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.

From ALMA: “Spiraling giants: witnessing the birth of a massive binary star system”

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

From ALMA

18 March, 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

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

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’s view of the IRAS-07299 star-forming region and the massive binary system at its center. The background image shows dense, dusty streams of gas (shown in green) that appear to be flowing towards the center. Gas motions, as traced by the methanol molecule, that are towards us are shown in blue; motions away from us in red. The inset image shows a zoom-in view of the massive forming binary, with the brighter, primary protostar moving toward us is shown in blue and the fainter, secondary protostar moving away from us shown in red. The blue and red dotted lines show an example of orbits of the primary and secondary spiraling around their center of mass (marked by the cross).

Movie composed of images taken by ALMA showing the gas streams, as traced by the methanol molecule, with different line-of-sight color-coded velocities, around the massive binary protostar system. The grey background image shows the overall distribution, from all velocities, of dust emission from the dense gas streams.

Scientists from the RIKEN Cluster for Pioneering Research in Japan,the Chalmers University of Technology in Sweden,and the University of Virginia in the USA and collaborators used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe a molecular cloud that is collapsing to form two massive protostars that will eventually become a binary star system.

While it is known that most massive stars possess orbiting stellar companions it has been unclear how this comes about – for example, are the stars born together from a common spiraling gas disk at the center of a collapsing cloud, or do they pair up later by chance encounters in a crowded star cluster.

Understanding the dynamics of forming binaries has been difficult because the protostars in these systems are still enveloped in a thick cloud of gas and dust that prevents most light from escaping. Fortunately, it is possible to see them using radio waves, as long as they can be imaged with sufficiently high spatial resolution.

In the current research, published in Nature Astronomy, the researchers led by Yichen Zhang of the RIKEN Cluster for Pioneering Research and Jonathan C. Tan at the Chalmers University,and the University of Virginia, used ALMA to observe, at high spatial resolution, a star-forming region known as IRAS07299-1651, which is located 1.68 kiloparsecs, or about 5,500 light years, away.

The observations showed that already at this early stage, the cloud contains two objects, a massive “primary” central star and another “secondary” forming star, also of high mass. For the first time, the research team was able to use these observations to deduce the dynamics of the system. The observations showed that the two forming stars are separated by a distance of about 180 astronomical units—a unit approximately the distance from the earth to the sun. Hence, they are quite far apart. They are currently orbiting each other with a period of at most 600 years and have a total mass at least 18 times that of our Sun.

According to Zhang, “This is an exciting finding because we have long been perplexed by the question of whether stars form into binaries during the initial collapse of the star-forming cloud or whether they are created during later stages. Our observations clearly show that the division into binary stars takes place early on, while they are still in their infancy.”

Another finding of the study was that the binary stars are being nurtured from a common disk fed by the collapsing cloud and favoring a scenario in which the secondary star of the binary formed as a result of fragmentation of the disk originally around the primary. This allows the initially smaller secondary protostar to “steal” infalling matter from its sibling and eventually they should emerge as quite similar “twins”.

Tan adds, “This is an important result for understanding the birth of massive stars. Such stars are important throughout the universe, not least for producing, at the ends of their lives, the heavy elements that make up our Earth and are in our bodies.”

Zhang concludes, “What is important now is to look at other examples to see whether this is a unique situation or something that is common for the birth of all massive stars.”

Additional Information

RIKEN is Japan’s largest research institute for basic and applied research. Over 2500 papers by RIKEN researchers are published every year in leading scientific and technology journals covering a broad spectrum of disciplines including physics, chemistry, biology, engineering, and medical science. RIKEN’s research environment and a strong emphasis on interdisciplinary collaboration and globalization have earned a worldwide reputation for scientific excellence.

At the RIKEN Pioneering Research Cluster, outstanding researchers with rich research achievements and strong leadership abilities serve as leaders of Chief Scientist Laboratories, from where they carry out innovative fundamental research, pioneer new research fields, and carry on research that crosses disciplinary and organizational barriers.

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 Observes the Formation Sites of Solar-System-like Planets”

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

From ALMA

2019.03.11

Researchers have spotted the formation sites of planets around a young star resembling our Sun. Two rings of dust around the star, at distances comparable to the asteroid belt and the orbit of Neptune in our Solar System, suggest that we are witnessing the formation of a planetary system similar to our own.

The Solar System is thought to have formed from a cloud of cosmic gas and dust 4.6 billion years ago. By studying young planetary systems forming around other stars, astronomers hope to learn more about our own origins.

Tomoyuki Kudo, an astronomer at the National Astronomical Observatory of Japan (NAOJ), and his team observed the young star DM Tau using the Atacama Large Millimeter/submillimeter Array (ALMA). Located 470 light-years away in the constellation Taurus, DM Tau is about half the mass of the Sun and estimated to be three to five million years old.

“Previous observations inferred two different models for the disk around DM Tau,” said Kudo. “Some studies suggested the radius of the ring is about where the Solar System’s asteroid belt would be. Other observations put the size out where Neptune would be. Our ALMA observations provided a clear answer: both are right. DM Tau has two rings, one at each location.”

The researchers found a bright patch in the outer ring. This indicates a local concentration of dust, which would be a possible formation site for a planet like Uranus or Neptune.

“We are also interested in seeing the details in the inner region of the disk, because the Earth formed in such an area around the young Sun,” commented Jun Hashimoto, a researcher at the Astrobiology Center, Japan. “The distribution of dust in the inner ring around DM Tau will provide crucial information to understand the origin of planets like Earth.”

ALMA image of the dusty disk around the young star DM Tau. You can see two concentric rings where planets may be forming. Credit: ALMA (ESO/NAOJ/NRAO), Kudo et al.

Artist’s impression of the disk around a young star DM Tau. Credit: NAOJ

Paper and the research team
These results were published as Kudo et al. “A Spatially Resolved au-scale Inner Disk around DM Tau” in The Astrophysical Journal in November 2018 and presented at the annual meeting of the Astronomical Society of Japan in March 2019.

The research team members are:
Tomoyuki Kudo (National Astronomical Observatory of Japan), Jun Hashimoto (Astrobiology Center), Takayuki Muto (Kogakuin University), Hauyu Baobab Liu (European Southern Observatory), Ruobing Dong (University of Victoria), Yasuhiro Hasegawa (California Institute of Technology)

This research was supported by JSPS KAKENHI (Nos. 17K14258, 17K14244, 26800106, 15H02074, 17H01103）and NASA Jet Propulsion Laboratory

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: “Hiding Black Hole Found”

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

From ALMA

28 February, 2019

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

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

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 gas cloud swirling around a black hole. Credit: NAOJ

Astronomers have detected a stealthy black hole from its effects on an interstellar gas cloud. This intermediate mass black hole is one of over 100 million quiet black holes expected to be lurking in our galaxy. These results provide a new method to search for other hidden black holes and help us understand the growth and evolution of black holes.

Black holes are objects with such strong gravity that everything, including light, is sucked in and cannot escape. Because black holes do not emit light, astronomers must infer their existence from the effects their gravity produce in other objects. Black holes range in mass from about 5 times the mass of the Sun to supermassive black holes millions of times the mass of the Sun. Astronomers think that small black holes merge and gradually grow into large ones, but no one had ever found an intermediate mass, hundreds or thousands of times the mass of the Sun.

A research team led by Shunya Takekawa at the National Astronomical Observatory of Japan noticed HCN–0.009–0.044, a gas cloud moving strangely near the center of the Galaxy 25,000 light-years away from Earth in the constellation Sagittarius. They used ALMA (Atacama Large Millimeter/submillimeter Array) to perform high resolution observations of the cloud and found that it is swirling around an invisible massive object.

Takekawa explains, “Detailed kinematic analyses revealed that an enormous mass, 30,000 times that of the Sun, was concentrated in a region much smaller than our Solar System. This and the lack of any observed object at that location strongly suggests an intermediate-mass black hole. By analyzing other anomalous clouds, we hope to expose other quiet black holes. ”

Tomoharu Oka, a professor at Keio University and coleader of the team, adds, “It is significant that this intermediate mass black hole was found only 20 light-years from the supermassive black hole at the Galactic center. In the future, it will fall into the supermassive black hole; much like gas is currently falling into it. This supports the merger model of black hole growth.”

These results were published as Takekawa et al. “Indication of Another Intermediate-mass Black Hole in the Galactic Center” in The Astrophysical Journal Letters on January 20, 2019.

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 Differentiates Two Birth Cries from a Single Star”

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

From ALMA

26 February, 2019

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

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

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

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

ALMA image of the protostar MMS5/OMC-3. The protostar is located at the center and the gas streams are ejected to the east and west (left and right). The slow outflow is shown in orange and the fast jet is shown in blue. It is obvious that the axes of the outflow and jet are misaligned. Credit: ALMA (ESO/NAOJ/NRAO), Matsushita et al.

Astronomers have unveiled the enigmatic origins of two different gas streams from a baby star. Using ALMA, they found that the slow outflow and the high speed jet from a protostar have misaligned axes and that the former started to be ejected earlier than the latter. The origins of these two flows have been a mystery, but these observations provide telltale signs that these two streams were launched from different parts of the disk around the protostar.

Stars in the Universe have a wide range of masses, ranging from hundreds of times the mass of the Sun to less than a tenth of that of the Sun. To understand the origin of this variety, astronomers study the formation process of the stars, that is the aggregation of cosmic gas and dust.

Baby stars collect the gas with their gravitational pull, however, some of the material is ejected by the protostars. This ejected material forms a stellar birth cry which provides clues to understand the process of mass accumulation.

Yuko Matsushita, a graduate student at Kyushu University and her team used ALMA to observe the detailed structure of the birth cry from the baby star MMS5/OMC-3 and found two different gaseous flows: a slow outflow and a fast jet. There have been a handful of examples with two flows seen in radio waves, but MMS5/OMC-3 is exceptional.

“Measuring the Doppler shift of the radio waves, we can estimate the speed and lifetime of the gas flows,” said Matsushita, the lead author of the research paper that appeared in the Astrophysical Journal. “We found that the jet and outflow were launched 500 years and 1300 years ago, respectively. These gas streams are quite young.”

More interestingly, the team found that the axes of the two flows are misaligned by 17 degrees. The axis of the flows can be changed over long time periods due to the precession of the central star. But in this case, considering the extreme youth of the gas streams, researchers concluded that the misalignment is not due to precession but is related to the launching process.

There are two competing models for the formation mechanism of the protostellar outflows and jets. Some researchers assume that the two streams are formed independently in different parts of the gas disk around the central baby star, while others propose that the collocated jet is formed first, then it entrains the surrounding material to form the slower outflows. Despite extensive research, astronomers had not yet reached a conclusive answer.

A misalignment in the two flows could occur in the ‘independent model,’ but is difficult in the ‘entrainment model.’ Moreover, the team found that the outflow was ejected considerably earlier than the jet. This clearly backs the ‘independent model.’

“The observation well matches the result of my simulation,” said Masahiro Machida, a professor at Kyushu University. A decade ago, he performed pioneering simulation studies using a supercomputer operated by the National Astronomical Observatory of Japan. In the simulation, the wide-angle outflow is ejected from the outer area of the gaseous disk around a prototar, while the collimated jet is launched independently from the inner area of the disk. Machida continues, “An observed misalignment between the two gas streams may indicate that the disk around the protostar is warped.”

“ALMA’s high sensitivity and high angular resolution will enable us to find more and more young, energetic outflow-and-jet-systems like MMS 5/OMC-3,” said Satoko Takahashi, an astronomer at the National Astronomical Observatory of Japan and the Joint ALMA Observatory and co-author of the paper. “They will provide clues to understand the driving mechanisms of outflows and jets. Moreover studying such objects will also tell us how the mass accretion and ejection processes work at the earliest stage of star formation.”
Additional Information

These observation results were published as Matsushita et al. “Very Compact Extremely High Velocity Flow toward MMS 5 / OMC-3 Revealed with ALMA” in The Astrophysical Journal issued in February 2019.

The research team members are:

Yuko Matsushita (Kyushu University), Satoko Takahashi (Joint ALMA Observatory/National Astronomical Observatory of Japan/SOKENDAI), Masahiro Machida (Kyushu University), and Koji Tomisaka (National Astronomical Observatory of Japan/SOKENDAI)

This research was supported by JSPS KAKENHI (No. 17K05387, 17H06360, 17H02869, 15K05032) and the Science Visitor Program of the Joint ALMA Observatory.

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: “Liberal Sprinkling of Salt Discovered around a Young Star”

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

From ALMA

7 February, 2019

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

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

Artist impression of Orion Source I, a young, massive star about 1,500 light-years away. New ALMA observations detected a ring of salt — sodium chloride, ordinary table salt — surrounding the star. This is the first detection of salts of any kind associated with a young star. The blue region (about 1/3 the way out from the center of the disk) represents the region where ALMA detected the millimeter-wavelength “glow” from the salts. Credit: NRAO/AUI/NSF; S. Dagnello

ALMA image of the salty disk surrounding the young, massive star Orion Source I (blue ring). It is shown in relation to the Orion Molecular Cloud 1, a region of explosive starbirth. The background near infrared image was taken with the Gemini Observatory. Credit: ALMA (NRAO/ESO/NAOJ); NRAO/AUI/NSF; Gemini Observatory/AURA

Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

A team of astronomers and chemists using the Atacama Large Millimeter/submillimeter Array (ALMA) has detected the chemical fingerprints of sodium chloride (NaCl) and other similar salty compounds emanating from the dusty disk surrounding Orion Source I, a massive, young star in a dusty cloud behind the Orion Nebula.

“It’s amazing we’re seeing these molecules at all,” said Adam Ginsburg, a Jansky Fellow of the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, and lead author of a paper accepted for publication in The Astrophysical Journal. “Since we’ve only ever seen these compounds in the sloughed-off outer layers of dying stars, we don’t fully know what our new discovery means. The nature of the detection, however, shows that the environment around this star is very unusual.”

To detect molecules in space, astronomers use radio telescopes to search for their chemical signatures – telltale spikes in the spread-out spectra of radio and millimeter-wavelength light. Atoms and molecules emit these signals in several ways, depending on the temperature of their environments.

The new ALMA observations contain a bristling array of spectral signatures – or transitions, as astronomers refer to them – of the same molecules. To create such strong and varied molecular fingerprints, the temperature differences where the molecules reside must be extreme, ranging anywhere from 100 kelvin to 4,000 kelvin (about -175 Celsius to 3700 Celsius). An in-depth study of these spectral spikes could provide insights about how the star is heating the disk, which would also be a useful measure of the luminosity of the star.

“When we look at the information ALMA has provided, we see about 60 different transitions – or unique fingerprints – of molecules like sodium chloride and potassium chloride coming from the disk. That is both shocking and exciting,” said Brett McGuire, a chemist at the NRAO in Charlottesville, Virginia, and co-author on the paper.

The researchers speculate that these salts come from dust grains that collided and spilled their contents into the surrounding disk. Their observations confirm that the salty regions trace the location of the circumstellar disk.

“Usually when we study protostars in this manner, the signals from the disk and the outflow from the star get muddled, making it difficult to distinguish one from the other,” said Ginsburg. “Since we can now isolate just the disk, we can learn how it is moving and how much mass it contains. It also may tell us new things about the star.”

The detection of salts around a young star is also of interest to astronomers and astrochemists because some of constituent atoms of salts are metals – sodium and potassium. This suggests there may be other metal-containing molecules in this environment. If so, it may be possible to use similar observations to measure the amount of metals in star-forming regions. “This type of study is not available to us at all presently. Free-floating metallic compounds are generally invisible to radio astronomy,” noted McGuire.

The salty signatures were found about 30 to 60 astronomical units (AU, or the average distance between the Earth and the Sun) from the host stars. Based on their observations, the astronomers infer that there may be as much as one sextillion (a one with 21 zeros after it) kilograms of salt in this region, which is roughly equivalent to the entire mass of Earth’s oceans.

“Our next step in this research is to look for salts and metallic molecules in other regions. This will help us understand if these chemical fingerprints are a powerful tool to study a wide range of protoplanetary disks, or if this detection is unique to this source,” said Ginsburg. “In looking to the future, the planned Next Generation VLA would have the right mix of sensitivity and wavelength coverage to study these molecules and perhaps use them as tracers for planet-forming disks.”

Orion Source I formed in the Orion Molecular Cloud I, a region of explosive starbirth previously observed with ALMA. “This star was ejected from its parent cloud with a speed of about 10 kilometers per second around 550 years ago,”1 said John Bally, an astronomer at the University of Colorado and co-author on the paper. “It is possible that solid grains of salt were vaporized by shock waves as the star and its disk were abruptly accelerated by a close encounter or collision with another star. It remains to be seen if salt vapor is present in all disks surrounding massive protostars, or if such vapor traces violent events like the one we observed with ALMA.”

1. Light from this object took about 1,500 years to reach Earth. Astronomers are seeing it as if looking through that window of time, which reveals how it looked 550 years after it was ejected from its stellar nursery.

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.