in the vicinity of the Solar System, allow astronomers to see the process up-close. On the other hand, massive protostars are rare, and even the nearest are quite far away from us.

Kazuhito Motogi, an assistant professor at Yamaguchi University, Japan, and his team used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe a massive protostar called G353.273+0.641 (hereafter G353). Located 5500 light-years away in the constellation Scorpius, G353 has a mass ten times more massive than the Sun and is still growing. It is a unique target among massive protostars because we can see its gaseous disk from straight above. ALMA has revealed detailed views of several other enormous infant stars; however, most of them are in edge-on configurations, making it difficult to see the inner regions of the disks.

ALMA observations captured a rotating disk around G353 with a radius eight times larger than the orbit of Neptune. This sounds huge, but it is one of the smallest disks yet found around a massive protostar. ALMA also found an envelope of gas surrounding the system three times larger than the disk.

“We measured the gas infall rate from the outer envelope to the inner disk,” says Motogi. “This helps us to estimate the age of the baby star. Surprisingly it is only 3000 years old, the youngest among known massive protostars. We are witnessing the earliest phase of the growth of a giant star.”

Interestingly, the disk is not uniform; its south-eastern side is brighter than other parts, being the first time astronomers have seen an asymmetric disk around a massive protostar. The team also found instability in the disk which is going to fragment; which might be causing the asymmetry. These features are often seen around smaller protostars, suggesting that the essential physical processes are the same in low-mass and high-mass star formation.

“Previous studies had implied that the formation process might be different for stars of different masses,” says Motogi. “Our new observations show the similarity: an important step to understand how massive protostars gain mass from the surroundings.”

These observation results were published in The Astrophysical Journal Letters on May 29, 2019.

The research team members are:

Kazuhito Motogi (Yamaguchi University), Tomoya Hirota (National Astronomical Observatory of Japan/SOKENDAI), Masahiro N. Machida (Kyushu University), Yoshinori Yonekura (Ibaraki University), Mareki Honma (National Astronomical Observatory of Japan/SOKENDAI), Shigehisa Takakuwa (Kagoshima University), and Satoki Matsushita (Academia Sinica Institute of Astronomy and Astrophysics).

This research was supported by MEXT/JSPS KAKENHI (No. 15K17613, 19H05082, 16K05293, 17K05398, 18H05222, JP18K03703) and NAOJ ALMA Scientific Research Grant Number 2017-04A.

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: “Planetary Rings of Uranus Glow in Cold Light”

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

From ALMA

20 June, 2019

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 impression of the planet Uranus and its dark ring system. Rather than observing the reflected sunlight from these rings, astronomers have imaged the millimeter and mid-infrared “glow” naturally emitted by the frigidly cold particles of the rings themselves. Credit: NRAO/AUI/NSF; S. Dagnello

Using the Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Telescope (VLT), astronomers have imaged the cold, rock-strewn rings encircling the planet Uranus. Rather than observing the reflected sunlight from these rings, ALMA and the VLT imaged the millimeter and mid-infrared glow naturally emitted by the frigidly cold particles of the rings themselves. Only discovered in 1977, Uranus rings are invisible to most but the largest telescopes. However, they are surprisingly bright in the thermal images from ALMA and VLT.

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,

The thermal glow gives astronomers another window onto the rings, which only have been seen because they reflect a little light from the Sun. The new images taken by ALMA and the VLT allowed the team for the first time to measure the temperature of the rings: a cool 77º Kelvin, or 77º degrees above absolute zero; equivalent to -196.15º Celsius.

The observations also confirm that Epsilon, Uranus’s brightest and densest ring, differs from the other known rings within our solar system, in particular, the spectacularly beautiful rings of Saturn, that “are broad, bright and have a range of particle sizes, from micron-sized dust in the innermost D ring to tens of meters in size in the main rings,” said Imke de Pater, a UC Berkeley professor of astronomy. “The small end is missing in the main rings of Uranus; the brightest ring, epsilon, is composed of golf ball-sized and larger rocks.”

By comparison, Jupiter’s rings contain mostly small, micron-sized particles (a micron is a thousandth of a millimeter). Neptune’s rings are also mostly dust, and even Uranus has broadsheets of dust between its narrow main rings.

“We already know that the Epsilon ring is a bit weird because we don’t see the smaller stuff,” said Edward Molter, a graduate student from the same university. “Something has been sweeping the smaller stuff out, or it’s all glomming together. We just don’t know. This is a step to further understanding their composition and whether all of the rings came from the same source material or are different for each one.”

Rings could be former asteroids captured by the planet’s gravity, remnants of moons that crashed into one another and shattered, the remains of moons torn apart when they got too close to Uranus, or debris remaining from the formation 4.5 billion years ago.

The new data was published this week in The Astronomical Journal. De Pater and Molter led the ALMA observations, while Michael Roman and Leigh Fletcher from the University of Leicester, U.K., led the VLT observations.

“The rings of Uranus are compositionally different from Saturn’s main ring, in the sense that in optical and infrared, the albedo, thus the reflectance capacity, is much lower: they are really dark, like charcoal,” Molter said. “They are also extremely narrow compared to the rings of Saturn. The widest of them, Epsilon, varies from 20 to 100 kilometers wide, whereas Saturn’s are hundreds or tens of thousands of kilometers wide.”

The lack of dust-sized particles in Uranus’s main rings was first noted when Voyager 2 flew by the planet in 1986, however, the spacecraft was unable to measure the temperature of the rings. To date, astronomers have counted a total of 13 rings around the planet, with some bands of dust between the rings.

“It’s cool that we can even do this with the instruments we have,” Molter said. “I was just trying to image the planet as best I could, and I saw the rings. It was amazing.”

Both the VLT and ALMA observations were designed to explore the temperature structure of Uranus’ atmosphere, with VLT probing shorter wavelengths than ALMA.

“We were astonished to see the rings jump out clearly when we reduced the data for the first time,” Fletcher said.

This presents an exciting opportunity for the upcoming James Webb Space Telescope, which will be able to provide vastly improved details on the Uranian rings once launched in the coming decade.

The research team was composed by Edward M. Molter [1], Imke de Pater [1], Michael T. Roman [2], and Leigh N. Fletcher [2].

[1] Astronomy Department, University of California, Berkeley; Berkeley CA, 94720, USA.
[2] Department of Physics & Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, UK.

Composite image of Uranus’s atmosphere and rings at radio wavelengths, taken with the Atacama Large Millimeter/submillimeter Array (ALMA) in December 2017. The image shows thermal emission, or heat, from the rings of Uranus for the first time, enabling scientists to determine their temperature is a frigid 77 K (-320 F). Dark bands in Uranus’s atmosphere at these wavelengths show the presence of radiolight-absorbing molecules, in particular hydrogen sulfide (H2S) gas, whereas bright regions like the north polar spot contain very few of these molecules. Credit: ALMA (ESO/NAOJ/NRAO); E. Molter and I. de Pater.

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: “ALMA Finds Earliest Example of Merging Galaxies”

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

From ALMA

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

17 June, 2019

Composite image of B14-65666 showing the distributions of dust (red), oxygen (green), and carbon (blue), observed by ALMA and stars (white) observed by the Hubble Space Telescope. Credit: ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, Hashimoto et al.

Researchers using the Atacama Large Millimeter/submillimeter Array (ALMA) observed the earliest combined signals of oxygen, carbon, and dust from a galaxy in the Universe, 13 billion years ago. By comparing the different signals, the team determined that the galaxy is, in fact, two merging galaxies, making it the earliest example of merging galaxies yet discovered.

Takuya Hashimoto at Waseda University, Japan, and his team used ALMA to observe B14-65666, an object located 13 billion light-years away in the constellation Sextans. Because of the finite speed of light, the signals we receive from B14-65666 today had to travel for 13 billion years to reach us. In other words, they show us the image of what the galaxy looked like 13 billion years ago, less than 1 billion years after the Big Bang.

ALMA achieved the earliest observation of radio emissions from oxygen, carbon, and dust in B14-65666. The detection of multiple signals allows astronomers to retrieve complementary information.

Data analysis showed that the emissions are divided into two blobs. Previous observations with the Hubble Space Telescope (HST) had revealed two-star clusters in B14-65666. Now, with the three emission signals detected by ALMA, the team was able to show that the two blobs do in-fact form a single system, but with different speeds; which indicates that the blobs are two merging galaxies. The earliest known example of merging galaxies. The research team estimated that the total stellar mass of B14-65666 is less than 10% that of the Milky Way, meaning that it’s in its earliest phases of evolution. Despite its youth, B14-65666 is producing stars 100 times more actively than the Milky Way. Such active star-formation rate is another signature of galactic mergers because the gas compression in colliding galaxies naturally leads to bursty star-formation.

“With rich data from ALMA and HST, combined with advanced data analysis, we could put the pieces together to show that B14-65666 is a pair of merging galaxies in the earliest era of the Universe,” explains Hashimoto. “Detection of radio waves from three components in such a distant object demonstrates ALMA’s high capability to investigate the distant Universe.”

Present galaxies like our Milky Way have experienced countless, often violent, mergers. Sometimes a more massive galaxy swallowed a smaller one. In rare cases, galaxies with similar sizes merged to form a new, larger galaxy. Mergers are essential for galaxy evolution, attracting many astronomers eager to trace back them.

“Our next step is to search for nitrogen, another major chemical element, and even the carbon monoxide molecule,” said Akio Inoue, a professor at Waseda University. “Ultimately, we hope to observationally understand the circulation and accumulation of elements and material in the context of galaxy formation and evolution.”

These observation results were published as T. Hashimoto et al. “’Big Three Dragons’: a z = 7.15 Lyman Break Galaxy Detected in [OIII] 88 um, [CII] 158 um, and Dust Continuum with ALMA” in the Publications of the Astronomical Society of Japan on June 18, 2019.

The research team members are: Takuya Hashimoto (Waseda University/Osaka Sangyo University/National Astronomical Observatory of Japan), Akio Inoue (Waseda University/Osaka Sangyo University), Ken Mawatari (Osaka Sangyo University/The University of Tokyo), Yoichi Tamura (Nagoya University), Hiroshi Matsuo (National Astronomical Observatory of Japan/SOKENDAI), Hisanori Furusawa (National Astronomical Observatory of Japan), Yuichi Harikane (The University of Tokyo), Takatoshi Shibuya (Kitami Institute of Technology), Kirsten K. Knudsen (Chalmers University of Technology), Kotaro Kohno (The University of Tokyo), Yoshiaki Ono (The University of Tokyo), Erik Zackrisson (Uppsala University), Takashi Okamoto (Hokkaido University), Nobunari Kashikawa (National Astronomical Observatory of Japan/SOKENDAI/ The University of Tokyo), Pascal A. Oesch (University of Geneva), Masami Ouchi (The University of Tokyo/National Astronomical Observatory of Japan), Kazuaki Ota (Kyoto University), Ikkoh Shimizu (Osaka University), Yoshiaki Taniguchi (The Open University of Japan), Hideki Umehata (The Open University of Japan/RIKEN), Darach Watson (University of Copenhagen).

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: “New ALMA Image Reveals Migrating Planet in Protoplanetary Disk”

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

From ALMA

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

ALMA observation of HD169142 which shows an outer region composed of thin rings and a double gap. These fine structures had never seen before in the outer parts of a disk with a deep chasm which severs the protoplanetary environment into inner and outer regions. On the other hand, the ALMA high-resolution image also reveals a bright inner ring with signs of being subject to dynamical perturbations. Solar system size approximated by Pluto’s orbit is shown for comparison. Credit: N. Lira – ALMA (ESO/NAOJ/NRAO); S. Pérez – USACH/UChile.

Comparison between ALMA image and theoretical simulation of the protoplanetary disk in HD169142. Simulated image of a planet with ten times the mass of Earth, sculpting the outer regions of a protoplanetary disk. The fine rings are composed of dust particles which are trapped into concentric structures by pressure waves excited during the interaction between the planet and the disk. Credit: N. Lira – ALMA (ESO/NAOJ/NRAO); S. Pérez – USACH/UChile.

Labelled ALMA image describing the structure of the protoplanetary disk in HD169142. Credit: N. Lira – ALMA (ESO/NAOJ/NRAO); S. Pérez – USACH/UChile.

A new high-resolution image from the Atacama Large Millimeter/submillimeter Array (ALMA) features a protoplanetary disk with an isolated outer region composed of an intricate system of thin rings and gaps, instead of the wide and smooth ring expected for these disks. The isolation of this never seen before structures allowed a research team to explain it with a straightforward interpretation: a single, migrating planet ten times the mass of Earth sculpting the dust particles into multiple narrow rings.

Finding direct connections between the gaps seen in protoplanetary disks and the properties of planets opens a new window to investigate a population of young planets that are exceedingly difficult to detect with any other method.

ALMA has seen a plethora of rings and gaps in almost all protoplanetary disks it has observed at high resolution, yet the origins of these structures remain a matter of intense debate. As the quality of the observations increases, the ringed structures grow in number and complexity, challenging a simple interpretation based on planetary origins. The new ALMA observations of HD169142, a protoplanetary disk 370 light-years away in the constellation of Sagittarius, allowed a team led by Sebastian Perez, from University of Santiago (Chile) to explain the seemingly complex architecture of protoplanetary ring systems with the presence of a single low-mass planet.

Even though it was designed to avoid disks with evidence of deep gaps and holes, the DSHARP ALMA Large Program unveiled, less than a year ago, several new ring systems. In the absence of a clear gap that separates an outer region, the superposition of multiple rings due to several planets hampers simple and clear explanations such as that found for HD169142. This particular ring system thus allows a proof of concept to interpret the detailed architecture of the outer region of protoplanetary disks, with low mass planet formation of mini-Neptune’s size. The fact that the middle ring is closer to the inner ring is the first evidence for planetary migration in disk observations. The planet moves closer to the star, shrinking its orbit, while shepherding the middle ring with it.

“The high-fidelity of ALMA helped us reveal unexpected substructure in the outer ring of a system thought to have no narrow rings” explains Sebastian Pérez, from Universidad de Santiago, and lead author of this research. “The community has made great progress on interpreting these sharp rings seen in young planetary systems. Here, one small planet interacting with tiny dust particles can reproduce these rings in isolation, revealing its properties in an indirect way. This one and other similar experiments open new possibilities of characterization of super young extra-solar planets.”

Science paper:
Dust Unveils the Formation of a Mini-Neptune Planet in a Protoplanetary Ring
[The Astronomical Journal]

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: “Cool, Nebulous Ring around Milky Way’s Supermassive Black Hole”

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

From ALMA

5 June, 2019
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 impression of ring of cool, interstellar gas surrounding the supermassive black hole at the center of the Milky Way. New ALMA observations reveal this structure for the first time. Credit: NRAO/AUI/NSF; S. Dagnello

ALMA image of the disk of cool hydrogen gas flowing around the supermassive black hole at the center of our galaxy. The colors represent the motion of the gas relative to Earth: the red portion is moving away, so the radio waves detected by ALMA are slightly stretched, or shifted, to the “redder” portion of the spectrum; the blue color represents gas moving toward Earth, so the radio waves are slightly scrunched, or shifted, to the “bluer” portion of the spectrum. Credit: ALMA (ESO/NAOJ/NRAO), E.M. Murchikova; NRAO/AUI/NSF, S. Dagnello

New ALMA observations reveal a never-before-seen disk of cold, interstellar gas wrapped around the supermassive black hole at the center of the Milky Way. This nebulous disk gives astronomers new insights into the workings of accretion: the siphoning of material onto the surface of a black hole. The results are published in the journal Nature.

Through decades of study, astronomers have developed a clearer picture of the chaotic and crowded neighborhood surrounding the supermassive black hole at the center of the Milky Way. Our galactic center is approximately 26,000 light-years from Earth and the supermassive black hole there, known as Sagittarius A* (A “star”), is 4 million times the mass of our Sun.

SgrA* NASA/Chandra supermassive black hole at the center of the Milky Way

SO-2 and SO-38 circle SGR A*Image UCLA Galactic Center Groupe via S. Sakai and Andrea Ghez at Keck Observatory

We now know that this region is brimming with roving stars, interstellar dust clouds, and a large reservoir of both phenomenally hot and comparatively colder gases. These gasesare expected toorbit the black hole in a vast accretion disk that extends a few tenths of a light-year from the black hole’s event horizon.

Until now, however, astronomers have only been able to image the tenuous, hot portion of this accreting gas, which forms a roughly spherical flow and showed no obvious rotation. Its temperature is estimated to be a blistering 10 million degrees Celsius (18 million degrees Fahrenheit), or about halfthe temperature found at the core of our Sun. At this temperature, the gas glows fiercely in X-ray light, allowing it to be studied by space-based X-ray telescopes, down to scale of about a tenth of a light-year from the black hole.

In addition to this hot, glowing gas, previous observations with millimeter-wavelength telescopes have detected a vast store of comparatively cooler hydrogen gas (nearly10 thousand degrees Celsius or 18,000 degrees Fahrenheit) within few light years around the black hole. The contributionof this cooler gas to the accretion flow onto the back hole was previously unknown.

Although our galactic center black hole is relatively quiet,the radiation around it is strongenough to cause hydrogen atoms to continually lose and recombine with their electrons. This recombination produces a distinctive millimeter-wavelength signal, which is capable of reaching the Earth with very little losses on the way.With its remarkable sensitivity and powerful ability to see fine details, the Atacama Large Millimeter/submillimeter Array (ALMA)was able to detect this faint radio signal and produce the first-ever image of the cooler gas disk surrounding the Milky Way’s supermassive black hole at only about a hundredth of a light-year away, or about 1000 times the distance from the Earth to the Sun.These observations enabled the astronomers both to map the location and trace the motion of this gas.The researchers estimate that the amount of hydrogen in this cool disk is about one tenth the mass of Jupiter, or one ten-thousandth of the mass of the Sun.

By mapping the shifts in wavelengths of this radio light due to the Doppler effect (light from objects moving toward the Earth is slightly shifted to the “bluer” portion of the spectrum while light from objects moving away is slightly shifted to the “redder” portion), the astronomers could clearly see that the gas is rotatingaround the black hole. This information will provide new insights into the ways that black holes devour matter and the complex interplay between a black hole and its galactic neighborhood.

“We were the first to image this elusive disk and study its rotation,” said Elena Murchikova, a member in astrophysics at the Institute for Advanced Study in Princeton, New Jersey.“We are also probing accretion onto the black hole. This is important because this is our closest supermassive black hole. Even so, we still have no good understanding of how its accretion works. We hope these new ALMA observations will help the black hole give up some of its secrets.”

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: “ALMA Discovers Aluminum around a Young Star”

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

From ALMA

16 May, 2019

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

ALMA image of the distributions of AlO molecules (color) and warm dust particles (contours). The molecular outflow (not shown in this image) extends from the center to the top-left and bottom-right. Credit: ALMA (ESO/NAOJ/NRAO), Tachibana et al.

Researchers using ALMA data discovered an aluminum-bearing molecule for the first time around a young star. Aluminum-rich inclusions found in meteorites are some of the oldest solid objects formed in the Solar System, but their formation process and stage is still poorly linked to star and planet formation. The discovery of aluminum oxide around a young star provides a crucial chance to study the initial formation process of meteorites and planets like the Earth.

Disks of gas surround young stars. Some of the gas condenses into dust grains which then stick together to form more substantial objects, building up to form meteors, planetesimals, and eventually planets. Understanding the formation of these first solid objects is essential for understanding everything which follows.

Shogo Tachibana, a professor at the University of Tokyo/Japan Aerospace Exploration Agency (JAXA), and his team analyzed the ALMA (Atacama Large Millimeter/submillimeter Array) data for Orion KL Source I, a massive young protostar, and found distinctive radio emissions from aluminum oxide (AlO) molecules. This is the first unambiguous detection of AlO around a young star.

“Aluminum oxide played a significant role in the formation of the oldest material in the Solar System,” says Tachibana “Our discovery will contribute to the understanding of material evolution in the early Solar System.”

Interestingly, the radio emissions from the AlO molecules are concentrated in the launching points of the outflows from the rotating disk around the protostar. In contrast, other molecules such as silicon monoxide (SiO) have been detected in a broader area in the outflow. Typically, the temperature is higher at the base of the outflows and lower in the downstream gas. “Non-detection of gas-phase AlO downstream indicates that the molecules have condensed into solid dust particles in the colder regions,” explains Tachibana. “Molecules can emit their distinctive radio signals in gas-phase, but not in solid-phase.”

ALMA’s detection of AlO in the hot base of the outflow suggests that the molecules are formed in hot regions close to the protostar. Once moved to colder areas, AlO would be captured in dust particles which can become aluminum-rich dust, like the oldest solid in the Solar System, and further the building blocks for planets.

The team will now observe other protostars looking for AlO. Combining the new results with data from meteorites and sample return missions like JAXA’s Hayabusa2 will provide essential insights into the formation and evolution of our Solar System and other planetary systems.
Additional Information

These observation results were published as Tachibana et al. “Spatial distribution of AlO in a high mass protostar candidate Orion Source I” in The Astrophysical Journal Letters on April 24, 2019.

The research team members are: Shogo Tachibana (The University of Tokyo), Takafumi Kamizuka (The University of Tokyo), Tomoya Hirota (National Astronomical Observatory of Japan / SOKENDAI), Nami Sakai (RIKEN), Yoko Oya (The University of Tokyo), Aki Takigawa (Kyoto University), and Satoshi Yamamoto (The University of Tokyo)

This research was supported by MEXT/JSPS KAKENHI (Nos. 25108002, 25108005, and 17K05398).

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.