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  • richardmitnick 12:13 pm on May 19, 2019 Permalink | Reply
    Tags: "CosmoGAN Neural Network to Study Dark Matter", , , , Cosmology, , , , New deep learning network,   

    From insideHPC: “CosmoGAN Neural Network to Study Dark Matter” 

    From insideHPC

    May 18, 2019
    Rich Brueckner

    As cosmologists and astrophysicists delve deeper into the darkest recesses of the universe, their need for increasingly powerful observational and computational tools has expanded exponentially. From facilities such as the Dark Energy Spectroscopic Instrument to supercomputers like Lawrence Berkeley National Laboratory’s Cori system at NERSC, they are on a quest to collect, simulate, and analyze increasing amounts of data that can help explain the nature of things we can’t see, as well as those we can.

    Why opt for GANs instead of other types of generative models? Performance and precision, according to Mustafa.

    “From a deep learning perspective, there are other ways to learn how to generate convergence maps from images, but when we started this project GANs seemed to produce very high-resolution images compared to competing methods, while still being computationally and neural network size efficient,” he said.

    “We were looking for two things: to be accurate and to be fast,” added co-author Zaria Lukic, a research scientist in the Computational Cosmology Center at Berkeley Lab. “GANs offer hope of being nearly as accurate compared to full physics simulations.”

    The research team is particularly interested in constructing a surrogate model that would reduce the computational cost of running these simulations. In the Computational Astrophysics and Cosmology paper, they outline a number of advantages of GANs in the study of large physics simulations.

    “GANs are known to be very unstable during training, especially when you reach the very end of the training and the images start to look nice – that’s when the updates to the network can be really chaotic,” Mustafa said. “But because we have the summary statistics that we use in cosmology, we were able to evaluate the GANs at every step of the training, which helped us determine the generator we thought was the best. This procedure is not usually used in training GANs.”

    Using the CosmoGAN generator network, the team has been able to produce convergence maps that are described by – with high statistical confidence – the same summary statistics as the fully simulated maps. This very high level of agreement between convergence maps that are statistically indistinguishable from maps produced by physics-based generative models offers an important step toward building emulators out of deep neural networks.

    1
    Weak lensing convergence maps for the ΛCDM cosmological model. Randomly selected maps from validation dataset (top) and GAN-generated examples (bottom).

    Weak gravitational lensing NASA/ESA Hubble

    Lambda-Cold Dark Matter, Accelerated Expansion of the Universe, Big Bang-Inflation (timeline of the universe) Date 2010 Credit: Alex Mittelmann Cold creation


    NERSC Cray Cori II supercomputer at NERSC at LBNL, named after Gerty Cori, the first American woman to win a Nobel Prize in science

    LBNL/DESI spectroscopic instrument on the Mayall 4-meter telescope at Kitt Peak National Observatory starting in 2018

    NOAO/Mayall 4 m telescope at Kitt Peak, Arizona, USA, Altitude 2,120 m (6,960 ft)

    Toward this end, gravitational lensing is one of the most promising tools scientists have to extract this information by giving them the ability to probe both the geometry of the universe and the growth of cosmic structure.

    Gravitational Lensing NASA/ESA

    Gravitational lensing distorts images of distant galaxies in a way that is determined by the amount of matter in the line of sight in a certain direction, and it provides a way of looking at a two-dimensional map of dark matter, according to Deborah Bard, Group Lead for the Data Science Engagement Group at NERSC.

    “Gravitational lensing is one of the best ways we have to study dark matter, which is important because it tells us a lot about the structure of the universe,” she said. “The majority of matter in the universe is dark matter, which we can’t see directly, so we have to use indirect methods to study how it is distributed.”

    But as experimental and theoretical datasets grow, along with the simulations needed to image and analyze this data, a new challenge has emerged: these simulations are increasingly – even prohibitively – computationally expensive. So computational cosmologists often resort to computationally cheaper surrogate models, which emulate expensive simulations. More recently, however, “advances in deep generative models based on neural networks opened the possibility of constructing more robust and less hand-engineered surrogate models for many types of simulators, including those in cosmology,” said Mustafa Mustafa, a machine learning engineer at NERSC and lead author on a new study that describes one such approach developed by a collaboration involving Berkeley Lab, Google Research, and the University of KwaZulu-Natal.

    A variety of deep generative models are being investigated for science applications, but the Berkeley Lab-led team is taking a unique tack: generative adversarial networks (GANs). In a paper published May 6, 2019 in Computational Astrophysics and Cosmology, they discuss their new deep learning network, dubbed CosmoGAN, and its ability to create high-fidelity, weak gravitational lensing convergence maps.

    “A convergence map is effectively a 2D map of the gravitational lensing that we see in the sky along the line of sight,” said Bard, a co-author on the Computational Astrophysics and Cosmology paper. “If you have a peak in a convergence map that corresponds to a peak in a large amount of matter along the line of sight, that means there is a huge amount of dark matter in that direction.”

    The Advantages of GANs

    “The huge advantage here was that the problem we were tackling was a physics problem that had associated metrics,” Bard said. “But with our approach, there are actual metrics that allow you to quantify how accurate your GAN is. To me that is what is really exciting about this – how these kinds of physics problems can influence machine learning methods.”

    Ultimately such approaches could transform science that currently relies on detailed physics simulations that require billions of compute hours and occupy petabytes of disk space – but there is considerable work still to be done. Cosmology data (and scientific data in general) can require very high-resolution measurements, such as full-sky telescope images.

    “The 2D images considered for this project are valuable, but the actual physics simulations are 3D and can be time-varying ?and irregular, producing a rich, web-like structure of features,” said Wahid Bhmiji, a big data architect in the Data and Analytics Services group at NERSC and a co-author on the Computational Astrophysics and Cosmology paper. “In addition, the approach needs to be extended to explore new virtual universes rather than ones that have already been simulated – ultimately building a controllable CosmoGAN.”

    “The idea of doing controllable GANs is essentially the Holy Grail of the whole problem that we are working on: to be able to truly emulate the physical simulators we need to build surrogate models based on controllable GANs,” Mustafa added. “Right now we are trying to understand how to stabilize the training dynamics, given all the advances in the field that have happened in the last couple of years. Stabilizing the training is extremely important to actually be able to do what we want to do next.”

    See the full article here .

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    Founded on December 28, 2006, insideHPC is a blog that distills news and events in the world of HPC and presents them in bite-sized nuggets of helpfulness as a resource for supercomputing professionals. As one reader said, we’re sifting through all the news so you don’t have to!

    If you would like to contact me with suggestions, comments, corrections, errors or new company announcements, please send me an email at rich@insidehpc.com. Or you can send me mail at:

    insideHPC
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  • richardmitnick 9:41 am on May 19, 2019 Permalink | Reply
    Tags: "Mission control 'saves science'", , , , Cosmology, , ESA’s Earth Explorer Swarm satellites   

    From European Space Agency: “Mission control ‘saves science'” 

    ESA Space For Europe Banner

    From European Space Agency

    1
    Earth observation missions

    17 May 2019

    Every minute, ESA’s Earth observation satellites gather dozens of gigabytes of data about our planet – enough information to fill the pages on a 100-metre long bookshelf. Flying in low-Earth orbits, these spacecraft are continuously taking the pulse of our planet, but it’s teams on the ground at ESA’s Operations Centre in Darmstadt, Germany, that keep our explorers afloat.

    3
    ESOC Main Control Room in Darmstadt, Germany

    From flying groups of spacecraft in complex formations to dodging space debris and navigating the ever-changing conditions in space known as space weather, ESA’s spacecraft operators ensure we continue to receive beautiful images and vital data on our changing planet.

    Get in formation

    Many Earth observation satellites travel in formation. For example, the Copernicus Sentinel-5P satellite follows behind the Suomi-NPP satellite (from the National Oceanic and Atmospheric Administration). Flying in a loose trailing formation, they observe parts of our planet in quick succession and monitor rapidly evolving situations. Together they can also cross-validate instruments on board as well as the data acquired.

    ESA Copernicus Sentinel-5P

    NOAA Suomi-NPP satellite via NASA Goddard

    ESA’s Earth Explorer Swarm satellites are another example of complex formation flying.

    ESA/Swarm

    On a mission to provide the best ever survey of Earth’s geomagnetic field, they are made up of three identical satellites flying in what is called a constellation formation.

    Swarm’s individual satellites operate together under shared control in a synchronised manner, accomplishing the same objective of one giant – and more expensive – satellite.

    “Formation flying has all the challenges of flying many single spacecraft, except with the added complexity that we need to maintain a regular distance between all of these high-speed and high-tech eyes on Earth,” explains Jose Morales Santiago, ESA’s Head of the Earth Observation Mission Operations Division.

    “Every decision we make, every command we send, has to be the right one for each spacecraft – particularly when it comes to manoeuvres. These must be planned properly so that they do not endanger companion satellites, while keeping a consistent configuration across the formation.”

    Saving Science

    Last year, ESA’s Earth observation missions performed a total of 28 ‘collision avoidance manoeuvres’. These manoeuvres saw operators send the orders to a spacecraft to get out of the way of an oncoming piece of space debris.

    An impact with a fast-moving piece of space junk has the potential to destroy an entire satellite and in the process create even more debris. As a spacecraft ‘swerves’ to avoid collision, science instruments may need to be turned off to ensure their safety and avoid being contaminated by the thrusting engine.

    Teams at mission control consider how to keep Europe’s fleet of Earth observers safe while maximising the vital work they are able to do. Recently, they came up with an ingenious concept to ‘save science’ during such manoeuvres of the Sentinel-5P satellite.

    The Sentinel team quickly realised that during a collision avoidance manoeuvre they would have to suspend science collection for almost a day, because of the emergency firing of the thrusters.

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    Sentinel control room at ESA’s operation centre in Darmstadt, Germany.

    “That’s a lot of data to miss out on. As the amount of space debris is currently increasing, this would be something we would need to do more and more often,” explains Pierre Choukroun, Sentinel-5P Spacecraft Operations Engineer, who came up with the fix.

    “So we designed and validated a new on-board function to enhance the spacecraft’s autonomy, such that the science data loss is reduced to a bare minimum. We are very much looking forward to securing more data for the science community in the near future!”

    With this new strategy, the science instruments on Sentinel-5P would be shut off for around on hour compared with an entire day!

    Sun protection

    As if dodging bits of space debris weren’t enough for Europe’s Earth explorers, they also have to navigate the turbulent weather conditions in space.

    Space weather refers to the environmental conditions around Earth due to the dynamic nature of our Sun. The constant mood swings of our star influence the functioning and reliability of our satellites in space, as well as infrastructure on the ground.

    When the Sun is particularly active, it adds extra energy to Earth’s atmosphere, changing the density of the air at low-Earth orbits. Increased energy in the atmosphere means that satellites in this region experience more ‘drag’ – a force that acts in the opposite direction to the motion of the spacecraft, causing it to decrease in altitude.

    Operators need this information to know when to perform manoeuvres to “boost” the satellite’s speed in order to counter drag and keep it in its proper orbit.

    5
    Space Weather Phenomena

    This drag effect also changes the speed and position of space debris around Earth, meaning our understanding of the debris environment needs to be constantly updated in light of changing space weather.

    “While Earth observation satellites monitor the weather on Earth, we have to stay aware of the changing weather in space,” says Thomas Ormston, Spacecraft Operations Engineer at ESA.

    “This is vital because understanding atmospheric drag is fundamental to predicting when we will be threatened by space debris and determining when and how big our spacecraft manoeuvres need to be to keep delivering great science to our users.”

    Space weather also impacts communication between ground stations and satellites due to changes in the upper atmosphere, the ionosphere, during solar events. Because of this, satellite operators avoid critical satellite operations like manoeuvres or updates of the on board software during periods of high solar activity.

    Find out more about Earth observation at ESA here, and catch up on all the latest information from this year’s Living Planet Symposium at http://www.esa.int/livingplanet.

    See the full article here .


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    Please help promote STEM in your local schools.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

    ESA50 Logo large

     
  • richardmitnick 12:53 pm on May 17, 2019 Permalink | Reply
    Tags: "Long March-3C lofts Beidou-2G8 (GEO-8)", , , , BeiDou-3 satellite, Cosmology   

    From NASA Spaceflight: “Long March-3C lofts Beidou-2G8 (GEO-8)” 

    NASA Spaceflight

    From NASA Spaceflight

    May 17, 2019
    Rui C. Barbosa

    1
    A new navigation satellite was successfully launched by China on Friday. The launch of Beidou-2G8 (GEO-8) took place from the LC2 Launch Complex of the Xichang Satellite Launch Center, Sichuan province, using the Long March-3C/G2 (Y16) launch vehicle. Launch time was 15:48 UTC.

    Also designated Beidou-45, the satellite is part of the GEO component of the 2nd phase of the Chinese Beidou (Compass) satellite navigation system, using both geostationary satellites and satellites in intermediate orbits.
    The satellites are based on the DFH-3B Bus. This bus has a payload increased to 450 kg and payload power to 4,000 W.

    The spacecraft feature a phased array antenna for navigation signals and a laser retroreflector and additionally deployable S/L-band and C-band antennas. With a launch mass of 4,600 kg, spacecraft dimensions are noted to be 2.25 by 1.0 by 1.22 meters.

    Previous Beidou satellites were orbited on November 18, 2018, with a Long March-3B/YZ-1 launch vehicle launching the Beidou-3M17 (Beidou-42) and Beidou-3M18 (Beidou-43) satellites, and on April 20, 2019, with a Long March-3B/G2 orbiting the Beidou-3IGSO-1 (Beidou-44). Both launches took place from Xichang. The previous Beidou-2G satellite, Beidou-2G7 (Beidou-23), was launch on June 12, 2016.

    The Beidou Navigation Satellite System (BDS) has been independently constructed, developed and operated by China taking into account the needs of the country’s national security, economic and social development. As a space infrastructure of national significance, BDS provides all-time, all-weather and high-accuracy positioning, navigation and timing services to global users.

    2
    Render of a BeiDou-3 satellite by J. Huart.

    A new navigation satellite was successfully launched by China on Friday. The launch of Beidou-2G8 (GEO-8) took place from the LC2 Launch Complex of the Xichang Satellite Launch Center, Sichuan province, using the Long March-3C/G2 (Y16) launch vehicle. Launch time was 15:48 UTC.

    Also designated Beidou-45, the satellite is part of the GEO component of the 2nd phase of the Chinese Beidou (Compass) satellite navigation system, using both geostationary satellites and satellites in intermediate orbits.
    The satellites are based on the DFH-3B Bus. This bus has a payload increased to 450 kg and payload power to 4,000 W.

    The spacecraft feature a phased array antenna for navigation signals and a laser retroreflector and additionally deployable S/L-band and C-band antennas. With a launch mass of 4,600 kg, spacecraft dimensions are noted to be 2.25 by 1.0 by 1.22 meters.

    Previous Beidou satellites were orbited on November 18, 2018, with a Long March-3B/YZ-1 launch vehicle launching the Beidou-3M17 (Beidou-42) and Beidou-3M18 (Beidou-43) satellites, and on April 20, 2019, with a Long March-3B/G2 orbiting the Beidou-3IGSO-1 (Beidou-44). Both launches took place from Xichang. The previous Beidou-2G satellite, Beidou-2G7 (Beidou-23), was launch on June 12, 2016.

    The Beidou Navigation Satellite System (BDS) has been independently constructed, developed and operated by China taking into account the needs of the country’s national security, economic and social development. As a space infrastructure of national significance, BDS provides all-time, all-weather and high-accuracy positioning, navigation and timing services to global users.

    Along with the development of the BDS service capability, related products have been widely applied in communication, marine fishery, hydrological monitoring, weather forecasting, surveying, mapping and geographic information, forest fire prevention, time synchronization for communication systems, power dispatching, disaster mitigation and relief, emergency search and rescue, and other fields.

    Navigation satellite systems are public resources shared by the whole globe, and multi-system compatibility and interoperability have become a trend. China applies the principle that “BDS is developed by China, and dedicated to the world”, serving the development of the Silk Road Economic Belt, and actively pushing forward international cooperation related to BDS.

    As BDS joins hands with other navigation satellite systems, China will work with all other countries, regions and international organizations to promote global satellite navigation development and make BDS further serve the world and benefit mankind.

    China started to explore a path to develop a navigation satellite system suitable for its national conditions, and gradually formulated a three-step development strategy: completing the construction of BDS-1 and provide services to the whole country by the end of 2000; completing the construction of BDS-2 and provide services to the Asia-Pacific region by the end of 2012; and to complete the construction of BDS-3 and provide services worldwide around 2020 with a constellation of 27 MEOs plus 5 GEOs and the existing 3 IGSOs satellites of the regional system. CNSS would provide global navigation services, similarly to the GPS, GLONASS or Galileo systems.

    The Beidou Phase III system includes the migration of its civil Beidou 1 or B1 signal from 1561.098 MHz to a frequency centered at 1575.42 MHz – the same as the GPS L1 and Galileo E1 civil signals – and its transformation from a quadrature phase shift keying (QPSK) modulation to a multiplexed binary offset carrier (MBOC) modulation similar to the future GPS L1C and Galileo’s E1.

    The Phase II B1 open service signal uses QPSK modulation with 4.092 megahertz bandwidth centered at 1561.098 MHz.

    The current Beidou constellation spacecraft are transmitting open and authorized signals at B2 (1207.14 MHz) and an authorized service at B3 (1268.52 MHz).

    Real-time, stand-alone Beidou horizontal positioning accuracy was classed as better than 6 meters (95 percent) and with a vertical accuracy better than 10 meters (95 percent).

    The development of the CZ-3C started in February 1999. The rocket has a liftoff mass of 345,000 kg, sporting structure functions to withstand the various internal and external loads on the launch vehicle during transportation, hoisting and flight.

    The rocket structure also combines all sub-systems together and is composed of two strap-on boosters, a first stage, a second stage, a third stage and payload fairing.

    The first two stages, as well as the two strap-on boosters, use hypergolic (N2O4/UDMH) fuel while the third stage uses cryogenic (LOX/LH2) fuel. The total length of the CZ-3C is 54.838 meters, with a diameter of 3.35 meters on the core stage and 3.00 meters on the third stage.

    On the first stage, the CZ-3C uses a DaFY6-2 engine with a 2961.6 kN thrust and a specific impulse of 2556.2 Ns/kg. The first stage diameter is 3.35 m and the stage length is 26.972 m.

    Each strap-on booster is equipped with a DaFY5-1 engine with a 704.4 kN thrust and a specific impulse of 2556.2 Ns/kg. The strap-on booster diameter is 2.25 m and the strap-on booster length is 15.326 m.

    The second stage is equipped with a DaFY20-1 main engine (742 kN / 2922.57 Ns/kg) and four DaFY21-1 vernier engines (11.8 kN / 2910.5 Ns/kg each). The second stage diameter is 3.35 m and the stage length is 9.470 m.

    The third stage is equipped with two YF-75 engines developing 78.5 kN each and with a specific impulse of 4312 Ns/kg. The fairing diameter of the CZ-3C is 4.00 meters and has a length of 9.56 meters.

    The Xichang Satellite Launch Centre is situated in the Sichuan Province, south-western China and is the country’s launch site for geosynchronous orbital launches.

    Equipped with two launch pads (LC2 and LC3), the center has a dedicated railway and highway lead directly to the launch site.

    6

    The Command and Control Centre is located seven kilometers south-west of the launch pad, providing flight and safety control during launch rehearsal and launch.

    Other facilities on the Xichang Satellite Launch Centre are the Launch Control Centre, propellant fuelling systems, communications systems for launch command, telephone and data communications for users, and support equipment for meteorological monitoring and forecasting.

    The first launch from Xichang took place at 12:25UTC on January 29, 1984, when the Chang Zheng-3 (Y-1) was launched the Shiyan Weixing (14670 1984-008A) communications satellite into orbit.

    What’s next for China in 2019?

    Two days after the launch of Beidou-45, a Long March-4C launch vehicle will orbit the Yaogan Weixing-33 mission from the Taiyuan Satellite Launch Center. This will probably be a SAR military mission similar to previous ones launched from Taiyuan. Launch is scheduled for May 22.

    In late May we may assist to the launch of the first fist of the private Jielong-1 carrying four satellites and on the first days of June the first launch of the private Shuang Quxian-1 carrying seven satellites. Both launches will take place from the Jiuquan Satellites Launch Center that will also be the launch site for the launch of the next generation recoverable satellite – Shijian-19 – at the end of June. The launch will be made using a Long March-2D launch vehicle.

    See the full article here .

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    Please help promote STEM in your local schools.

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    NASA Spaceflight , now in its eighth year of operations, is already the leading online news resource for everyone interested in space flight specific news, supplying our readership with the latest news, around the clock, with editors covering all the leading space faring nations.

    Breaking more exclusive space flight related news stories than any other site in its field, NASASpaceFlight.com is dedicated to expanding the public’s awareness and respect for the space flight industry, which in turn is reflected in the many thousands of space industry visitors to the site, ranging from NASA to Lockheed Martin, Boeing, United Space Alliance and commercial space flight arena.

    With a monthly readership of 500,000 visitors and growing, the site’s expansion has already seen articles being referenced and linked by major news networks such as MSNBC, CBS, The New York Times, Popular Science, but to name a few.

     
  • richardmitnick 12:14 pm on May 17, 2019 Permalink | Reply
    Tags: , , , , Cosmology,   

    From AAS NOVA: “Focus on SOFIA: HAWC+” 

    AASNOVA

    From AAS NOVA

    17 May 2019
    Susanna Kohler

    1
    This composite, false-color image shows the starburst galaxy Messier 82 as seen by Kitt Peak Observatory, the Spitzer Space Telescope, and SOFIA. The magnetic field detected by SOFIA, shown as streamlines, appears to be dragged along by the winds flowing from the poles of this galaxy. [NASA/SOFIA/E. Lopez-Rodriguez/Spitzer/J. Moustakas et al.]

    Kitt Peak National Observatory of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O’odham Nation, 88 kilometers 55 mi west-southwest of Tucson, Arizona, Altitude 2,096 m (6,877 ft)

    NASA/Spitzer Infrared Telescope

    In December, AAS Nova Editor Susanna Kohler had the opportunity to fly aboard the NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA). This week we’re taking a look at that flight, as well as some of the recent science the observatory produced and published in an ApJ Letters Focus Issue.

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    The HAWC+ instrument mounted on the SOFIA telescope. [NASA]

    Meet HAWC+

    HAWC+ is a one-of-a-kind instrument: it’s the only currently operating astronomical camera that takes images in far-infrared light. HAWC+ observes in the 50-μm to 240-μm range at high angular resolution, affording us a detailed look at low-temperature phenomena, like the early stages of star and planet formation.

    In addition to the camera, HAWC+ also includes a polarimeter, which allows the instrument to measure the alignment of incoming light waves produced by dust emission. By observing this far-infrared polarization, HAWC+ can produce detailed maps of otherwise invisible celestial magnetic fields. The insight gained with HAWC+ spans an incredible range of astronomical sources, from nearby star-forming regions to the large-scale environments surrounding other galaxies.

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    Artist’s conception of Cygnus A, surrounded by the torus of dust and debris with jets launching from its center. Magnetic fields are illustrated trapping dust near the supermassive black hole at the galaxy’s core. [NASA/SOFIA/Lynette Cook]

    Some Recent HAWC+ Science

    Cygnus A is the closest and most powerful radio-loud active galactic nucleus. At its heart, a supermassive black hole is actively accreting material, producing enormous jets — but this core is difficult to learn about, because it is heavily shrouded by dust.

    In a recent study led by Enrique Lopez-Rodriguez (SOFIA Science Center; National Astronomical Observatory of Japan), a team of scientists has used HAWC+ to observe the polarized infrared emission from aligned dust grains in the dusty torus surrounding Cygnus A’s core. Lopez-Rodriguez and collaborators find that a coherent dusty and magnetic field structure dominates the infrared emission around the nucleus, suggesting that magnetic fields confine the torus and funnel the dust in to accrete onto the supermassive black hole.

    Messier 82 and NGC 253 are two nearby starburst galaxies — galaxies with a high rate of star formation. Such galaxies often have strong outflowing galactic winds, which are thought to contribute to the enrichment of the intergalactic medium with both heavy elements and magnetic fields.

    A study led by Terry Jay Jones (University of Minnesota) uses HAWC+ to map out the magnetic field geometry in the disk and central regions of these two galaxies. M82 shows the most spectacular results, revealing clear evidence for a massive polar outflow that drags the magnetic field vertically away from the disk along with entrained gas and dust.

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    SOFIA/HAWC+ 89 μm detection of the gravitationally lensed starburst galaxy J1429-0028. Right: false-color composite image of J1429-0028 from Hubble and Keck. [Ma et al. 2018]

    A study led by Jingzhe Ma (University of California, Irvine) presents the HAWC+ detection of the distant, gravitationally lensed starburst galaxy HATLAS J1429-0028. This beautiful system consists of an edge-on foreground disk galaxy and a nearly complete Einstein ring of an ultraluminous infrared background galaxy. What causes this background galaxy to shine so brightly in infrared wavelengths? The HAWC+ observations suggest it’s not due to emission from an active galactic nucleus; instead, this galaxy is likely powered purely by star formation.

    5
    The G 9 region, as represented by the Digital Palomar Observatory Sky Survey. The cyan polygon represents the SOFIA HAWC+ coverage of the filamentary dark cloud GF 9. The yellow diamond marks the YSO GF 9-2. [Clemens et al. 2018]

    In a recent study examining the geometry of magnetic fields surrounding sites of massive star formation, Dan Clemens (Boston University) and collaborators obtained HAWC+ observations of a young stellar object (YSO) embedded in a molecular cloud. The polarimetric measurements of HAWC+ revealed the magnetic field configuration around the YSO, the dense core that hosts it, and the clumpy filamentary dark cloud that surrounds it, GF 9.

    Surprisingly, the observations show a remarkably uniform magnetic field threading the entire region, from the outer, diffuse cloud edge all the way down to the smallest scales of the YSO surroundings. These results contradict some models of how cores and YSOs form, providing important information that will help us better understand this process.

    Citation

    ApJL Focus issue:
    Focus on New Results from SOFIA

    HAWC+ articles:
    “The Highly Polarized Dusty Emission Core of Cygnus A,” Enrique Lopez-Rodriguez et al. 2018 ApJL 861 L23. doi:10.3847/2041-8213/aacff5
    “SOFIA Far-infrared Imaging Polarimetry of M82 and NGC 253: Exploring the Supergalactic Wind,” Terry Jay Jones et al. 2019 ApJL 870 L9. doi:10.3847/2041-8213/aaf8b9
    “SOFIA/HAWC+ Detection of a Gravitationally Lensed Starburst Galaxy at z = 1.03,” Jingzhe Ma et al. 2018 ApJ 864 60. doi:10.3847/1538-4357/aad4a0
    “Magnetic Field Uniformity Across the GF 9-2 YSO, L1082C Dense Core, and GF 9 Filamentary Dark Cloud,” Dan P. Clemens et al. 2018 ApJ 867 79. doi:10.3847/1538-4357/aae2af

    Related Journal Articles

    Polarized Mid-infrared Synchrotron Emission in the Core of Cygnus A doi: 10.1088/0004-637X/793/2/81
    The Emission and Distribution of Dust of the Torus of NGC 1068 doi: 10.3847/1538-4357/aabd7b
    Subaru Spectroscopy and Spectral Modeling of Cygnus A doi: 10.1088/0004-637X/788/1/6
    SOFIA/HAWC+ Detection of a Gravitationally Lensed Starburst Galaxy at z = 1.03 doi: 10.3847/1538-4357/aad4a0
    The Spitzer View of FR I Radio Galaxies: On the Origin of the Nuclear Mid-Infrared Continuum doi: 10.1088/0004-637X/701/2/891
    Mid-infrared Spectroscopy of High-redshift 3CRR Sources doi: 10.1088/0004-637X/717/2/766

    See the full article here .


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    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 12:40 pm on May 16, 2019 Permalink | Reply
    Tags: "Focus on SOFIA: EXES", , , , , Cosmology,   

    From AAS NOVA: “Focus on SOFIA: EXES” 

    AASNOVA

    From AAS NOVA

    6 May 2019
    Susanna Kohler

    1
    This false-color infrared image, captured by NASA’s WISE telescope, reveals young, massive stars (pink objects near center) forming in the Rho Ophiuchi cloud complex. SOFIA’s EXES spectrograph is well suited for studying the chemistry of massive star formation. [NASA/JPL-Caltech/WISE Team]

    In December, AAS Nova Editor Susanna Kohler had the opportunity to fly aboard the NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA). This week we’re taking a look at that flight, as well as some of the recent science the observatory produced and published in an ApJ Letters Focus Issue.

    One of SOFIA’s great strengths is that the instruments mounted on this flying telescope can be easily swapped out, allowing for a broad range of infrared observations. Three of SOFIA’s instruments are featured in science recently published in the ApJ Letters Focus Issue: the Far Infrared Field-Imaging Line Spectrometer (FIFI-LS), the High-Resolution Airborne Wideband Camera Plus (HAWC+), and the Echelon-Cross-Echelle Spectrograph (EXES).

    2
    The EXES instrument mounted on the SOFIA telescope. [NASA/SOFIA/EXES/Matthew Richter]

    Meet EXES

    EXES is used for high-resolution spectroscopy at mid-infrared wavelengths — from 4.5 to 28.3 µm — to study molecular gas in dense, quiescent clouds and protostellar disks. EXES uses a special coarsely-ruled aluminum reflection grating to spread light into a spectrum, allowing scientists to identify specific spectral lines associated with emission from different molecules.

    The instrument’s high spectral resolution enables the study of molecular hydrogen, water vapor, and methane from sources like molecular clouds, protoplanetary disks, interstellar shocks, circumstellar shells, and planetary atmospheres. For many sources, EXES is able to achieve comparable sensitivity even to space-based observatories like Spitzer.

    NASA/Spitzer Infrared Telescope

    3
    Image from the Subaru telescope showing the location of the Becklin-Neugebauer object in Orion. [NAOJ/Subaru Telescope]


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

    Some Recent EXES Science

    A young, massive star dubbed the Becklin-Neugebauer object is irrationally speeding through the Orion nebular cluster at a relative speed of ~30 km/s! One proposed explanation for this object’s unusual velocity is that it was caught in a three-body dynamical interaction inside a nebula, during which it was violently ejected.

    If true, we could expect that the Becklin-Neugebauer object might have dragged some of the hot, dense molecular gas along with it when it was ejected. A team of scientists led by Nick Indriolo (Space Telescope Science Institute) used EXES to search for signs of hot water molecules moving along with the Becklin-Neugebauer object, and came up empty-handed — adding one more perplexing clue to the mystery of this strange source.

    Hot molecular cores are compact regions of dense gas that represent an intermediary stage of massive star formation; once a protostar forms in a collapsing cloud, it heats its surroundings and drives an outflow of evaporating material.

    A study led by Andrew Barr (Leiden University, the Netherlands) explores the composition of the hot molecular core AFGL 2591 using EXES infrared observations. The authors detect carbon monosulfide (CS), a molecule that can be used to probe the physical conditions deep in the innermost parts of the hot core near the base of the outflow.

    4
    Hubble image of a nearby Young Stellar Object, V1331Cyg. [ESA/NASA/Hubble/K. Stapelfeldt/B. Stecklum/A. Choudhary]

    In another look at sulfur chemistry in massive star formation, Ryan Dungee (Institute for Astronomy, University of Hawaii) and collaborators observed warm sulfur dioxide gas (SO2) near the massive young stellar object (YSO) MonR2 IRS3, a collapsing protostar still embedded in a molecular cloud. The high resolution of EXES’s observations allowed the authors to identify the most likely source of the gas: sublimating ices in the hot core close to the massive young stellar object. These observations help us to understand the underlying chemistry of the birth of massive stars.

    5
    Composite image of Europa from Galileo and Voyager, superimposed on Hubble data that suggests the presence of plumes of water vapor at roughly the 7 o’clock position off Europa’s limb. [NASA/ESA/W. Sparks (STScI)/USGS Astrogeology Science Center]

    NASA/Galileo 1989-2003

    NASA/Voyager 1

    Does Jupiter’s moon Europa host plumes of water erupting from its surface? So suggest Hubble images from 2012 and recently re-analyzed data from NASA’s Galileo spacecraft. To test this theory, a team led by William Sparks (SETI Institute and Space Telescope Science Institute) used SOFIA/EXES to search for direct evidence of the presence of water vapor erupting from Europa’s surface.

    The result? If plumes are indeed present on Europa, they can’t be carrying much water vapor. EXES saw no evidence of plumes, placing an upper limit on the amount of water ejected from the moon in this way during SOFIA’s observations. This limit is lower than the amount of water implied by the previous Hubble observations — leaving yet another mystery unsolved and deepening the question of whether Europa has what it takes to support life.

    Citation

    ApJL Focus issue:
    Focus on New Results from SOFIA

    EXES articles:
    “High Spectral Resolution Observations toward Orion BN at 6 μm: No Evidence for Hot Water,” Nick Indriolo et al. 2018 ApJL 865 L18. doi:10.3847/2041-8213/aae1ff
    “Infrared Detection of Abundant CS in the Hot Core AFGL 2591 at High Spectral Resolution with SOFIA/EXES ,” Andrew G. Barr et al. 2018 ApJL 868 L2. doi:10.3847/2041-8213/aaeb23
    “High-resolution SOFIA/EXES Spectroscopy of SO2 Gas in the Massive Young Stellar Object MonR2 IRS3: Implications for the Sulfur Budget,” Ryan Dungee et al. 2018 ApJL 868 L10. doi:10.3847/2041-8213/aaeda9
    “A Search for Water Vapor Plumes on Europa using SOFIA,” W. B. Sparks et al. 2019 ApJL 871 L5. doi:10.3847/2041-8213/aafb0a

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Societyis to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 11:42 am on May 16, 2019 Permalink | Reply
    Tags: , , , Cosmology, ,   

    From Ethan Siegel: “We Have Now Reached The Limits Of The Hubble Space Telescope” 

    From Ethan Siegel
    May 16, 2019

    1
    The Hubble Space Telescope, as imaged during its last and final servicing mission. The only way it can point itself is from the internal spinning devices that allow it to change its orientation and hold a stable position. But what it can see is determined by its instruments, mirror, and design limitations. It has reached those ultimate limits; to go beyond them, we’ll need a better telescope. (NASA)

    The world’s greatest observatory can go no further with its current instrument set.

    The Hubble Space Telescope has provided humanity with our deepest views of the Universe ever. It has revealed fainter, younger, less-evolved, and more distant stars, galaxies, and galaxy clusters than any other observatory. More than 29 years after its launch, Hubble is still the greatest tool we have for exploring the farthest reaches of the Universe. Wherever astrophysical objects emit starlight, no observatory is better equipped to study them than Hubble.

    But there are limits to what any observatory can see, even Hubble. It’s limited by the size of its mirror, the quality of its instruments, its temperature and wavelength range, and the most universal limiting factor inherent to any astronomical observation: time. Over the past few years, Hubble has released some of the greatest images humanity has ever seen. But it’s unlikely to ever do better; it’s reached its absolute limit. Here’s the story.

    2
    The Hubble Space Telescope (left) is our greatest flagship observatory in astrophysics history, but is much smaller and less powerful than the upcoming James Webb (center). Of the four proposed flagship missions for the 2030s, LUVOIR (right) is by far the most ambitious. By probing the Universe to fainter objects, higher resolution, and across a wider range of wavelengths, we can improve our understanding of the cosmos in unprecedented ways. (MATT MOUNTAIN / AURA)

    NASA/ESA/CSA Webb Telescope annotated

    NASA Large UV Optical Infrared Surveyor (LUVOIR)

    From its location in space, approximately 540 kilometers (336 mi) up, the Hubble Space Telescope has an enormous advantage over ground-based telescopes: it doesn’t have to contend with Earth’s atmosphere. The moving particles making up Earth’s atmosphere provide a turbulent medium that distorts the path of any incoming light, while simultaneously containing molecules that prevent certain wavelengths of light from passing through it entirely.

    While ground-based telescopes at the time could achieve practical resolutions no better than 0.5–1.0 arcseconds, where 1 arcsecond is 1/3600th of a degree, Hubble — once the flaw with its primary mirror was corrected — immediately delivered resolutions down to the theoretical diffraction limit for a telescope of its size: 0.05 arcseconds. Almost instantly, our views of the Universe were sharper than ever before.

    3
    This composite image of a region of the distant Universe (upper left) uses optical (upper right) and near-infrared (lower left) data from Hubble, along with far-infrared (lower right) data from Spitzer. The Spitzer Space Telescope is nearly as large as Hubble: more than a third of its diameter, but the wavelengths it probes are so much longer that its resolution is far worse. The number of wavelengths that fit across the diameter of the primary mirror is what determines the resolution.(NASA/JPL-CALTECH/ESA)

    Sharpness, or resolution, is one of the most important factors in discovering what’s out there in the distant Universe. But there are three others that are just as essential:

    the amount of light-gathering power you have, needed to view the faintest objects possible,
    the field-of-view of your telescope, enabling you to observe a larger number of objects,
    and the wavelength range you’re capable of probing, as the observed light’s wavelength depends the object’s distance from you.

    Hubble may be great at all of these, but it also possesses fundamental limits for all four.

    4
    When you look at a region of the sky with an instrument like the Hubble Space Telescope, you are not simply viewing the light from distant objects as it was when that light was emitted, but also as the light is affected by all the intervening material and the expansion of space, that it experiences along its journey. Although Hubble has taken us farther back than any other observatory to date, there are fundamental limits to it, and reasons why it will be incapable of going farther. (NASA, ESA, AND Z. LEVAY, F. SUMMERS (STSCI))

    The resolution of any telescope is determined by the number of wavelengths of light that can fit across its primary mirror. Hubble’s 2.4 meter (7.9 foot) mirror enables it to obtain that diffraction-limited resolution of 0.05 arcseconds. This is so good that only in the past few years have Earth’s most powerful telescopes, often more than four times as large and equipped with state-of-the-art adaptive optics systems, been able to compete.

    To improve upon the resolution of Hubble, there are really only two options available:

    1. use shorter wavelengths of light, so that a greater number of wavelengths can fit across a mirror of the same size,
    2. or build a larger telescope, which will also enable a greater number of wavelengths to fit across your mirror.

    Hubble’s optics are designed to view ultraviolet light, visible light, and near-infrared light, with sensitivities ranging from approximately 100 nanometers to 1.8 microns in wavelength. It can do no better with its current instruments, which were installed during the final servicing mission back in 2009.

    5
    This image shows Hubble servicing Mission 4 astronauts practice on a Hubble model underwater at the Neutral Buoyancy Lab in Houston under the watchful eyes of NASA engineers and safety divers. The final servicing mission on Hubble was successfully completed 10 years ago; Hubble has not had its equipment or instruments upgraded since, and is now running up against its fundamental limitations. (NASA)

    Light-gathering power is simply about collecting more and more light over a greater period of time, and Hubble has been mind-blowing in that regard. Without the atmosphere to contend with or the Earth’s rotation to worry about, Hubble can simply point to an interesting spot in the sky, apply whichever color/wavelength filter is desired, and take an observation. These observations can then be stacked — or added together — to produce a deep, long-exposure image.

    Using this technique, we can see the distant Universe to unprecedented depths and faintnesses. The Hubble Deep Field was the first demonstration of this technique, revealing thousands of galaxies in a region of space where zero were previously known. At present, the eXtreme Deep Field (XDF) is the deepest ultraviolet-visible-infrared composite, revealing some 5,500 galaxies in a region covering just 1/32,000,000th of the full sky.

    6
    The Hubble eXtreme Deep Field (XDF) may have observed a region of sky just 1/32,000,000th of the total, but was able to uncover a whopping 5,500 galaxies within it: an estimated 10% of the total number of galaxies actually contained in this pencil-beam-style slice. The remaining 90% of galaxies are either too faint or too red or too obscured for Hubble to reveal, and observing for longer periods of time won’t improve this issue by very much. Hubble has reached its limits. (HUDF09 AND HXDF12 TEAMS / E. SIEGEL (PROCESSING))

    Of course, it took 23 days of total data taking to collect the information contained within the XDF. To reveal objects with half the brightness as the faintest objects seen in the XDF, we’d have to continue observing for a total of 92 days: four times as long. There’s a severe trade-off if we were to do this, as it would tie up the telescope for months and would only teach us marginally more about the distant Universe.

    Instead, an alternative strategy for learning more about the distant Universe is to survey a targeted, wide-field area of the sky. Individual galaxies and larger structures like galaxy clusters can be probed with deep but large-area views, revealing a tremendous level of detail about what’s present at the greatest distances of all. Instead of using our observing time to go deeper, we can still go very deep, but cast a much wider net.

    This, too, comes with a tremendous cost. The deepest, widest view of the Universe ever assembled by Hubble took over 250 days of telescope time, and was stitched together from nearly 7,500 individual exposures. While this new Hubble Legacy Field is great for extragalactic astronomy, it still only reveals 265,000 galaxies over a region of sky smaller than that covered by the full Moon.

    Hubble was designed to go deep, but not to go wide. Its field of view is extremely narrow, which makes a larger, more comprehensive survey of the distant Universe all but prohibitive. It’s truly remarkable how far Hubble has taken us in terms of resolution, survey depth, and field-of-view, but Hubble has truly reached its limit on those fronts.

    7
    In the big image at left, the many galaxies of a massive cluster called MACS J1149+2223 dominate the scene. Gravitational lensing by the giant cluster brightened the light from the newfound galaxy, known as MACS 1149-JD, some 15 times. At upper right, a partial zoom-in shows MACS 1149-JD in more detail, and a deeper zoom appears to the lower right. This is correct and consistent with General Relativity, and independent of how we visualize (or whether we visualize) space. (NASA/ESA/STSCI/JHU)

    Finally, there are the wavelength limits as well. Stars emits a wide variety of light, from the ultraviolet through the optical and into the infrared. It’s no coincidence that this is what Hubble was designed for: to look for light that’s of the same variety and wavelengths that we know stars emit.

    But this, too, is fundamentally limiting. You see, as light travels through the Universe, the fabric of space itself is expanding. This causes the light, even if it’s emitted with intrinsically short wavelengths, to have its wavelength stretched by the expansion of space. By the time it arrives at our eyes, it’s redshifted by a particular factor that’s determined by the expansion rate of the Universe and the object’s distance from us.

    Hubble’s wavelength range sets a fundamental limit to how far back we can see: to when the Universe is around 400 million years old, but no earlier.

    8
    The most distant galaxy ever discovered in the known Universe, GN-z11, has its light come to us from 13.4 billion years ago: when the Universe was only 3% its current age: 407 million years old. But there are even more distant galaxies out there, and we all hope that the James Webb Space Telescope will discover them. (NASA, ESA, AND G. BACON (STSCI))

    The most distant galaxy ever discovered by Hubble, GN-z11, is right at this limit. Discovered in one of the deep-field images, it has everything imaginable going for it.

    It was observed across all the different wavelength ranges Hubble is capable of, with only its ultraviolet-emitted light showing up in the longest-wavelength infrared filters Hubble can measure.
    It was gravitationally lensed by a nearby galaxy, magnifying its brightness to raise it above Hubble’s naturally-limiting faintness threshold.
    It happens to be located along a line-of-sight that experienced a high (and statistically-unlikely) level of star-formation at early times, providing a clear path for the emitted light to travel along without being blocked.

    No other galaxy has been discovered and confirmed at even close to the same distance as this object.

    9
    Only because this distant galaxy, GN-z11, is located in a region where the intergalactic medium is mostly reionized, can Hubble reveal it to us at the present time. To see further, we require a better observatory, optimized for these kinds of detection, than Hubble. (NASA, ESA, AND A. FEILD (STSCI))

    Hubble may have reached its limits, but future observatories will take us far beyond what Hubble’s limits are. The James Webb Space Telescope is not only larger — with a primary mirror diameter of 6.5 meters (as opposed to Hubble’s 2.4 meters) — but operates at far cooler temperatures, enabling it to view longer wavelengths.

    At these longer wavelengths, up to 30 microns (as opposed to Hubble’s 1.8), James Webb will be able to see through the light-blocking dust that hampers Hubble’s view of most of the Universe. Additionally, it will be able to see objects with much greater redshifts and earlier lookback times: seeing the Universe when it was a mere 200 million years old. While Hubble might reveal some extremely early galaxies, James Webb might reveal them as they’re in the process of forming for the very first time.

    10
    The viewing area of Hubble (top left) as compared to the area that WFIRST will be able to view, at the same depth, in the same amount of time. The wide-field view of WFIRST will allow us to capture a greater number of distant supernovae than ever before, and will enable us to perform deep, wide surveys of galaxies on cosmic scales never probed before. It will bring a revolution in science, regardless of what it finds, and provide the best constraints on how dark energy evolves over cosmic time. (NASA / GODDARD / WFIRST)

    NASA/WFIRST

    Other observatories will take us to other frontiers in realms where Hubble is only scratching the surface. NASA’s proposed flagship of the 2020s, WFIRST, will be very similar to Hubble, but will have 50 times the field-of-view, making it ideal for large surveys. Telescopes like the LSST will cover nearly the entire sky, with resolutions comparable to what Hubble achieves, albeit with shorter observing times. And future ground-based observatories like GMT or ELT, which will usher in the era of 30-meter-class telescopes, might finally surpass Hubble in terms of practical resolution.

    At the limits of what Hubble is capable of, it’s still extending our views into the distant Universe, and providing the data that enables astronomers to push the frontiers of what is known. But to truly go farther, we need better tools. If we truly value learning the secrets of the Universe, including what it’s made of, how it came to be the way it is today, and what its fate is, there’s no substitute for the next generation of observatories.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

     
  • richardmitnick 9:53 am on May 16, 2019 Permalink | Reply
    Tags: "ALMA Discovers Aluminum around a Young Star", , , , , Cosmology, ,   

    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

    1

    2
    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.

    NRAO Small
    ESO 50 Large

     
  • richardmitnick 9:18 am on May 16, 2019 Permalink | Reply
    Tags: "Hubble Observes Creative Destruction as Galaxies Collide", , , , Cosmology, Irregular galaxy NGC 4485,   

    From NASA/ESA Hubble Telescope: “Hubble Observes Creative Destruction as Galaxies Collide” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    16 May 2019
    Bethany Downer
    ESA/Hubble, Public Information Officer
    Garching, Germany
    Email: bethany.downer@partner.eso.org

    Ray Villard
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4514
    villard@stsci.edu

    1
    The NASA/ESA Hubble Space Telescope has taken a new look at the spectacular irregular galaxy NGC 4485, which has been warped and wound by its larger galactic neighbour. The gravity of the second galaxy has disrupted the ordered collection of stars, gas and dust, giving rise to an erratic region of newborn, hot, blue stars and chaotic clumps and streams of dust and gas.

    2
    NGC 4485 has been involved in a dramatic gravitational interplay with its larger galactic neighbour NGC 4490 — out of frame to the bottom right in this image. This ruined the original, ordered spiral structure of the galaxy and transformed it into an irregular one. The interaction also created a stream of material about 25 000 light-years long, connecting the two galaxies. The stream, visible to the right of the galaxy is made up of bright knots and huge pockets of gassy regions, as well as enormous regions of star formation in which young, massive, blue stars are born. Below NGC 4485 one can see a bright, orange background galaxy: CXOU J123033.6+414057. This galaxy is the source of X-ray radiation studied by the Chandra X-ray Observatory. It’s distance from Earth is about 850 million light-years.

    NASA/Chandra X-ray Telescope

    The irregular galaxy NGC 4485 has been involved in a dramatic gravitational interplay with its larger galactic neighbour NGC 4490 — out of frame to the bottom right in the top image. Found about 30 million light-years away in the constellation of Canes Venatici (the Hunting Dogs), the strange result of these interacting galaxies has resulted in an entry in the Atlas of Peculiar galaxies: Arp 269.

    Having already made their closest approach, NGC 4485 and NGC 4490 are now moving away from each other, vastly altered from their original states. Still engaged in a destructive yet creative dance, the gravitational force between them continues to warp each of them out of all recognition, while at the same time creating the conditions for huge regions of intense star formation.

    This galactic tug-of-war has created a stream of material about 25 000 light-years long which connects the two galaxies. The stream is made up of bright knots and huge pockets of gassy regions, as well as enormous regions of star formation in which young, massive, blue stars are born. Short-lived, however, these stars quickly run out of fuel and end their lives in dramatic explosions. While such an event seems to be purely destructive, it also enriches the cosmic environment with heavier elements and delivers new material to form a new generation of stars.

    Two very different regions are now apparent in NGC 4485; on the left are hints of the galaxy’s previous spiral structure, which was at one time undergoing “normal” galactic evolution. The right of the image reveals a portion of the galaxy ripped towards its larger neighbour, bursting with hot, blue stars and streams of dust and gas.

    This image, captured by the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope, adds light through two new filters compared with an image released in 2014. The new data provide further insights into the complex and mysterious field of galaxy evolution.

    NASA/ESA Hubble WFC3

    See the full ESA/Hubble article here .
    See the full HubbleSite article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

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  • richardmitnick 1:28 pm on May 15, 2019 Permalink | Reply
    Tags: "Focus on SOFIA: FIFI-LS", , , , , Cosmology   

    From AAS NOVA: “Focus on SOFIA: FIFI-LS” 

    AASNOVA

    From AAS NOVA

    15 May 2019
    Susanna Kohler

    1
    This composite X-ray, optical, radio, and infrared image captures the active galaxy NGC 4258. SOFIA/FIFI-LS observations of the core of this galaxy reveal a molecular tracer associated with the energetic outflows from the galactic nucleus. [X-ray: NASA/CXC/Caltech/P.Ogle et al; Optical: NASA/STScI & R.Gendler; IR: NASA/JPL-Caltech; Radio: NSF/NRAO/VLA]

    NASA/ESA Hubble Telescope

    NASA/Chandra X-ray Telescope

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

    In December, AAS Nova Editor Susanna Kohler had the opportunity to fly aboard the NASA/DLR Stratospheric Observatory for Infrared Astronomy (SOFIA). This week we’re taking a look at that flight, as well as some of the recent science the observatory produced and published in an ApJ Letters Focus Issue.

    One of SOFIA’s great strengths is that the instruments mounted on this flying telescope can be easily swapped out, allowing for a broad range of infrared observations. Three of SOFIA’s instruments are featured in science recently published in the ApJ Letters Focus Issue: the Far Infrared Field-Imaging Line Spectrometer (FIFI-LS), the High-Resolution Airborne Wideband Camera Plus (HAWC+), and the Echelon-Cross-Echelle Spectrograph (EXES).

    2
    The FIFI-LS instrument mounted on the SOFIA telescope. [NASA/SOFIA/USRA/Greg Perryman]

    By simultaneously capturing both images and spectra, FIFI-LS is able to deeply probe the composition and physical properties (like pressure and temperature) of heavily dust-obscured, star-forming regions in our own galaxy, as well as those in nearby external galaxies and galactic nuclei.

    Some Recent FIFI-LS Science

    In a study led by Gerold Busch (University of Cologne, Germany), scientists detail the first detection with FIFI-LS of a nearby luminous AGN, or active galactic nucleus. Despite its relative nearness, this galaxy is still roughly 500 million light-years away, making it the most distant object ever studied with SOFIA.
    The team compares FIFI-LS’s spatially resolved observations of the infrared emission line [CII] in the galaxy to optical observations of Hα, an emission line known to trace star formation. By demonstrating that the two different types of emission occur in the same places in the galaxy, the team shows that [CII] emission can be used as a powerful diagnostic tool for tracing star formation even in distant galaxies — and even when those galaxies host luminous active nuclei.

    3
    Left: FIFI-LS image of [CII] emission from M51. Right: X-ray, optical, and infrared composite image of M51. The deficit of [CII] emission from the upper companion galaxy suggests it has a much lower star formation rate. [Left: Adapted from Pineda et al. 2018; Right: X-ray: NASA/CXC/SAO; Optical: Detlef Hartmann; Infrared: NASA/JPL-Caltech]

    A publication led by Jorge Pineda (Jet Propulsion Laboratory) details a SOFIA-produced map of [CII] emission in the spectacular grand design galaxy M51 and the small companion galaxy M51b with which it is merging. The map reveals a deficit of [CII] emission in the companion galaxy, suggesting this small galaxy isn’t forming stars at the same rate as its larger cousin.

    The molecular cloud BYF 73 is currently collapsing in on itself, making it a promising target in which to watch the formation of massive stars. In a study led by Rebecca Pitts (University of Florida), scientists have gathered multi-wavelength observations of this nursery, including mid-infrared data from FIFI-LS. The observations reveal the presence of eight very young (around just 7,000 years old), very massive protostars (the largest is ~240 times the mass of the Sun) embedded in the center of the cloud — providing an excellent opportunity to learn about the early stages of massive star formation.

    4
    A zoomed-out (left) and zoomed-in (right) view of NGC 4258’s center, with contours of the [CII] emission superimposed on false-color representations of Hubble data. The [CII] emission is associated with the shocks and turbulence in the galaxy’s jets, which are marked by the line ending in two circles. [Appleton et al. 2018]

    [CII] emission doesn’t just trace star formation! In a study led by Phil Appleton (IPAC/Caltech), scientists have used FIFI-LS’s observations of the active galaxy NGC 4258 to show that [CII] emission is also associated with warm molecular gas and soft X-ray hotspots, both created by shocks and turbulence in the speeding jets launched from the center of an active galaxy. These observations demonstrate that we can use [CII] emission to learn about how these energetic outflows interact with their environments.

    Citation

    ApJL Focus Issue:
    Focus on New Results from SOFIA

    FIFI-LS articles:

    “The Close AGN Reference Survey (CARS): SOFIA Detects Spatially Resolved [C ii] Emission in the Luminous AGN HE 0433-1028,” G. Busch et al. 2018 ApJL 866 L9. doi:10.3847/2041-8213/aae25d
    “A SOFIA Survey of [C ii] in the Galaxy M51. I. [C ii] as a Tracer of Star Formation,” Jorge L. Pineda et al. 2018 ApJL 869 L30. doi:10.3847/2041-8213/aaf1ad
    “Gemini, SOFIA, and ATCA Reveal Very Young, Massive Protostars in the Collapsing Molecular Cloud BYF 73,” Rebecca L. Pitts et al. 2018 ApJL 867 L7. doi:10.3847/2041-8213/aae6ce
    “SOFIA FIFI-LS Observations of Sgr B1: Ionization Structure and Sources of Excitation,” Janet P. Simpson et al. 2018 ApJL 867 L13. doi:10.3847/2041-8213/aae8e4
    “Jet-related Excitation of the [C ii] Emission in the Active Galaxy NGC 4258 with SOFIA,” P. N. Appleton et al. 2018 ApJ 869 61. doi:10.3847/1538-4357/aaed2a

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Societyis to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 8:33 am on May 15, 2019 Permalink | Reply
    Tags: , , , Cosmology, From Max Planck Institute for Astronomy, IllustrisTNG family of simulations   

    From Max Planck Institute for Astronomy: “A (simulated) Universe for Everybody – IllustrisTNG releases Petabyte data set” 

    From Max Planck Institute for Astronomy

    May 14, 2019

    Annalisa Pillepich
    Independent Research Group Leader
    Phone: +49 6221 528-395
    Email: pillepich@mpia-hd.mpg.de
    Room: 121

    Markus Pössel
    Public Information Officer
    Phone:+49 6221 528-261
    pr@mpia.de

    1
    The TNG simulations model the universe from the large-scale cosmic structure right down to the substructure of galaxies. Image: Illustris-TNG

    One of the largest and most detailed simulations of the cosmos has released most of its data to the public, as described in an article that has just been published.

    The IllustrisTNG family of simulations is the closest astronomers have yet gotten to recreating a whole universe in a computer. These simulations include not only the ubiquitous Dark Matter, believed to be the most common form of matter in our cosmos, but gas in and between galaxies, stars, and even large-scale magnetic fields.

    Now, in what is one of the largest astronomical data sets ever released, the IllustrisTNG team are making more than 1 Petabyte of their data available to the public. One Petabyte corresponds to 1000 Terabytes, or a million Gigabytes. Users can register at http://www.tng-project.org/data/ to obtain access to the data.

    The IllustrisTNG simulation is special for the diversity of length scales it includes: Not only the largest possible structures in the cosmos, tens of millions of light-years, but details right down to the scale of structures within galaxies, less than a few thousand light-years. This makes for diverse applications within astronomy – from studies of the large-scale structure of the universe to studies of galaxy formation, star formation within galaxies, or the intergalactic medium.

    The data release is accompanied by an accompanying article in the journal Computational Astrophysics and Cosmology, which has just been published. The current data release concerns the TNG300 and TNG100 data sets; the even more fine-grained simulation TNG50 will follow in due course. The data sets themselves have been available to the public since December 2018. The data is not only available for download, but can also be explored interactively, using a Google-Map-Like online interface and even a three-dimensional fly-through representation of the galactic halos within the IllustrisTNG universe, accessible at http://www.tng-project.org/explore/
    Links

    Illustris-TNG website
    TNG Data Exploration pages

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Max Planck Institute for Astronomy campus

    The Max Planck Institute for Astronomy

    How do stars and planets form? What can we learn about planets orbiting stars other than the Sun? How do galaxies form, and how have they changed in the course of cosmic history?

    Those are the central questions guiding the work of the scientists and engineers at the Max Planck Institute for Astronomy (MPIA) in Heidelberg. The institute was founded in 1967, and it is one of roughly 80 institutes of the Max Planck Society, Germany’s largest organizations for basic research.

    MPIA has a staff of around 290, three quarters of which are working in sci-tech. At any given time, the institute features numerous junior scientists and guest scientists both from Germany and abroad.

     
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