Tagged: Millimeter/submillimeter astronomy Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 4:01 pm on April 12, 2018 Permalink | Reply
    Tags: , ALMA Deepens Mystery about the relation between Supermassive Black Holes and their Host Galaxies, , , , , Millimeter/submillimeter astronomy,   

    From ALMA: “ALMA Deepens Mystery about the relation between Supermassive Black Holes and their Host Galaxies” 

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

    ALMA

    20 February, 2018 [This one got away from me.]

    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

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

    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

    Science paper
    No Sign of Strong Molecular Gas Outflow in an Infrared-bright Dust-obscured Galaxy with Strong Ionized-gas Outflow
    The Astrophysical Journal

    Using the Atacama Large Millimeter/submillimeter Array (ALMA) to observe an active galaxy with a strong ionized gas outflow from the galactic center, astronomers have obtained a result making astronomers even more puzzled: an unambiguous detection of carbon monoxide (CO) gas associated with the galactic disk. However, they have also found that the CO gas which settles in the galaxy is not affected by the strong ionized gas outflow launched from the galactic center.

    According to a popular scenario explaining the formation and evolution of galaxies and supermassive black holes, radiation from galactic centers, where supermassive black holes are, can significantly influence the molecular gas (such as CO) and the star formation activities of the galaxies.

    ALMA result shows that the ionized gas outflow driven by the supermassive black hole does not necessarily affect its host galaxy. This result “has made the co-evolution of galaxies and supermassive black holes more puzzling,” explains Dr. Yoshiki Toba from the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA, Taiwan), and main author of this research. “The next step is looking into more data of this kind of galaxies. That is crucial for understanding the full picture of the formation and evolution of galaxies and supermassive black holes”.

    Answering the question “How did galaxies form and evolve during the 13.8-billion-year history of the universe?” has been one top issue in modern astronomy. Studies already revealed that almost all massive galaxies harbor a supermassive black hole at their centers. In recent findings, studies further showed the tight correlation between the mass of black holes and those of their host galaxies. This correlation suggests that supermassive black holes and their host galaxies have evolved together and they closely interacted each other as they grew, as known as the co-evolution of galaxies and supermassive black holes.

    The gas outflow driven by a supermassive black hole at the galactic center recently has become the focus of attention as it possibly is playing a key role in the co-evolution of galaxies and black holes. A widely accepted idea has described this phenomenon as the intense radiation from the galactic center in which is the supermassive black hole ionizes [1] the surrounding gas, even affecting the molecular gas that is the ingredient of star formation. The strong radiation activates [2] or suppresses [3] the star formation of galaxies. However, “we astronomers do not understand the real relation between the activity of supermassive black holes and star formation in galaxies,” says Tohru Nagao, Professor at Ehime University. “Therefore, many astronomers including us are eager to observe the real scene of the interaction between the nuclear outflow and the star-forming activities, for revealing the mystery of the co-evolution.”

    2
    Figure 1: Image of a DOG, WISE1029. The left and right panels show an optical image from the Sloan Digital Sky Survey (SDSS), and mid-infrared image from WISE, respectively. The image size is 30 square arcsecond (1 arcsecond is 1/3600 degree). It is clear that DOGs are faint in the optical, but are incredibly bright in the infrared. The SDSS spectrum indicates that strong ionized gas is outflowing toward us from WISE1029. Credit: Sloan Digital Sky Survey/NASA/JPL-Caltech

    Astronomers believe that DOGs harbor actively growing supermassive black holes in their nuclei [4]. In particular, one DOG (WISE1029+0501, hereafter WISE1029) is outflowing gas ionized by the intense radiation from its supermassive black hole. WISE1029 is known as an extreme case concerning ionized gas outflow, and this particular factor has motivated the researchers to see what happens to its molecular gas.

    By making use of ALMA’s outstanding sensitivity which is excellent in investigating properties of molecular gas and star-forming activities in galaxies, the team conducted their research by observing the CO and the cold dust of galaxy WISE1029 (Figure 2). After detailed analysis, surprisingly they found, there is no sign of significant molecular gas outflow. Furthermore, star-forming activity is neither activated nor suppressed. This indicates that a strong ionized gas outflow launched from the supermassive black hole in WISE1029 neither significantly affect the surrounding molecular gas nor the star formation.

    3
    Figure 2: Emission from carbon monoxide (left) and cold dust (right) in WISE1029 observed by ALMA. The image size is 3 square arcsecond. Credit: ALMA (ESO/NAOJ/NRAO), Toba et al.

    There have been many reports saying that the ionized gas outflow driven by the accretion power of a supermassive black hole has an enormous impact on surrounding molecular gas (e.g., *2,3). However, it is a rare case that there is no close interaction between ionized and molecular gas as the researchers are reporting this time. Yoshiki and its team’s result suggests that the radiation from a supermassive black hole does not always affect the molecular gas and star formation of its host galaxy.

    3
    Figure 3: A schematic view of the fact that an ionized gas outflow (green) driven by the central supermassive black hole does not affect the star formation of its host galaxy. This situation may occur if the ionized gas is outflowing perpendicularly to the molecular gas. Credit: ALMA (ESO/NAOJ/NRAO)

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

    3
    Figure 3: A schematic view of the fact that an ionized gas outflow (green) driven by the central supermassive black hole does not affect the star formation of its host galaxy. This situation may occur if the ionized gas is outflowing perpendicularly to the molecular gas. Credit: ALMA (ESO/NAOJ/NRAO)

    While their result is making the co-evolution of galaxies and supermassive black holes more puzzling, Yoshiki and his team are exciting about revealing the full picture of the scenario. He says that “understanding such co-evolution is crucial for astronomy. By collecting statistical data of this kind of galaxies and continuing in more follow-up observations using ALMA, we hope to reveal the truth.”
    Notes

    [1] It is a phenomenon where ultraviolet and X-ray radiations make a neutral gas plasma state.

    [2] See the ALMA news Black-Hole-Powered Jets Forge Fuel for Star Formation</em> on February 15, 2017

    [3] See the ALMA news Chaotic Turbulence Roiling ‘Most Luminous Galaxy’ in the Universe on February 18, 2016.

    [4] See the press release from Subaru Telescope Discovering Dust-Obscured Active Galaxies as They Grow</em> on August 26, 2015.
    Additional Information

    These observation results were published as Toba et al. No sign of strong molecular gas outflow in an infrared-bright dust-obscured galaxy with strong ionized-gas outflow in the Astrophysical Journal [link is above.] in December 2017.

    This research was conducted by:

    Yoshiki Toba (Academia Sinica), Shinya Komugi (Kogakuin University), Tohru Nagao (Ehime University), Takuji Yamashita (Ehime University), Wei-Hao Wang (Academia Sinica), Masatoshi Imanishi (National Astronomical Observatory of Japan), Ai-Lei Sun (Academia Sinica, now Johns Hopkins University).

    Advertisements
     
  • richardmitnick 5:24 pm on April 2, 2018 Permalink | Reply
    Tags: , , , , , , Millimeter/submillimeter astronomy, , Rings and Gaps in a Developing Planetary System   

    From CfA: “Rings and Gaps in a Developing Planetary System” 

    Harvard Smithsonian Center for Astrophysics


    Center For Astrophysics

    1
    A model of the dust ring around the young star Elias 24, produced from simulations based on new ALMA millimeter images of the system. The model finds that the dust was shaped by a planet with 70% of Jupiter’s mass located about 60 au from the star. Dipierro et al. 2018

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

    The discovery of an exoplanet has most often resulted from the monitoring of a star’s flicker (the transiting method) or its wobble (the radial velocity method).

    Planet transit. NASA/Ames

    Radial Velociity Method. ESO

    Discovery by direct imaging is rare because it is so difficult to spot a faint exoplanet hidden in the glare of its host star. The advent of the new generation of radio interferometers (as well as improvements in near-infrared imaging), however, has enabled the imaging of protoplanetary discs and, in the disc substructures, the inference of orbiting exoplanets. Gaps and ring-like structures are particularly fascinating clues to the presence or ongoing formation of planets.

    Rings of dust have already been identified in many protoplanetary systems from their infrared and submillimeter emission. The origin of these rings is debated. They might have formed from dust “pile-up,” dust settling, gravitational instabilities, or even from variations in the optical properties of the dust. Alternatively, the rings could result dynamically from the orbital motions of planets that have already developed or that are well on their way. Planets will induce waves in the dusty discs which, as they dissipate, can produce gaps or rings. Key to solving the problem is recognizing that different sized dust grains behave differently, with small grains being strongly coupled to the gas and so track the gas mass, whereas larger grains (millimeter-sized or larger) tend to follow pressure gradients and concentrate near gap edges.

    CfA astronomers Sean Andrews and David Wilner were members of a team of scientists who used the ALMA facility to image the dust around the young star Elias 24 with a resolution of about 28 au (one astronomical unit being about the average distance of the Earth from the Sun). The astronomers find evidence for gaps and rings and, assuming these are produced by an orbiting planet, they model the system allowing both the planet’s mass and location and the dust’s density distribution to evolve. Their best model explains the observations quite well: after about forty-four thousand years the inferred planet has a mass 70% of Jupiter’s mass and is located 61.7 au from the star. The result reinforces the conclusion that both gaps and rings are prevalent in a wide variety of young circumstellar disks, and signal the presence of orbiting planets.

    Science paper:
    Rings and gaps in the disc around Elias 24 revealed by ALMA .
    MNRAS

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

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

     
  • richardmitnick 1:38 pm on March 16, 2018 Permalink | Reply
    Tags: , ALMA - Breathless Science, , , , , , Millimeter/submillimeter astronomy,   

    From ESOblog: “Breathless Science” 

    ESO 50 Large

    ESOblog

    16 March 2018

    1
    On the Ground

    At a soaring altitude of 5100 metres above sea level, the ALMA Observatory is one of the world’s most extreme work environments. Athletes and hikers who climb this high usually move up slowly in altitude to adjust to the lower oxygen levels. But at ALMA, workers go from the Operations Support Facility (OSF) at 2900 metres up to the array of antennas at 5100 metres in less than an hour — and they go up and down daily. We spoke to Ivan Lopez, ALMA’s Safety Manager, to find out how to minimise the negative effects of high altitude on the health of workers.

    2
    Iván López

    Q: Tell us about your staff — what kinds of people work at ALMA and the OSF?

    A: We have on average 250 people at our observatory. From those, approximately 50 are exposed to intermittent hypoxia, which is a medical condition where the body does not get sufficient oxygen. We need all types of workers and their skills: from cleaning staff, to electrical and mechanical technicians, to a range of civil engineers, to our scientists. The astronomers who end up using ALMA data seldom need to work at the high site.

    Q: What are the conditions like for your staff?

    A: Our facilities in the Atacama Desert are essentially like small towns located in remote places, where the access to entertainment, leisure, medical care, and contact with loved ones is limited. This takes its toll on the sociological, psychological and personal development of our teams. But the environment is one of our biggest challenges. The ALMA site of is one of the driest on Earth, with very extreme weather and fast changes between conditions — we can have all four seasons in one day!

    Perhaps most importantly, we are confronted with rapid altitude changes that physiologically affect our workers’ bodies. Low oxygen levels make our work unsafe and more difficult. Since we must travel from 2900 to 5100 metres above sea level in just 45 minutes, we are exposed to hypoxia.

    3
    This panoramic view of the Chajnantor Plateau shows ALMA bathed in a spectacular sunset. It captures the feeling of solitude experienced at the ALMA site and the otherworldly appearance of the terrain.
    Credit: Y. Beletsky/ESO.

    Q: What is hypoxia and what effects does it have?

    A: Hypoxia is a deficiency in the amount of oxygen that reaches the body’s tissues. The severity of its effects depends on the length of exposure and the person’s physiology. We’ve been working with the University of Zurich in Switzerland, the University of Calgary in Canada, and the Universidad Católica del Norte in Chile to study the effects of hypoxia, as well as possible solutions for how to reduce these effects in our workers. It’s a great win-win for all of us. The medical researchers enjoy working with us — ALMA is like a natural laboratory for these studies due to its high altitude — and we, in turn, learn new information that we can use to take precautionary measures for our staff.

    4
    ALMA Transporter Operator Patricio Saavedra working with oxygen at 5000 metres. Credit: ESO/Max Alexander.

    In the latest round of studies in 2016, researchers examined our workers who volunteered over six weeks, examining their cognitive skills, sleep quality, breathing patterns, blood flow to the brain, and changes in blood flow between the heart and lungs. The studies are currently being reviewed and will be published this year. Among the many things we learned, we found out that hypoxia influences a worker’s quality of sleep, attention span, and short-term memory. This poses a real danger, as it negatively impacts the quality, productivity and safety of our workers and equipment, since many of our staff work on tasks that require a high level of concentration. This means that accident probability goes up since people are less alert.

    Q: Facing these risks, how do you ensure that staff working at ALMA and the OSF are safe?

    A: The results of these ongoing studies have made us change our daily programme, activities, and procedures to create a safer working environment. We’re currently making changes to our approach to safety and health, which has been used as a model across our facilities and Chile. We also carry out our High Altitude Medical Evaluation every year, which means that each worker gets a green light from a doctor more often than required by the Chilean authorities.

    _______________________________________________
    Among the many things we have changed, we have made the use of portable medical oxygen mandatory.
    _______________________________________________

    Among the many things we have changed, we have made the use of portable medical oxygen mandatory for all drivers from the 3000 metres above sea level and up, and for all workers on the Chajnantor Plateau where the antennas are located. The O2 tanks have evolved from big, bulky, heavy cylinders to smaller lightweight tanks made of carbon fibre. At the beginning, they are uncomfortable for the worker to use, but they get used to it — we’ve even designed backpacks to carry the O2 tank everywhere. Since we use liquified O2 that is very dry, we monitor our workers and provide nasal sprays to moisturise their airways.

    4
    The Array Operations Site (AOS) is the basecamp for the routine operations of the ALMA facility and the second highest building in the world. The AOS Technical Building houses the ALMA correlator — the highest-altitude supercomputer in the world. The air is so thin that the correlator’s fan system requires twice the usual airflow to keep it cool. Here Enrique Garcia, a correlator technician, examines the supercomputer system while breathing oxygen from a tank in his backpack. Credit: ESO/Max Alexander.

    The AOS (Array Operations Site) technical building on the Chajnantor plateau is also now permanently oxygenated (we have a liquid oxygen plant installed). It is also recommended that drivers going up and down our road have a copilot; that staff should work in teams of at least two; that supervisors should plan their work activities to follow exact procedures, with workers following bullet lists of small tasks; and that workers should limit the number of working hours at high altitude, optimising their shifts.

    We limit the time that all our workers, including contractors, spend at 5100 metres. Each of our staff work on a roster — eight days working at the site, and six days off work back at sea level. The day that they arrive, they are not allowed to go up to the high site. The second day of their shift, they are allowed to go up for just four hours; the third day for six hours; and from the fourth to the eighth day, a maximum of eight hours. No one is allowed to sleep at the high site.

    6
    This is no ordinary truck — it is an ALMA transporter, called Lore. At 20 metres long and 10 metres wide, this is one of a pair of custom-designed vehicles used to transport the 66 antennas that make up ALMA. Credit: Enrico Sacchetti/ESO.

    We have also increased our medical staff to have one registered nurse, stationed at the OSF, plus two paramedics on shift at all times. The paramedics go out on-site to perform field checks and constantly monitor the workers. A medical doctor visits twice a week to attend to all the needs of our workers. We also continuously train our staff in the latest developments on how to handle hypoxia and develop new strategies such a special diet and exercise program.

    Q: Why does a special diet need to be developed?

    A: High altitude can make it more difficult for the body to digest food. Ideally, our workers should have small snacks at different times of the day, such as dried fruits, almonds, nuts, fresh juice, power bars — mostly fast-release energy foods. We need to avoid heavy meals because they will take longer to digest at such heights. For example, right now we have removed soda beverages, broccoli, onions, cauliflower, turkey, beans and legumes from the meals. Managing our workers’ diets is actually one of the biggest challenges we have since the local workers are used to having big meals — something that has been rooted in their culture for generations.

    Q: Have any workers experienced severe altitude sickness, or has there been an altitude-related accident?

    A: Our programme has been very effective, so we have not had a serious or fatal incident related to hypoxia. But this does not mean that we have not had emergencies! We’ve had three serious emergencies where workers needed to be carried down to the nearby city of Calama. Around 15 visitors have also experienced minor hypoxia-related symptoms that needed attention.

    Luckily, our polyclinic staff have over 10 years of experience working at high altitudes and are regularly trained to deal with emergency situations. Our polyclinic is also equipped with three ambulances, two portable hyperbaric chambers, a cardiac arrest device, an emergency crash cart, and we have a contract with Telemedicina for the remote monitoring of heart illnesses. So we are very prepared to deal with emergencies.

    Q: What are the long-term effects of working at high altitude?

    A: The scientific literature has found that there are some long-term effects to hypoxia, mostly related to untreated issues or precautions have not been taken; but the studies performed so far have mostly been related to athletes or people who have suffered hypoxia-related accidents. There is very little available information on workers like ours in the long term. That is the reason why we are taking extreme care, continually monitoring our workers and partnering with universities to perform further studies.

    Q: Tell us about your role as Safety Manager.

    A: My office handles Safety, Health, Environment and Security at the ALMA Observatory, which includes managing the well-being of our people, the assessment of equipment, risk prevention, and our fire brigade team. We are also in charge of taking care of our environment by imposing regulations and resolutions based on environmental impact studies. We manage and develop ALMA’s health program and are also in charge of the management of the security contract.

    7
    Inside the Operations Support Facility (OSF), over 2000 metres below Chajnantor Plateau, ALMA test scientists go through the process of calibrating and testing the accuracy of an antenna. Credit: ESO/M. Alexander.

    Q: Can the extreme conditions affect the actual machinery of ALMA?

    A: Yes, and our engineers are constantly reviewing and adapting changes to cope with this. Antenna parts are being constantly modified and designed so we can meet with the requirement of our scientific clients, and many parts that were supposed to last a certain amount of years are actually lasting half of that time. The amount of time predicted for workers to carry out tasks has also been affected.

    Bear in mind that we are currently one of the few organisations in the world that has a wide array of equipment operating at these altitudes in such extreme conditions. Most information about how to function at these heights has not yet been shared by companies, mostly in the mining industry, who face similar challenges. So we are learning as we go. Our team has people with experience gained at the observatories in Hawaii and at APEX so we try to use their knowledge as a basis for many processes.

    Q: Has ESO shared its findings with the wider community?

    A: Yes, we have. There is not yet an international regulation for working at high altitude, so the data collected at ALMA is groundbreaking in the field and serves as a reference for ongoing medical studies. We are proud to say that the Chilean government has used our results to develop and change the current Chilean regulations on hypoxia, and we have participated in labour and health conferences to explain our approach to hypoxia. We are also an active part of the Lake Louise Hypoxia conference that is held every two years, where worldwide researchers show and explain their findings. One Peruvian company is using our health programme as a model for their own.

    Other observatories also face the same problems as they build their telescopes at high altitudes to escape the effects of atmospheric distortion. We have formed a group of safety managers from different observatories who meet periodically to share experiences and findings.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon

    Stem Education Coalition
    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Bloc Icon

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

    ESO LaSilla
    ESO/Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT
    VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO Vista Telescope
    ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO NTT
    ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT Survey telescope
    VLT Survey Telescope at Cerro Paranal with an elevation of 2,635 metres (8,645 ft) above sea level.

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres.

    ESO E-ELT
    ESO/E-ELT to be built at Cerro Armazones at 3,060 m.

    ESO APEX
    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert.

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

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

    ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level

    SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level

    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

     
  • richardmitnick 10:57 am on March 11, 2018 Permalink | Reply
    Tags: A young planet makes a scene, , , , , , , Millimeter/submillimeter astronomy,   

    From ALMA via Manu: “A young planet makes a scene” 


    Manu Garcia, a friend from IAC.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.

    26 February 2018

    CONTACTS
    Nicolas Lira
    Coordinator of Communications and Education
    Observatory ALMA, Santiago, Chile
    Phone: +56 2 2467 6519
    Mobile: +56 9 9445 7726
    Email: nicolas.lira@alma.cl

    Richard Hook
    Press Officer, European Southern Observatory
    Garching , Germany
    Phone: +49 89 3200 6655
    Mobile: +49 151 1537 3591
    Email: rhook@eso.org

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

    ALMA

    1
    A protoplanetary disk image captured by ALMA, AS 209

    Located in the young star – forming region of Ophiuchus, 410 light years from the Sun, a fascinating protoplanetary disk, named AS 209 , it is taking shape slowly. This wonderful image was captured using the high – resolution telescope ALMA, and reveals a curious pattern of rings and furrows in the dust surrounding a young star.

    Protoplanetary disks are dense gas and dust planes rotationally surrounding newly formed stars; on them is the stuff that can give rise to planets, moons , and other smaller bodies in orbit. With less than a million years, this system is very young, but already forming two grooves are defined on the disc.

    The outer groove is deep, broad and largely free of dust, which leads astronomers to think that there is a planet about the mass of Saturn orbiting (and it is about 800 light minutes from the central star and more than three times the distance between Neptune and the Sun!). As the planet shapes its path, the dust accumulates on the outer edge of its orbit, creating rings increasingly defined on the disk. The innermost groove is thinner and may have been formed by a smaller planet, but astronomers have raised the intriguing possibility that the great planet orbiting at greater distances has created both ways.

    This planet Saturn type, inferred so far from its parent star, raises fascinating questions about planetary formation at the edges of protoplanetary disks in particularly short time scales.

    Science paper:
    ALMA continuum observations of the protoplanetary disk AS 209,
    Astronomy & Astrophysics

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 10:23 am on March 7, 2018 Permalink | Reply
    Tags: ALMA Reveals Inner Web of Stellar Nursery, , , , , Millimeter/submillimeter astronomy,   

    From ALMA: “ALMA Reveals Inner Web of Stellar Nursery” 

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

    ALMA

    7 March 2018
    Alvaro Hacar González
    NWO-VENI Fellow – Leiden Observatory
    Leiden University, the Netherlands
    Email: hacar@strw.leidenuniv.nl

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

    1
    New data from the Atacama Large Millimeter/submillimeter Array (ALMA) and other telescopes have been used to create this stunning image showing a web of filaments in the Orion Nebula. These features appear red-hot and fiery in this dramatic picture, but in reality are so cold that astronomers must use telescopes like ALMA to observe them.

    This spectacular and unusual image shows part of the famous Orion Nebula, a star formation region lying about 1350 light-years from Earth. It combines a mosaic of millimetre-wavelength images from the Atacama Large Millimeter/submillimeter Array (ALMA) and the IRAM 30-metre telescope, shown in red, with a more familiar infrared view from the HAWK-I instrument on ESO’s Very Large Telescope, shown in blue.

    IRAM 30m Radio telescope, on Pico Veleta in the Spanish Sierra Nevada,, Altitude 2,850 m (9,350 ft)

    ESO HAWK-I on the ESO VLT

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)

    The group of bright blue-white stars at the upper-left is the Trapezium Cluster — made up of hot young stars that are only a few million years old.

    The wispy, fibre-like structures seen in this large image are long filaments of cold gas, only visible to telescopes working in the millimetre wavelength range. They are invisible at both optical and infrared wavelengths, making ALMA one of the only instruments available for astronomers to study them. This gas gives rise to newborn stars — it gradually collapses under the force of its own gravity until it is sufficiently compressed to form a protostar — the precursor to a star.

    The scientists who gathered the data from which this image was created were studying these filaments to learn more about their structure and make-up. They used ALMA to look for signatures of diazenylium gas, which makes up part of these structures. Through doing this study, the team managed to identify a network of 55 filaments.

    The Orion Nebula is the nearest region of massive star formation to Earth, and is therefore studied in great detail by astronomers seeking to better understand how stars form and evolve in their first few million years. ESO’s telescopes have observed this interesting region multiple times, and you can learn more about previous discoveries here, here, and here.

    This image combines a total of 296 separate individual datasets from the ALMA and IRAM telescopes, making it one of the largest high-resolution mosaics of a star formation region produced so far at millimetre wavelengths [1].
    Notes

    [1] Earlier mosaics of Orion at millimetre wavelengths had used single-dish telescopes, such as APEX.

    ESO/APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)

    The new observations from ALMA and IRAM use interferometry to combine the signals from multiple, widely-separated antennas to create images showing much finer detail.

    Science Paper:
    An ALMA study of the Orion Integral Filament: I. Evidence for narrow fibers in a massive cloud

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 6:19 pm on March 6, 2018 Permalink | Reply
    Tags: A Decade of Atmospheric Data Aids Black Hole Observers, , , , , , Millimeter/submillimeter astronomy, ,   

    From Eos: “A Decade of Atmospheric Data Aids Black Hole Observers” 

    AGU bloc

    AGU
    Eos news bloc

    Eos

    2 February 2018
    Kimberly M. S. Cartier

    1
    The Atacama Pathfinder Experiment (APEX) 12-meter telescope in Chile’s Atacama Desert, shown here, will join others to image the immediate surroundings of a black hole this April during an optimum observing period calculated by scientists using global weather data. Credit: European Southern Observatory/H. H. Heyer, CC BY 4.0

    A worldwide collaboration of radio astronomers called the Event Horizon Telescope (EHT) is taking a close look at the atmosphere here on Earth to get a better view of an elusive area of deep space.

    Event Horizon Telescope Array

    Arizona Radio Observatory
    Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

    ESO/APEX
    Atacama Pathfinder EXperiment

    CARMA Array no longer in service
    Combined Array for Research in Millimeter-wave Astronomy (CARMA)

    Atacama Submillimeter Telescope Experiment (ASTE)
    Atacama Submillimeter Telescope Experiment (ASTE)

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

    IRAM NOEMA interferometer
    Institut de Radioastronomie Millimetrique (IRAM) 30m

    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano

    CfA Submillimeter Array Hawaii SAO
    Submillimeter Array Hawaii SAO

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array, Chile

    South Pole Telescope SPTPOL
    South Pole Telescope SPTPOL

    Future Array/Telescopes

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    NSF CfA Greenland telescope

    Thanks to their recent modeling of the past 10 years of global atmospheric and weather data, they can now predict when their nine radio telescopes and arrays scattered around the world are most likely to have the clear view they need to make their extraordinary simultaneous observations.

    The scientists’ quarry is the perilous boundary of a black hole, called the event horizon, and the surrounding region of space. Their target is not just any black hole: It’s the hulking, supermassive black hole that lurks at the heart of the Milky Way.

    “You have to get all the participating observatories to collectively agree to give the EHT folks time on the sky when they ask for it…and that’s a big deal,” said Scott Paine, an astrophysicist at the Smithsonian Astrophysical Observatory (SAO) in Cambridge, Mass., who also happens to be an atmospheric scientist. “When an observatory commits several days to EHT to observe, we want the EHT to make good use of it, because it represents a significant investment for the observatory.”

    Trying to ensure that EHT scientists would make the most of valuable worldwide observing time, Paine advised that they approach the problem scientifically using global atmospheric records. Along with EHT director and SAO astrophysicist Sheperd Doeleman, he spearheaded the creation of a model that predicts the probability of good simultaneous observations at all sites using data gathered by the National Oceanic and Atmospheric Administration (NOAA). Using this new model, the EHT collaboration is coordinating a weeklong observing campaign that will take place this coming April.

    It’s not the first time the collaboration will peer at our galaxy’s central black hole, which is known as Sgr A* and weighs in at about 4 million times the mass of our Sun.

    SGR A* , the supermassive black hole at the center of the Milky Way. NASA’s Chandra X-Ray Observatory

    SgrA* NASA/Chandra

    The inaugural attempt took place in April 2017, and the observers are still crunching the data from that first try.

    Even though the collaborators haven’t yet seen the images from that initial look, they geared up to try again, with the expectation of better results. This April and into the future, they hope to achieve the best “seeing” possible for the collection of EHT telescopes and arrays, thanks to their newly developed tools for selecting dates and times of optimal meteorological conditions for the overall observing network.

    “We’re trying to make coherent a network the size of the globe, which is incredible when you think about it,” Doeleman told National Geographic. “It’s a heartbreaker if you [plan for] a night and bad weather closes in” or, conversely, if observations are canceled for a night that the weather is clear, he added.

    “These tools allow us to determine the ideal observing windows for EHT observations and to assess the suitability and impact of new EHT sites,” said Harvard University undergraduate student Rodrigo Córdova Rosado in a recent presentation of this work. Córdova Rosado, a junior who worked on the project with Paine and Doeleman, presented a poster about this research on 9 January at the 231st meeting of the American Astronomical Society in National Harbor, Md.

    A Worldwide Telescope Array

    Although a black hole, by definition, does not emit light, gas and dust surrounding the black hole emit copious light as the incredible gravity of the black hole pulls the material onto itself. The brilliant glow, in turn, silhouettes the black hole, an extraordinarily compressed dot of mass, also known as a singularity.

    Because of the black hole’s ultracompact size, imaging its immediate environment requires an observing technique called very long baseline interferometry (VLBI). VLBI coordinates observations from multiple radio telescopes around the globe to amplify the light from a target and increase the signal-to-noise ratio of an observation. The wider the physical footprint of the array used in VLBI is, the stronger and clearer the radio signal is. Astronomers have used VLBI to view stars coalescing from giant gas clouds, and they plan to use it to glimpse protoplanets forming in circumstellar disks.

    EHT’s nine radio telescopes and arrays at seven observing sites compose the largest VLBI array in the world. Getting onto the observing schedule at any one of the telescopes is very competitive, and negotiating for simultaneous observing time on all nine is even more difficult.

    A Two-Pronged Predictive Approach

    Deciding when to observe requires solving two problems at once, according to Paine. “There’s the strategic problem,” he said, “that is, which week or two weeks are you going to ask for from the observatories.”

    The second is a tactical problem. “Once you’ve got your block of time, and you’re allowed to use a certain number of days within an allocated period, which ones are you going to trigger observations on?” He added, “We’ve been looking at both problems.”

    That’s where NOAA comes in. Córdova Rosado tackled the first problem by gathering global weather data from NOAA’s Global Forecast System (GFS) recorded from 2007 to 2017 at approximately 6-hour intervals. Because EHT observes using radio waves, the researchers were primarily interested in records of relative humidity, ozone mixing ratio, cloud water vapor ratios, and temperature at each of the sites because each of those atmospheric conditions affects the quality of observations. Córdova Rosado ran those data through an atmospheric model that Paine had created to calculate how opaque the atmosphere appears at EHT’s observing frequency of 221 GHz, or a wavelength of 1.4 millimeters.

    3
    A map of worldwide relative humidity data on 2 February 2012 from NOAA’s Global Forecast System. The color gradient shows areas of low (blue) and high (red) relative humidity between 0 and 30 millibars above ground-level pressure—essentially the relative humidity at the surface for GFS data. Researchers with the Event Horizon Telescope collaboration extracted data from maps such as this, generated for many atmospheric layers, to determine the humidity along an observing direction. Credit: Córdova Rosado et al., 2018; data from NOAA/National Centers for Environmental Information

    According to Vincent Fish, a research scientist at the Massachusetts Institute of Technology (MIT) Haystack Observatory in Westford, Mass., coordinated, ground-based radio observations of the galactic center thrive at 221 GHz. “At longer observing wavelengths,” he explained in an MIT press release, “the source would be blurred by free electrons…and we wouldn’t have enough resolution to see the predicted black hole shadow. At shorter wavelengths, the Earth’s atmosphere absorbs most of the signal.” Fish was not involved in this research.

    EHT Sites Prefer It Dry

    Córdova Rosado statistically combined each of the yearly opacity trends to calculate for each day of the year the probability that Sgr A* would have favorable observing conditions simultaneously at all seven sites. The team found that the second and third weeks of April were the best times of year for EHT to observe Sgr A*. The middle of February was a good backup observing window for both the Milky Way’s center and another black hole target. The Northern Hemisphere late spring and summer ranked lowest among possible observing months because of seasonal weather variability.

    4
    The median opacity towards Sgr A* for a typical year at five EHT observing sites (solid lines) and variability ranges (shaded regions), calculated at weekly intervals by the atmospheric model developed by Paine and Córdova Rosado. Opacity values near 1 indicate poor observing conditions, and values near zero indicate good “seeing.” Sites shown here are the Atacama Large Millimeter/Submillimeter Array ( ALMA; red), the Large Millimeter Telescope (LMT; black), the Submillimeter Array (SMA; green), the Submillimeter Telescope (SMT; blue), and the South Pole Telescope (SPT; orange). Credit: Rodrigo Córdova Rosado.

    Some sites, like the South Pole Telescope and the Atacama Large Millimeter/ Submillimeter Array (ALMA) in Chile, offer remarkably stable opacities throughout the year because the areas enjoy consistently low humidity. For more variable Northern Hemisphere sites, the winter months provide the most favorable observing conditions.

    Fish commented that “the probability of having really good weather at every site is almost zero.” However, according to Paine, each of the EHT sites may serve a different purpose for each target, either to act as a mission-critical observing location or to enhance the image quality. Which role an observatory plays during a particular observing run depends on the target location and date, he explained. The team may not need perfect conditions at all sites for every observation.

    More Telescopes, More Targets

    Although climate change has undoubtedly affected the 2007–2017 NOAA meteorological data, it hasn’t significantly influenced the EHT calculations, said Paine. Humidity outweighs temperature as the most important factor for getting clear radio observations, he explained. Although the global average humidity rose slightly over the 10 years of GFS data, he noted, it didn’t go up by enough to alter the team’s predictions.

    Paine described the EHT atmospheric model as the first step in creating what he called a “merit function” that he and his colleagues will use to assess the value of conducting observations on a particular day. Continued access to NOAA’s GFS data, he said, will be critical to making the best use of limited observing time.

    “[NOAA’s] resources are not only used for weather and climate tasks, but they’re also getting leveraged for things like astronomy,” he said. “We’re fortunate to have this resource for optimizing very expensive astronomical observations.”

    —Kimberly M. S. Cartier (@AstroKimCartier), News Writing and Production Intern

    Correction, 6 February 2018: An image caption and a researcher’s statement have been updated to more accurately describe the associated data.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 10:32 am on February 26, 2018 Permalink | Reply
    Tags: , , , , , Millimeter/submillimeter astronomy, Powerful Flare from Star Proxima Centauri Detected with ALMA,   

    From ALMA: “Powerful Flare from Star Proxima Centauri Detected with ALMA” 

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

    ALMA

    26 February, 2018

    Meredith MacGregor
    Carnegie Institution for Science
    Phone: +1 202 478 88 46
    Email: mmacgregor@carnegiescience.edu

    Alycia Weinberger
    Carnegie Institution for Science
    Phone: +1 202 478 88 52
    Email: aweinberger@carnegiescience.edu

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

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

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

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

    1
    An artist’s impression of a flare from Proxima Centauri, modeled after the loops of glowing hot gas seen in the largest solar flares. An artist’s impression of the exoplanet Proxima b is shown in the foreground. Proxima b orbits its star 20 times closer than the Earth orbits the Sun. A flare 10 times larger than a major solar flare would blast Proxima b with 4,000 times more radiation than the Earth gets from our Sun’s flares. Credit: Roberto Molar Candanosa / Carnegie Institution for Science, NASA/SDO, NASA/JPL.

    Puts habitability of nearby system into question

    Using data from the Atacama Large Millimeter/submillimeter Array (ALMA), a team of astronomers discovered that a powerful stellar flare erupted from Proxima Centauri last March. This finding, published in The Astrophysical Journal Letters, raises questions about the habitability of our solar system’s nearest exoplanetary neighbor, Proxima b, which orbits Proxima Centauri.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    At its peak, the newly recognized flare was 10 times brighter than our sun’s largest flares, when observed at similar wavelengths. Stellar flares have not been well studied at the millimeter and submillimeter wavelengths detected by ALMA, especially around stars of Proxima Centauri’s type, called M dwarfs, which are the most common in our galaxy.

    “March 24, 2017, was no ordinary day for Proxima Cen,” said Meredith MacGregor, an astronomer at the Carnegie Institution for Science, Department of Terrestrial Magnetism in Washington, D.C., who led the research with fellow Carnegie astronomer Alycia Weinberger. Along with colleagues from the Harvard-Smithsonian Center for Astrophysics’ David Wilner and Adam Kowalski and Steven Cranmer of the University of Colorado Boulder—they discovered the enormous flare when they reanalyzed ALMA observations taken last year.

    The flare increased Proxima Centauri’s brightness by 1,000 times over 10 seconds. This was preceded by a smaller flare; taken together, the whole event lasted fewer than two minutes of the 10 hours that ALMA observed the star between January and March of last year.

    Stellar flares happen when a shift in the star’s magnetic field accelerates electrons to speeds approaching that of light. The accelerated electrons interact with the highly charged plasma that makes up most of the star, causing an eruption that produces emission across the entire electromagnetic spectrum.

    “It’s likely that Proxima b was blasted by high energy radiation during this flare,” MacGregor explained, adding that it was already known that Proxima Centauri experienced regular, although smaller, X-ray flares. “Over the billions of years since Proxima b formed, flares like this one could have evaporated any atmosphere or ocean and sterilized the surface, suggesting that habitability may involve more than just being the right distance from the host star to have liquid water.”

    An earlier paper that also used the same ALMA data interpreted its average brightness, which included the light output of both the star and the flare together, as being caused by multiple disks of dust encircling Proxima Centauri, not unlike our own solar system’s asteroid and Kuiper belts.

    But when MacGregor, Weinberger, and their team looked at the ALMA data as a function of observing time, instead of averaging it all together, they were able to see the transient explosion of radiation emitted from Proxima Centauri for what it truly was.

    “There is now no reason to think that there is a substantial amount of dust around Proxima Cen,” Weinberger said. “Nor is there any information yet that indicates the star has a rich planetary system like ours.”

    2
    The brightness of Proxima Centauri as observed by ALMA over the two minutes of the event on March 24, 2017. The massive stellar flare is shown in red, with the smaller earlier flare in orange, and the enhanced emission surrounding the flare that could mimic a disk in blue. At its peak, the flare increased Proxima Centauri’s brightness by 1,000 times. The shaded area represents uncertainty. Credit: Meredith MacGregor, Carnegie.

    Additional Information

    The research team was composed by Meredith A. MacGregor [1,2], Alycia J. Weinberger [1], David J. Wilner [3], Adam F. Kowalski [4,5], Steven R. Cranmer [4].

    [1] Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington, DC 20015, USA.

    [2] NSF Astronomy and Astrophysics Postdoctoral Fellow
.

    [3] Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA
.

    [4] Department of Astrophysical and Planetary Sciences, University of Colorado Boulder, 2000 Colorado Ave, Boulder, CO 80305, USA

    [5] National Solar Observatory, University of Colorado Boulder, 3665 Discovery Drive, Boulder, CO 80303, USA.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 7:51 am on February 26, 2018 Permalink | Reply
    Tags: , , , , , Millimeter/submillimeter astronomy,   

    From ALMA: “Young planet creates a scene” 

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

    ALMA

    26 February, 2018

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

    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

    1
    Credit: ALMA (ESO/NAOJ/NRAO)/ D. Fedele et al.

    Nestled in the young Ophiuchus star-forming region, 410 light-years from the Sun, a fascinating protoplanetary disc named AS 209 is slowly being carved into shape. This wonderful image was captured using the high-resolution ALMA telescope, revealing a curious pattern of rings and gaps in the dust surrounding a young star.

    Protoplanetary discs are dense, rotating planes of gas and dust that surround newly formed stars; providing the matter that one day becomes orbiting planets, moons, and other minor bodies. At less than one million years old, this system is very young, but already two clear gaps are being sculpted from the disc.

    The outer gap is deep, wide, and largely a dust-free zone, leading astronomers to believe that a giant planet almost the mass of Saturn is orbiting here — around 800 light-minutes from the central star, and more than three times the distance between Neptune and the Sun! As the planet carves out its path, dust piles up at the outer edge of its orbit, creating ever more defined rings in the disc. The thinner, inner dust gap could have been formed by a smaller planet, but astronomers have raised the intriguing possibility that the large and distant circling planet, in fact, created both paths.

    This inferred Saturn-like planet so far from its central star raises fascinating questions about planet formation at the edges of protoplanetary discs on particularly short timescales.

    Science paper:
    ALMA continuum observations of the protoplanetary disk AS 209. Evidence of multiple gaps opened by a single planet★, Astronomy and Astrophysics.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 1:32 pm on February 23, 2018 Permalink | Reply
    Tags: , , , , , , Millimeter/submillimeter astronomy,   

    From ALMA: “Large Magellanic Cloud Contains Surprisingly Complex Organic Molecules” 

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

    ALMA

    30 January, 2018

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

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

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

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

    1
    Astronomers using ALMA have uncovered chemical “fingerprints” of methanol, dimethyl ether, and methyl formate in the Large Magellanic Cloud. The latter two molecules are the largest organic molecules ever conclusively detected outside the Milky Way. The far-infrared image on the left shows the full galaxy. The zoom-in image shows the star-forming region observed by ALMA. It is a combination of mid-infrared data from Spitzer and visible (H-alpha) data from the Blanco 4-meter telescope. Credit: NRAO/AUI/NSF; ALMA (ESO/NAOJ/NRAO); Herschel/ESA; NASA/JPL-Caltech; NOAO

    NASA/Spitzer Infrared Telescope

    NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam at Cerro Tololo, Chile, housing DECam at an altitude of 7200 feet

    ESA/Herschel spacecraft

    The nearby dwarf galaxy known as the Large Magellanic Cloud (LMC) is a chemically primitive place.

    Large Magellanic Cloud. Adrian Pingstone December 2003

    Unlike the Milky Way, this semi-spiral collection of a few tens-of-billions of stars lacks our galaxy’s rich abundance of heavy elements, like carbon, oxygen, and nitrogen. With such a dearth of heavy elements, astronomers predict that the LMC should contain comparatively paltry amounts of complex carbon-based molecules. Previous observations of the LMC seem to support that view.

    New observations with the Atacama Large Millimeter/submillimeter Array (ALMA), however, have uncovered the surprisingly clear chemical “fingerprints” of the complex organic molecules methanol, dimethyl ether, and methyl formate. Though previous observations found hints of methanol in the LMC, the latter two are unprecedented findings and stand as the most complex molecules ever conclusively detected outside of our galaxy.

    Astronomers discovered the molecules’ faint millimeter-wavelength “glow” emanating from two dense star-forming embryos in the LMC, regions known as “hot cores.” These observations may provide insights into the formation of similarly complex organic molecules early in the history of the universe.

    “Even though the Large Magellanic Cloud is one of our nearest galactic companions, we expect it should share some uncanny chemical similarity with distant, young galaxies from the early universe,” said Marta Sewiło, an astronomer with NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author on a paper appearing in the Astrophysical Journal Letters.

    Astronomers refer to this lack of heavy elements as “low metallicity.” It takes several generations of star birth and star death to liberally seed a galaxy with heavy elements, which then get taken up in the next generation of stars and become the building blocks of new planets.

    “Young, primordial galaxies simply didn’t have enough time to become so chemically enriched,” said Sewiło. “Dwarf galaxies like the LMC probably retained this same youthful makeup because of their relatively low masses, which severely throttles back the pace of star formation.”

    “Due to its low metallicity, the LMC offers a window into these early, adolescent galaxies,” noted Remy Indebetouw, an astronomer at the National Radio Astronomy Observatory in Charlottesville, Virginia, and coauthor on the study. “Star-formation studies of this galaxy provide a stepping stone to understand star formation in the early universe.”

    The astronomers focused their study on the N113 Star Formation Region in the LMC, which is one of the galaxy’s most massive and gas-rich regions. Earlier observations of this area with NASA’s Spitzer Space Telescope and ESA’s Herschel Space Observatory revealed a startling concentration of young stellar objects – protostars that have just begun to heat their stellar nurseries, causing them to glow brightly in infrared light. At least a portion of this star formation is due to a domino-like effect, where the formation of massive stars triggers the formation of other stars in the same general vicinity.

    Sewiło and her colleagues used ALMA to study several young stellar objects in this region to better understand their chemistry and dynamics. The ALMA data surprisingly revealed the telltale spectral signatures of dimethyl ether and methyl formate, molecules that have never been detected so far from Earth.

    Complex organic molecules, those with six or more atoms including carbon, are some of the basic building blocks of molecules that are essential to life on Earth and – presumably – elsewhere in the universe. Though methanol is a relatively simple compound compared to other organic molecules, it nonetheless is essential to the formation of more complex organic molecules, like those that ALMA recently observed, among others.

    If these complex molecules can readily form around protostars, it’s likely that they would endure and become part of the protoplanetary disks of young star systems. Such molecules were likely delivered to the primitive Earth by comets and meteorites, helping to jumpstart the development of life on our planet.

    The astronomers speculate that since complex organic molecules can form in chemically primitive environments like the LMC, it’s possible that the chemical framework for life could have emerged relatively early in the history of the universe.
    Additional Information

    This research is presented in a paper titled “’The detection of hot cores and complex organic molecules in the Large Magellanic Cloud,” by M. Sewiło, et al., which appears in The Astrophysical Journal Letters.

    The research team was composed by Marta Sewilo [1], Remy Indebetouw [2, 3], Steven B. Charnley [1], Sarolta Zahorecz [4, 5], Joana M. Oliveira [6], Jacco Th. van Loon [6], Jacob L. Ward [7], C.-H. Rosie Chen [8], Jennifer Wiseman [1], Yasuo Fukui [9], Akiko Kawamura [10], Margaret Meixner [11], Toshikazu Onishi [4], and Peter Schilke [12].

    [1] NASA Postdoctoral Program Fellow, NASA Goddard Space Flight Center, 8800 Greenbelt Rd, Greenbelt, MD 20771, USA
    [2] Department of Astronomy, University of Virginia, PO Box 400325, Charlottesville, VA 22904, USA
    [3] National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville, VA 22903, USA
    [4] Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan
    [5] Chile Observatory, National Astronomical Observatory of Japan, National Institutes of Natural Science, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588, Japan
    [6] Lennard-Jones Laboratories, Keele University, ST5 5BG, UK
    [7] Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg Germany
    [8] Max-Planck-Institut für Radioastronomie, Auf dem Hügel, 69 D-53121 Bonn, Germany
    [9] School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
    [10] National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
    [11] Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
    [12] I. Physikalisches Institut der Universität zu Köln, Zülpicher Str. 77, 50937, Köln, Germany

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
  • richardmitnick 2:19 pm on February 20, 2018 Permalink | Reply
    Tags: , , , , , , Millimeter/submillimeter astronomy,   

    From ALMA: “Chaotic Turbulence Roiling ‘Most Luminous Galaxy’ in the Universe” 2016 

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

    ALMA

    15 January, 2016 [Just found this.]

    Contacts

    Tanio Díaz Santos
    Núcleo de Astronomía, Facultad de Ingeniería
    Universidad Diego Portales, Santiago, Chile
    Tel: +56 2 2213 0480
    Email: tanio.diaz@mail.udp.cl

    Valeria Foncea

    Education and Public Outreach Officer

    Joint ALMA Observatory

    Santiago, Chile

    Tel: +56 2 467 6258

    Cell: +56 9 75871963
    Email: vfoncea@alma.cl

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

    Richard Hook
    Public Information Officer, ESO

    Garching bei München, Germany

    Tel: +49 89 3200 6655

    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    Masaaki Hiramatsu

    Education and Public Outreach Officer, NAOJ Chile
    Observatory
Tokyo, Japan

    Tel: +81 422 34 3630

    E-mail: hiramatsu.masaaki@nao.ac.jp

    1
    Artist impression of W2246-0526, a single galaxy glowing in infrared light as intensely as approximately 350 trillion suns. It is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with ALMA. Credit: NRAO/AUI/NSF; Dana Berry / SkyWorks; ALMA (ESO/NAOJ/NRAO).

    The most luminous galaxy in the Universe –a so-called obscured quasar 12.4 billion light-years away – is so violently turbulent that it may eventually jettison its entire supply of star-forming gas, according to new observations with the Atacama Large Millimeter/submillimeter Array (ALMA).

    A team of researchers used ALMA to trace, for the first time, the actual motion of the galaxy’s interstellar medium – the gas and dust between the stars. What they found, according to Tanio Díaz-Santos of the Universidad Diego Portales in Santiago, Chile, and lead author of this study, is a galaxy “so chaotic that it is ripping itself apart.”

    Previous studies with NASA’s Wide-field Infrared Survey Explorer (WISE) spacecraft reveal that the galaxy, dubbed W2246-0526, is glowing in infrared light as intensely as approximately 350 trillion suns.

    NASA/WISE Telescope

    Evidence strongly suggests that this galaxy is actually an obscured quasar, a very distant galaxy which contains a voraciously feeding supermassive black hole at its center that is completely obscured behind a thick blanket of dust.

    This galaxy’s startling brightness is powered by a tiny, yet incredibly energetic disk of gas that is being superheated as it spirals in on the supermassive black hole. The light from this blazingly bright accretion disk is then absorbed by the surrounding dust, which re-emits the energy as infrared light.

    “These properties make this object a beast in the infrared,” said Roberto Assef, an astronomer with the Universidad Diego Portales and leader of the ALMA observing team. “The powerful infrared energy emitted by the dust then has a direct and violent impact on the entire galaxy, producing extreme turbulence throughout the interstellar medium.”

    The astronomers compare this turbulent action to a pot of boiling water. If these conditions continue, they say, the galaxy’s intense infrared radiation would boil away all of its interstellar gas.

    This galaxy belongs to a very unusual type of quasar known as Hot, Dust-Obscured Galaxies or Hot DOGs. These objects are very rare; only 1 out of every 3,000 quasars observed by WISE belong to this class.

    The research team used ALMA to precisely map the motion of ionized carbon atoms throughout the entire galaxy. These atoms, which are tracers for interstellar gas, naturally emit infrared light, which becomes shifted to millimeter wavelengths as it travels the vast cosmic distances to Earth due to the expansion of the Universe.

    “Large amounts of ionized carbon were found in an extremely turbulent dynamic state throughout the galaxy,” Díaz-Santos describes. The data reveal that this interstellar material is careening anywhere from 500 to 600 kilometers per second across the entire galaxy.

    The astronomers believe that this turbulence is primarily due to the fact that the region around the black hole is at least 100 times more luminous than the rest of the host galaxy combined; in other quasars, the proportion is much more modest. This intense yet localized radiation exerts tremendous pressure on the entire galaxy, to potentially devastating effect.

    “We suspected that this galaxy was in a transformative stage of its life because of the enormous amount of infrared energy discovered with WISE,” said Peter Eisenhardt with NASA’s Jet Propulsion Laboratory in Pasadena, California, and scientific leader of the WISE mission. “Now ALMA has shown us that the raging furnace in this galaxy is making the pot boil over.”

    Current models of galactic dynamics combined with the ALMA data indicate that this galaxy is unstable and its interstellar gas is being blown away in all directions. This means that the galaxy’s Hot DOG days are numbered as it matures into a more traditional unobscured quasar.

    “If this pattern continues, it is possible that in the future W2246 ends up shedding a large part of the gas and dust it contains,” concludes Manuel Aravena also from the Universidad Diego Portales, and co-author of the study. “Only ALMA, with its unparalleled resolution, can allow us to see this object in high definition and fathom such an important episode in the life of this galaxy.”

    This article, The Strikingly Uniform, Highly Turbulent Interstellar Medium of The Most Luminous Galaxy in the Universe, will be published in The Astrophysical Journal Letters.

    See the full article here .

    Please help promote STEM in your local schools.
    STEM Icon
    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.

    NRAO Small
    ESO 50 Large
    NAOJ

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel