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  • richardmitnick 8:53 pm on September 16, 2019 Permalink | Reply
    Tags: , , , Cosmology, , the most massive neutron star yet J0740+6620   

    From PBS NOVA: “Astronomers may have just detected the most massive neutron star yet” 

    From PBS NOVA

    September 16, 2019
    Katherine J. Wu

    1
    An artist’s impression of the pulse from a neutron star being delayed by a white dwarf passing between the neutron star and Earth. Image Credit: BSaxton, NRAO/AUI/NSF

    1

    The sun at the center of our solar system is a big-bodied behemoth, clocking in at more than 4 nonillion pounds (in the U.S., that’s 4 followed by 30 zeros).

    Now, multiply that mass by 2.14, and cram it down into a ball just 15 miles across. That’s an absurdly dense object, one almost too dense to exist. But the key word here is “almost”—because a team of astronomers has just found one such star.

    The newly discovered cosmic improbability, reported today in the journal Nature Astronomy, is a neutron star called J0740+6620 that lurks 4,600 light-years from Earth. It’s the most massive neutron star ever detected, and is likely to remain a top contender for that title for some time: Much denser, researchers theorize, and it would collapse into a black hole.

    Both neutron stars and black holes are stellar corpses—the leftover cores of stars that die in cataclysmic explosions called supernovae. The density of these remnants dictates their fate: The more mass that’s stuffed into a small space, the more likely a black hole will form.

    Neutron stars are still ultra-dense, though, and astronomers don’t have a clear-cut understanding of how matter behaves within them. Extremely massive neutron stars like this one, which exist tantalizingly close to the black hole tipping point, could yield some answers, study author Thankful Cromartie, an astronomer at the University of Virginia, told Ryan F. Mandelbaum at Gizmodo.

    Cromartie and her colleagues first detected J0740+6620, which is a type of rapidly rotating neutron star called a millisecond pulsar, with the Green Bank telescope in West Virginia. The name arises from the way the spinning star’s poles emit radio waves, generating a pulsing pattern that mimics the sweeping motion of a lighthouse beam.

    During their observations, the researchers noted that J0740+6620 is locked into a tight dance with a white dwarf—another kind of dense stellar remnant. The two bodies orbit each other, forming what’s called a binary. When the white dwarf passes in front of the pulsar from our point of view, it forces light from J0740+6620 to take a slightly longer path to Earth, because the white dwarf’s gravity slightly warps the space around it. The team used the delay in J0740+6620’s pulses to calculate the mass of both objects.

    Previous measurements from the Laser Interferometer Gravitational-Wave Observatory (LIGO) suggest that the upper limit for a neutron star’s mass is about 2.17 times that of the sun—a figure that’s just a smidge above J0740+6620’s estimated heft. But with future observations, that number could still change.

    MIT /Caltech Advanced aLigo

    Harshal Gupta, NSF program director for the Green Bank Observatory, called the new paper “a very solid effort in terms of astronomy and the physics of compact objects,” Mandelbaum reports.

    “Each ‘most massive’ neutron star we find brings us closer to identifying that tipping point [when they must collapse],” study author Scott Ransom, an astronomer at the National Radio Astronomy Observatory, said in a statement. “The orientation of this binary star system created a fantastic cosmic laboratory.”

    See the full article here .

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    NOVA is the highest rated science series on television and the most watched documentary series on public television. It is also one of television’s most acclaimed series, having won every major television award, most of them many times over.

     
  • richardmitnick 5:29 pm on September 14, 2019 Permalink | Reply
    Tags: , , , , Cosmology, ,   

    From Symmetry: “A new way to study high-energy gamma rays” 

    From Symmetry

    09/03/19
    Jim Daley

    The Čerenkov Telescope Array will combine experimental and observatory-style approaches to investigate the universe’s highest energies.

    1

    They permeate the cosmos, whizzing through galaxies and solar systems at energies far higher than what even our most powerful particle accelerators can achieve. Emitted by sources such as far-distant quasars, or, closer to Earth, occasionally ejected from the remnants of supernovae, high-energy cosmic rays are believed to play a role in the evolution of galaxies and the growth of black holes.

    Exactly how cosmic rays originate remains a mystery. Now, an ambitious project—part observatory, part experiment—is preparing to investigate them by studying the gamma rays they produce at sensitivities never achieved before.

    The Čerenkov Telescope Array being built in Chile and Spain’s Canary Islands is the newest generation of ground-based gamma-ray detectors. CTA involves collaborators from 31 countries and comprises more than 100 telescopes of varying sizes. Its detectors will be 10 times more sensitive to gamma rays than existing instruments, which will allow scientists to investigate their properties at a breathtaking range of energy levels—from about 20 billion electronvolts up to 300 trillion electronvolts. This is far above current capabilities: Existing gamma-ray observatories’ energy ranges top out at about 50 trillion electronvolts.

    Rene Ong, an astrophysicist at UCLA and the co-spokesperson for the project, says that CTA is unique in that it will function as both an experiment—zeroing in to investigate specific points and topics of interest—and an observatory—creating an overall record of a portion of the night sky over time.

    It will be the first ground-based gamma-ray observatory, and users will be granted observatory access time for their own projects in a proposal-driven program. “CTA will operate like an astronomical facility with a mix of guest-observer time, dedicated time for major observation projects, and time reserved for the CTA observatory director,” he says.

    Part of what makes CTA an astronomical observatory is that it will make its data freely available, explains Ulisses Barres, an astrophysicist at the Brazilian Center for Physical Research who is leading part of that country’s contribution to CTA’s design and construction.

    Until now, very-high-energy gamma-ray band astronomy research has been conducted by “closed” research groups, which have reserved most or all of their data for their own use. CTA will not only make its data public; just like a typical observatory, it will also structure its data to make it accessible even to nonspecialists and people in other scientific fields.

    “That’s because CTA wants to kind of kick-start astronomy in the [high-energy gamma-ray] band in a new way,” Barres says. “People from other fields can request data from CTA in a competitive way and analyze it, pretty much like what an experimental telescope does.”

    Elisabete de Gouveia Dal Pino, an astrophysicist at the University of São Paulo and also one of the leaders of the CTA Consortium in Brazil, says the project’s design will allow scientists to investigate some of the most energetic events that occur anywhere in the universe. These events are theorized to come mostly from compact sources like supermassive black holes and supernovae explosions.

    “There is a whole slew of processes and particles that we can decipher [by] observing the universe in gamma rays,” Dal Pino says. Other wavelengths have already been probed and are well-developed fields of study, she explains. “This is the last energy band window that we are currently able to open on the universe right now.”

    CTA may also test physics beyond the Standard Model, Ong says. In particular, it will search for dark matter, which scientists think makes up 85% of the known matter in the universe but has yet to be detected, let alone fully understood. It’s possible that gamma rays are produced when dark matter particles bump into one another and self-annihilate.

    CTA’s dark matter program will attempt to discover the nature of this phenomenon by observing the galactic halo, a roughly spherical, thinly populated area that surrounds the visible galaxy and is believed to be home to these particles.

    For now, the project is still in its design and construction phase. Barres says he expects a “critical mass” of telescopes—enough to begin taking useable data—in the northern hemisphere by 2022. “We expect that by the middle of the next decade, CTA may already be fully operational,” he says. “For now, there is a lot of coordination to be done among the partner institutions.”

    See the full article here .


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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 4:52 pm on September 14, 2019 Permalink | Reply
    Tags: , , , Cosmology, , ,   

    From Lawrence Livermore National Laboratory: “World’s largest optical lens shipped to SLAC” 

    From Lawrence Livermore National Laboratory

    Sept. 12, 2019

    Stephen Wampler
    wampler1@llnl.gov
    925-423-3107

    1
    LLNL engineer Vincent Riot (left), who has worked on the Large Synoptic Survey Telescope (LSST) for more than a decade and has been the full camera project manager since 2017, and LLNL optical engineer Justin Wolfe, the LSST camera optics subsystems manager, stand in front of the LSST main lens assembly. Photo by Farrin Abbott/SLAC National Accelerator Laboratory.

    When the world’s newest telescope starts imaging the southern sky in 2023, it will take photos using optical assemblies designed by Lawrence Livermore National Laboratory (LLNL) researchers and built by Lab industrial partners.

    A key feature of the camera’s optical assemblies for the Large Synoptic Survey Telescope (LSST), under construction in northern Chile, will be its three lenses, one of which at 1.57 meters (5.1 feet) in diameter is believed to be the world’s largest high-performance optical lens ever fabricated.

    The lens assembly, which includes the lens dubbed L-1, and its smaller companion lens (L-2), at 1.2 meters in diameter, was built over the past five years by Boulder, Colorado-based Ball Aerospace and its subcontractor, Tucson-based Arizona Optical Systems.

    Mounted together in a carbon fiber structure, the two lenses were shipped from Tucson, arriving intact after a 17-hour truck journey at the SLAC National Accelerator Laboratory in Menlo Park.

    SLAC is managing the overall design and fabrication, as well as the subcomponent integration and final assembly of LSST’s $168 million, 3,200-megapixel digital camera, which is more than 90 percent complete and due to be finished by early 2021. In addition to SLAC and LLNL, the team building the camera includes an international collaboration of universities and labs, including the Paris-based Centre National de la Recherche Scientifique and Brookhaven National Laboratory.

    LSST the Vera C. Rubin Observatory

    LSST Camera, built at SLAC

    LSST telescope, currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    LSST Data Journey, Illustration by Sandbox Studio, Chicago with Ana Kova

    “The success of the fabrication of this unique optical assembly is a testament to LLNL’s world-leading expertise in large optics, built on decades of experience in the construction of the world’s largest and most powerful laser systems,” said physicist Scot Olivier, who helped manage Livermore’s involvement in the LSST project for more than a decade.

    Olivier said without the dedicated and exceptional work of LLNL optical scientists Lynn Seppala and Brian Bauman and LLNL engineers Vincent Riot, Scott Winters and Justin Wolfe, spanning a period of nearly two decades, the LSST camera optics, including the world’s largest lens, would not be the reality they are today.

    “Riot’s contributions to LSST also go far beyond the camera optics — as the current overall project manager for the LSST camera, Riot is a principal figure in the successful development of this major scientific instrument that is poised to revolutionize the field of astronomy,” Olivier added.

    LSST Director Steven Kahn, a physicist at Stanford University and SLAC, noted that “Livermore has played a very significant technical role in the camera and a historically important role in the telescope design.”

    Livermore’s researchers made essential contributions to the optical design of LSST’s lenses and mirrors, the way LSST will survey the sky, how it compensates for atmospheric turbulence and gravity, and more.

    LLNL personnel led the procurement and delivery of the camera’s optical assemblies, which include the three lenses (the third lens, at 72 centimeters in diameter, will be delivered to SLAC within a month) and a set of filters covering six wavelength-bands, all in their final mechanical mount.

    Livermore focused on the design and then delegated fabrication to industry vendors, although the filters will be placed into the interface mounts at the Lab before being shipped to SLAC for final integration into the camera.

    The 8.4-meter LSST will take digital images of the entire visible southern sky every few nights, revealing unprecedented details of the universe and helping unravel some of its greatest mysteries. During a 10-year time frame, LSST will detect about 20 billion galaxies — the first time a telescope will observe more galaxies than there are people on Earth – and will create a time-lapse “movie” of the sky.

    This data will help researchers better understand dark matter and dark energy, which together make up 95 percent of the universe, but whose makeup remains unknown, as well as study the formation of galaxies, track potentially hazardous asteroids and observe exploding stars.

    The telescope’s camera — the size of a small car and weighing more than three tons — will capture full-sky images at such high resolution that it would take 1,500 high-definition television screens to display just one picture.

    Research scientists aren’t the only ones who will have access to the LSST data. Anyone with a computer will be able to fly through the universe, past objects 100 million times fainter than can be observed with the unaided eye. The LSST project will provide an engagement platform to enable both students and the public to participate in the process of scientific discovery.

    Riot, who started on the LSST project in 2008, initially managed the camera optics fabrication planning, became the LSST deputy camera manager in 2013 and the full camera project manager in 2017. For the past three years, he has worked at LLNL and at SLAC on special assignment.

    “There are important challenges getting everything together for the LSST camera. We’re receiving all of these expensive parts that people have been working on for years and they all have to fit together,” Riot said.

    Wolfe, an LLNL optical engineer and the LSST camera optics subsystems manager, and Riot are pleased that the world’s largest optical lens has overcome hurdles.

    “Any time you undertake an activity for the first time, there are bound to be challenges, and production of the LSST L-1 lens proved to be no different,” Wolfe said. “Every stage was crucial and carried great risk. You are working with a piece of glass more than five feet in diameter and only four inches thick. Any mishandling, shock or accident can result in damage to the lens. The lens is a work of craftsmanship and we are all rightly proud of it.

    “When I joined LLNL I had no idea that it would lead to the opportunity to deliver first-of-a-kind optics to a first-of-a-kind telescope,” Wolfe said. “From production of the largest precision lens known, to coating of the largest precision bandpass filters, the LSST optics have set a new standard.”

    Livermore involvement in LSST started around 2001, spurred by the scientific interest of LLNL astrophysicist Kem Cook, a member of the Lab team that previously led the search for galactic dark matter in the form of Massive Compact Halo Objects.

    However, LLNL participation in LSST quickly became centered on the Lab’s expertise in large optics, built over decades of developing the world’s largest laser systems. Starting in 2002, LLNL optical scientist Seppala, who helped design the National Ignition Facility, made a series of improvements to the optical design of LSST leading to the 2005 baseline design. This consisted of three mirrors, the two largest in the same plane so they could be fabricated from the same piece of glass, and three large lenses, as well as a set of six filters that define the color of the images recorded by the 3.2-gigapixel camera detector.

    Construction on LSST started in 2014 on El Peñon, a peak 8,800 feet high along the Cerro Pachón ridge in the Andes Mountains, located 220 miles north of Santiago, Chile.

    Financial support for LSST comes from the National Science Foundation (NSF), the U.S. Department of Energy’s Office of Science, and private funding raised by the LSST Corporation. The NSF-funded LSST Project Office for construction was established as an operating center under management of the Association of Universities for Research in Astronomy. The DOE-funded effort to build the LSST camera is managed by the SLAC National Accelerator Laboratory.

    The camera system for LSST, including the three lenses and six filters designed by LLNL researchers and built by Lab industrial partners, will be shipped from SLAC to the telescope site in Chile in early 2021

    See the full article here .


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    LLNL Campus

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security Administration
    Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952. A Federally Funded Research and Development Center (FFRDC), it is primarily funded by the U.S. Department of Energy (DOE) and managed and operated by Lawrence Livermore National Security, LLC (LLNS), a partnership of the University of California, Bechtel, BWX Technologies, AECOM, and Battelle Memorial Institute in affiliation with the Texas A&M University System. In 2012, the laboratory had the synthetic chemical element livermorium named after it.
    LLNL is self-described as “a premier research and development institution for science and technology applied to national security.” Its principal responsibility is ensuring the safety, security and reliability of the nation’s nuclear weapons through the application of advanced science, engineering and technology. The Laboratory also applies its special expertise and multidisciplinary capabilities to preventing the proliferation and use of weapons of mass destruction, bolstering homeland security and solving other nationally important problems, including energy and environmental security, basic science and economic competitiveness.

    The Laboratory is located on a one-square-mile (2.6 km2) site at the eastern edge of Livermore. It also operates a 7,000 acres (28 km2) remote experimental test site, called Site 300, situated about 15 miles (24 km) southeast of the main lab site. LLNL has an annual budget of about $1.5 billion and a staff of roughly 5,800 employees.

    LLNL was established in 1952 as the University of California Radiation Laboratory at Livermore, an offshoot of the existing UC Radiation Laboratory at Berkeley. It was intended to spur innovation and provide competition to the nuclear weapon design laboratory at Los Alamos in New Mexico, home of the Manhattan Project that developed the first atomic weapons. Edward Teller and Ernest Lawrence,[2] director of the Radiation Laboratory at Berkeley, are regarded as the co-founders of the Livermore facility.

    The new laboratory was sited at a former naval air station of World War II. It was already home to several UC Radiation Laboratory projects that were too large for its location in the Berkeley Hills above the UC campus, including one of the first experiments in the magnetic approach to confined thermonuclear reactions (i.e. fusion). About half an hour southeast of Berkeley, the Livermore site provided much greater security for classified projects than an urban university campus.

    Lawrence tapped 32-year-old Herbert York, a former graduate student of his, to run Livermore. Under York, the Lab had four main programs: Project Sherwood (the magnetic-fusion program), Project Whitney (the weapons-design program), diagnostic weapon experiments (both for the Los Alamos and Livermore laboratories), and a basic physics program. York and the new lab embraced the Lawrence “big science” approach, tackling challenging projects with physicists, chemists, engineers, and computational scientists working together in multidisciplinary teams. Lawrence died in August 1958 and shortly after, the university’s board of regents named both laboratories for him, as the Lawrence Radiation Laboratory.

    Historically, the Berkeley and Livermore laboratories have had very close relationships on research projects, business operations, and staff. The Livermore Lab was established initially as a branch of the Berkeley laboratory. The Livermore lab was not officially severed administratively from the Berkeley lab until 1971. To this day, in official planning documents and records, Lawrence Berkeley National Laboratory is designated as Site 100, Lawrence Livermore National Lab as Site 200, and LLNL’s remote test location as Site 300.[3]

    The laboratory was renamed Lawrence Livermore Laboratory (LLL) in 1971. On October 1, 2007 LLNS assumed management of LLNL from the University of California, which had exclusively managed and operated the Laboratory since its inception 55 years before. The laboratory was honored in 2012 by having the synthetic chemical element livermorium named after it. The LLNS takeover of the laboratory has been controversial. In May 2013, an Alameda County jury awarded over $2.7 million to five former laboratory employees who were among 430 employees LLNS laid off during 2008.[4] The jury found that LLNS breached a contractual obligation to terminate the employees only for “reasonable cause.”[5] The five plaintiffs also have pending age discrimination claims against LLNS, which will be heard by a different jury in a separate trial.[6] There are 125 co-plaintiffs awaiting trial on similar claims against LLNS.[7] The May 2008 layoff was the first layoff at the laboratory in nearly 40 years.[6]

    On March 14, 2011, the City of Livermore officially expanded the city’s boundaries to annex LLNL and move it within the city limits. The unanimous vote by the Livermore city council expanded Livermore’s southeastern boundaries to cover 15 land parcels covering 1,057 acres (4.28 km2) that comprise the LLNL site. The site was formerly an unincorporated area of Alameda County. The LLNL campus continues to be owned by the federal government.

    LLNL/NIF


    DOE Seal
    NNSA

     
  • richardmitnick 11:57 am on September 14, 2019 Permalink | Reply
    Tags: , , , , Cosmology, , , , ,   

    From from the University of Melbourne and Australia’s ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) via COSMOS: “The hunt for a 12-billion-year-old signal” 

    From

    u-melbourne-bloc

    From University of Melbourne

    and

    arc-centers-of-excellence-bloc

    From ARC Centres of Excellence

    via

    10 September 2019
    Nick Carne

    1
    In this image the Epoch of Reionization, neutral hydrogen, in red, is gradually ionised by the first stars, shown in white.
    Paul Giel and Simon Mutch / UNIVERSITY OF MELBOURNE DARK-AGES REIONIZATION AND GALAXY OBSERVABLES FROM NUMERICAL SIMULATIONS (DRAGONS) PROGRAM

    Astronomers believe they are closing in on a signal that has been travelling across the Universe for 12 billion years.

    In a paper soon to be published in The Astrophysical Journal, an international team reports a 10-fold improvement on data gathered by the Murchison Widefield Array (MWA), a collection of 4096 dipole antennas set in the remote hinterland of Western Australia.

    SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO)

    The MWA was built specifically to detect electromagnetic radiation emitted by neutral hydrogen – a gas that made up most of the infant Universe in the period when the soup of disconnected protons and neutrons spawned by the Big Bang started to cool down.

    Eventually those atoms began to clump together to form the very first stars, initiating the major phase in the evolution of the Universe known as the Epoch of Reionization, or EoR.

    2
    Epoch of Reionization. Caltech/NASA

    “Defining the evolution of the EoR is extremely important for our understanding of astrophysics and cosmology,” says research leader Nichole Barry from the University of Melbourne and Australia’s ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D).

    “So far, though, no one has been able to observe it. These results take us a lot closer to that goal.”

    The neutral hydrogen that dominated space and time before and in the early period of the EoR radiated at a wavelength of approximately 21 centimetres.

    Stretched now to somewhere above two metres because of the expansion of the Universe, the signal persists – and detecting it remains the theoretical best way to probe conditions in the early days of the Cosmos.

    But that’s difficult to do, the researchers say, as the signal is old and weak and there are a lot of other galaxies in the way.

    That means the signals recorded by the MWA and other EoR-hunting devices, such as the Hydrogen Epoch of Reionisation Array (HERA) in South Africa and the Low Frequency Array (LOFAR) in The Netherlands, are extremely messy.

    UC Berkeley Hydrogen Epoch of Reionization Array (HERA), South Africa

    ASTRON LOFAR Radio Antenna Bank, Netherlands

    Using 21 hours of raw data, Barry and colleagues explored new techniques to refine analysis and exclude consistent sources of signal contamination, including ultra-faint interference generated by radio broadcasts on Earth.

    The result was a level of precision that significantly reduced the range in which the EoR may have begun, pulling in constraints by almost an order of magnitude.

    “We can’t really say that this paper gets us closer to precisely dating the start or finish of the EoR, but it does rule out some of the more extreme models,” says co-author Cathryn Trott, from Australia’s Curtin University.

    “That it happened very rapidly is now ruled out. That the conditions were very cold is now also ruled out.”

    The research was conducted by researchers from a number of institutions in Australia and New Zealand, in collaboration with Arizona State University, Brown University and MIT in the US, Kumamoto University in Japan, and Raman Research Institute in India.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The objectives for the ARC Centres of Excellence are to:

    undertake highly innovative and potentially transformational research that aims to achieve international standing in the fields of research envisaged and leads to a significant advancement of capabilities and knowledge
    link existing Australian research strengths and build critical mass with new capacity for interdisciplinary, collaborative approaches to address the most challenging and significant research problems
    develope relationships and build new networks with major national and international centres and research programs to help strengthen research, achieve global competitiveness and gain recognition for Australian research
    build Australia’s human capacity in a range of research areas by attracting and retaining, from within Australia and abroad, researchers of high international standing as well as the most promising research students
    provide high-quality postgraduate and postdoctoral training environments for the next generation of researchers
    offer Australian researchers opportunities to work on large-scale problems over long periods of time
    establish Centres that have an impact on the wider community through interaction with higher education institutes, governments, industry and the private and non-profit sector.

    u-melbourne-campus

    The University of Melbourne (informally Melbourne University) is an Australian public research university located in Melbourne, Victoria. Founded in 1853, it is Australia’s second oldest university and the oldest in Victoria. Times Higher Education ranks Melbourne as 33rd in the world, while the Academic Ranking of World Universities places Melbourne 44th in the world (both first in Australia).

    Melbourne’s main campus is located in Parkville, an inner suburb north of the Melbourne central business district, with several other campuses located across Victoria. Melbourne is a sandstone university and a member of the Group of Eight, Universitas 21 and the Association of Pacific Rim Universities. Since 1872 various residential colleges have become affiliated with the university. There are 12 colleges located on the main campus and in nearby suburbs offering academic, sporting and cultural programs alongside accommodation for Melbourne students and faculty.

    Melbourne comprises 11 separate academic units and is associated with numerous institutes and research centres, including the Walter and Eliza Hall Institute of Medical Research, Florey Institute of Neuroscience and Mental Health, the Melbourne Institute of Applied Economic and Social Research and the Grattan Institute. Amongst Melbourne’s 15 graduate schools the Melbourne Business School, the Melbourne Law School and the Melbourne Medical School are particularly well regarded.

    Four Australian prime ministers and five governors-general have graduated from Melbourne. Nine Nobel laureates have been students or faculty, the most of any Australian university.

     
  • richardmitnick 1:46 pm on September 13, 2019 Permalink | Reply
    Tags: , , , Cosmology, , ,   

    From NASA JPL-Caltech: “NASA’s WFIRST Will Help Uncover the Universe’s Fate” 

    NASA JPL Banner

    From NASA JPL-Caltech

    September 13, 2019

    Calla Cofield
    Jet Propulsion Laboratory, Pasadena, Calif.
    626-808-2469
    calla.e.cofield@jpl.nasa.gov

    Written by Ashley Balzer
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    1
    NASA WFIRST depiction. Credit: NASA’s Goddard Space Flight Center

    Scientists have discovered that a mysterious pressure dubbed “dark energy” makes up about 68% of the total energy content of the cosmos, but so far we don’t know much more about it.

    Dark Energy Survey


    Dark Energy Camera [DECam], built at FNAL


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

    Timeline of the Inflationary Universe WMAP

    The Dark Energy Survey (DES) is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013.

    According to Einstein’s theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up. To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called dark energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the DES collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.

    Exploring the nature of dark energy is one of the primary reasons NASA is building the Wide Field Infrared Survey Telescope (WFIRST), a space telescope whose measurements will help illuminate the dark energy puzzle. With a better understanding of dark energy, we will have a better sense of the past and future evolution of the universe.

    An Expanding Cosmos

    Until the 20th century, most people believed that the universe was static, remaining essentially unchanged throughout eternity. When Einstein developed his general theory of relativity in 1915, describing how gravity acts across the fabric of space-time, he was puzzled to find that the theory indicated the cosmos must either expand or contract. He made changes to preserve a static universe, adding something he called the “cosmological constant,” even though there was no evidence it actually existed. This mysterious force was supposed to counteract gravity to hold everything in place.

    However, as the 1920s were coming to a close, astronomer Georges Lemaitre, and then Edwin Hubble, made the startling discovery that with very few exceptions, galaxies are racing away from each other.

    Edwin Hubble looking through a 100-inch Hooker telescope at Mount Wilson in Southern California, 1929 discovers the Universe is Expanding

    The universe was far from static – it was ballooning outward. Consequently, if we imagine rewinding this expansion, there must have been a time when everything in the universe was almost impossibly hot and close together.

    The End of the Universe: Fire or Ice?

    The Big Bang theory describes the expansion and evolution of the universe from this initial superhot, superdense state. Scientists theorized that gravity would eventually slow and possibly even completely reverse this expansion. If the universe had enough matter in it, gravity would overcome the expansion, and the universe would collapse in a fiery “Big Crunch.”

    If not, the expansion would never end – galaxies would grow farther and farther away until they pass the edge of the observable universe. Our distant descendants might have no knowledge of the existence of other galaxies since they would be too far away to be visible. Much of modern astronomy might one day be reduced to mere legend as the universe gradually fades to an icy black.

    The Universe Isn’t Just Expanding – It’s Accelerating

    Astronomers have measured the rate of expansion by using ground-based telescopes to study relatively nearby supernova explosions. The mystery escalated in 1998 when Hubble Space Telescope observations of more distant supernovae helped show that the universe actually expanded more slowly in the past than it does today.(?) The expansion of the universe is not slowing down due to gravity, as everyone thought. It’s speeding up.

    Saul Perlmutter [The Supernova Cosmology Project] shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt and Adam Riess [The High-z Supernova Search Team] for providing evidence that the expansion of the universe is accelerating.

    Fast forward to today. While we still don’t know what exactly is causing the acceleration, it has been given a name – dark energy. This mysterious pressure remained undiscovered for so long because it is so weak that gravity overpowers it on the scale of humans, planets and even the galaxy. It is present in the room with you as you read, within your very body, but gravity counteracts it so you don’t go flying out of your seat. It is only on an intergalactic scale that dark energy becomes noticeable, acting like a sort of weak opposition to gravity.

    What Is Dark Energy?

    What exactly is dark energy? More is unknown than known, but theorists are chasing down a couple of possible explanations. Cosmic acceleration could be caused by a new energy component, which would require some adjustments to Einstein’s theory of gravity – perhaps the cosmological constant, which Einstein called his biggest blunder, is real after all.

    Alternatively, Einstein’s theory of gravity may break down on cosmological scales. If this is the case, the theory will need to be replaced with a new one that incorporates the cosmic acceleration we have observed. Theorists still don’t know what the correct explanation is, but WFIRST will help us find out.

    WFIRST Will Illuminate Dark Energy

    Previous missions have gathered some clues, but so far they haven’t yielded results that strongly favor one explanation over another. With the same resolution as Hubble’s cameras but a field of view that is 100 times larger, WFIRST will generate never-before-seen big pictures of the universe. The new mission will advance the exploration of the dark energy mystery in ways that other telescopes can’t by mapping how matter is structured and distributed throughout the cosmos, and also by measuring large numbers of distant supernovae. The results will indicate how dark energy acts across the universe, and whether and how it has changed over cosmic history.

    The mission will use three survey methods to search for an explanation of dark energy. The High Latitude Spectroscopic Survey will measure accurate distances and positions of millions of galaxies using a “standard ruler” technique. Measuring how the distribution of galaxies varies with distance will give us a window into the evolution of dark energy over time. This study will connect the galaxies’ distances with the echoes of sound waves just after the Big Bang and will test Einstein’s theory of gravity over the age of the universe.

    The High Latitude Imaging Survey will measure the shapes and distances of multitudes of galaxies and galaxy clusters. The immense gravity of massive objects warps space-time and causes more distant galaxies to appear distorted. Observing the degree of distortion allows scientists to infer the distribution of mass throughout the cosmos. This includes all of the matter we can see directly, like planets and stars, as well as dark matter – another dark cosmic mystery which is visible only through its gravitational effects on normal matter. This survey will provide an independent measurement of the growth of large-scale structure in the universe and how dark energy has affected the cosmos.

    WFIRST will also conduct a survey of one type of exploding star, building on the observations that led to the discovery of accelerated expansion. Type Ia supernovae occur when a white dwarf star explodes. Type Ia supernovae generally have the same absolute brightness at their peak, making them so-called “standard candles.” That means astronomers can determine how far away they are by seeing how bright they look from Earth – and the farther they are, the dimmer they appear. Astronomers will also look at the particular wavelengths of light coming from the supernovae to find out how fast the dying stars are moving away from us. By combining distances with brightness measurements, scientists will see how dark energy has evolved over time, providing a cross-check with the two high-latitude surveys.

    “The WFIRST mission is unique in combining these three methods. It will lead to a very robust and rich interpretation of the effects of dark energy and will allow us to make a definite statement about the nature of dark energy,” said Olivier Doré, a research scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California, and leader of the team planning the first two survey methods with WFIRST.

    Discovering how dark energy has affected the universe’s expansion in the past will shed some light on how it will influence the expansion in the future. If it continues to accelerate the universe’s expansion, we may be destined to experience a “Big Rip.” In this scenario, dark energy would eventually become dominant over the fundamental forces, causing everything that is currently bound together – galaxies, planets, people – to break apart. Exploring dark energy will allow us to investigate, and possibly even foresee, the universe’s fate.

    For more information about WFIRST, visit:

    http://www.nasa.gov/wfirst.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NASA JPL Campus

    Jet Propulsion Laboratory (JPL)) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge, on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

    Caltech Logo

    NASA image

     
  • richardmitnick 9:02 am on September 13, 2019 Permalink | Reply
    Tags: , , , Cosmology, , , New VST image of the Large Magellanic Cloud   

    From European Southern Observatory: “VISTA unveils a new image of the Large Magellanic Cloud” 

    ESO 50 Large

    From European Southern Observatory

    13 September 2019
    Maria-Rosa Cioni
    Leibniz-Institut für Astrophysik Potsdam (AIP)
    Potsdam, Germany
    Tel: +49 331 7499 651
    Email: mcioni@aip.de

    Mariya Lyubenova
    ESO Head of Media Relations
    Garching bei München, Germany
    Tel: +49 89 3200 6188
    Email: pio@eso.org

    1
    The Large Magellanic Cloud revealed by VISTA


    ESOcast 206 Light: VISTA Unveils the Large Magellanic Cloud (4K UHD)


    Zooming on the Large Magellanic Cloud


    Comparison of the Large Magellanic Cloud in infrared and visible light


    Comparison of the Tarantula nebula in infrared and visible light

    The Large Magellanic Cloud, or LMC, is one of our nearest galactic neighbors, at only 163 000 light years from Earth. With its sibling the Small Magellanic Cloud, these are among the nearest dwarf satellite galaxies to the Milky Way. The LMC is also the home of various stellar conglomerates and is an ideal laboratory for astronomers to study the processes that shape galaxies.

    ESO’s VISTA telescope [below], has been observing these two galaxies for the last decade. The image presented today is the result of one of the many surveys that astronomers have performed with this telescope. The main goal of the VISTA Magellanic Clouds (VMC) Survey has been to map the star formation history of the Large and Small Magellanic Clouds, as well as their three-dimensional structures.

    VISTA was key to this image because it observes the sky in near-infrared wavelengths of light. This allows it to see through clouds of dust that obscure parts of the galaxy. These clouds block a large portion of visible light but are transparent at the longer wavelengths VISTA was built to observe. As a result, many more of the individual stars populating the centre of the galaxy are clearly visible. Astronomers analysed about 10 million individual stars in the Large Magellanic Cloud in detail and determined their ages using cutting-edge stellar models[1]. They found that younger stars trace multiple spiral arms in this galaxy.

    For millennia, the Magellanic Clouds have fascinated people in the Southern Hemisphere, but they were largely unknown to Europeans until the Age of Discovery. The name we use today harkens back to the explorer Ferdinand Magellan, who 500 years ago began the first circumnavigation of the Earth. The records the expedition brought back to Europe revealed many places and things to Europeans for the first time. The spirit of exploration and discovery is ever more live today in the work of astronomers around the world, including the VMC Survey team whose observations led to this stunning image of the LMC.
    Notes

    [1] Stellar models allow astronomers to predict the life and death of stars, providing insights into properties like their ages, mass, and temperature.

    More information

    The stars revealed by this image were discussed in the paper “The VMC Survey – XXXIV. Morphology of Stellar Populations in the Magellanic Clouds” to appear in the journal Monthly Notices of the Royal Astronomical Society.

    See the full article here .


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    Please help promote STEM in your local schools.


    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 EEuropean Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO/HARPS at La Silla

    ESO 3.6m telescope & HARPS at Cerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    MPG/ESO 2.2 meter telescope at Cerro La Silla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres

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

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

    2009 ESO VLTI Interferometer image, Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).

    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres

    ESO VLT Survey telescope

    Part of ESO’s Paranal Observatory, the VISTA Telescope observes the brilliantly clear skies above the Atacama Desert of Chile. Credit: ESO/Y. Beletsky, with an elevation of 2,635 metres (8,645 ft) above sea level

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

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

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

     
  • richardmitnick 2:05 pm on September 12, 2019 Permalink | Reply
    Tags: A star called S0-2 [Andrea Ghez' UCLA Galactic Center Group pet star], , , , , Cosmology,   

    From UCLA Newsroom: “Black hole at the center of our galaxy appears to be getting hungrier” 


    From UCLA Newsroom

    September 11, 2019
    Stuart Wolpert
    UCLA
    310-206-0511
    swolpert@stratcomm.ucla.edu

    UCLA astronomers notice brightest light in 24 years of observations.

    1
    Rendering of a star called S0-2 [Andrea Ghez’, UCLA Galactic Center Group, pet star] orbiting the supermassive black hole at the center of the Milky Way. It did not fall in, but its close approach could be one reason for the black hole’s growing appetite. Nicolle Fuller/National Science Foundation.

    Star S0-2 Andrea Ghez Keck/UCLA Galactic Center Group at SGR A*, the supermassive black hole at the center of the milky way

    The enormous black hole at the center of our galaxy is having an unusually large meal of interstellar gas and dust, and researchers don’t yet understand why.

    “We have never seen anything like this in the 24 years we have studied the supermassive black hole,” said Andrea Ghez, UCLA professor of physics and astronomy and a co-senior author of the research. “It’s usually a pretty quiet, wimpy black hole on a diet. We don’t know what is driving this big feast.”

    A paper about the study, led by the UCLA Galactic Center Group, which Ghez heads, is published today in Astrophysical Journal Letters.

    The researchers analyzed more than 13,000 observations of the black hole from 133 nights since 2003. The images were gathered by the W.M. Keck Observatory in Hawaii and the European Southern Observatory’s Very Large Telescope in Chile.

    Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

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

    The team found that on May 13, the area just outside the black hole’s “point of no return” (so called because once matter enters, it can never escape) was twice as bright as the next-brightest observation.

    They also observed large changes on two other nights this year; all three of those changes were “unprecedented,” Ghez said.

    The brightness the scientists observed is caused by radiation from gas and dust falling into the black hole; the findings prompted them to ask whether this was an extraordinary singular event or a precursor to significantly increased activity.

    “The big question is whether the black hole is entering a new phase — for example if the spigot has been turned up and the rate of gas falling down the black hole ‘drain’ has increased for an extended period — or whether we have just seen the fireworks from a few unusual blobs of gas falling in,” said Mark Morris, UCLA professor of physics and astronomy and the paper’s co-senior author.

    The team has continued to observe the area and will try to settle that question based on what they see from new images.

    “We want to know how black holes grow and affect the evolution of galaxies and the universe,” said Ghez, UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics. “We want to know why the supermassive hole gets brighter and how it gets brighter.”

    The new findings are based on observations of the black hole — which is called Sagittarius A*, or Sgr A* — during four nights in April and May at the Keck Observatory. The brightness surrounding the black hole always varies somewhat, but the scientists were stunned by the extreme variations in brightness during that timeframe, including their observations on May 13.

    “The first image I saw that night, the black hole was so bright I initially mistook it for the star S0-2, because I had never seen Sagittarius A* that bright,” said UCLA research scientist Tuan Do, the study’s lead author. “But it quickly became clear the source had to be the black hole, which was really exciting.”

    One hypothesis about the increased activity is that when a star called S0-2 made its closest approach to the black hole during the summer 2018, it launched a large quantity of gas that reached the black hole this year.

    Another possibility involves a bizarre object known as G2, which is most likely a pair of binary stars, which made its closest approach to the black hole in 2014. It’s possible the black hole could have stripped off the outer layer of G2, Ghez said, which could help explain the increased brightness just outside the black hole.

    Morris said another possibility is that the brightening corresponds to the demise of large asteroids that have been drawn in to the black hole.

    No danger to Earth

    The black hole is some 26,000 light-years away and poses no danger to our planet. Do said the radiation would have to be 10 billion times as bright as what the astronomers detected to affect life on Earth.

    Astrophysical Journal Letters also published a second article by the researchers, describing speckle holography, the technique that enabled them to extract and use very faint information from 24 years of data they recorded from near the black hole.

    Ghez’s research team reported July 25 in the journal Science the most comprehensive test of Einstein’s iconic general theory of relativity near the black hole. Their conclusion that Einstein’s theory passed the test and is correct, at least for now, was based on their study of S0-2 as it made a complete orbit around the black hole.

    Ghez’s team studies more than 3,000 stars that orbit the supermassive black hole. Since 2004, the scientists have used a powerful technology that Ghez helped pioneer, called adaptive optics, which corrects the distorting effects of the Earth’s atmosphere in real time.

    Keck Adaptive Optics

    But speckle holography enabled the researchers to improve the data from the decade before adaptive optics came into play. Reanalyzing data from those years helped the team conclude that they had not seen that level of brightness near the black hole in 24 years.

    “It was like doing LASIK surgery on our early images,” Ghez said. “We collected the data to answer one question and serendipitously unveiled other exciting scientific discoveries that we didn’t anticipate.”

    Co-authors include Gunther Witzel, a former UCLA research scientist currently at Germany’s Max Planck Institute for Radio Astronomy; Mark Morris, UCLA professor of physics and astronomy; Eric Becklin, UCLA professor emeritus of physics and astronomy; Rainer Schoedel, a researcher at Spain’s Instituto de Astrofısica de Andalucıa; and UCLA graduate students Zhuo Chen and Abhimat Gautam.

    The research is funded by the National Science Foundation, W.M. Keck Foundation, the Gordon and Betty Moore Foundation, the Heising-Simons Foundation, Lauren Leichtman and Arthur Levine, and Howard and Astrid Preston.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
  • richardmitnick 10:45 am on September 12, 2019 Permalink | Reply
    Tags: "Hubble Reveals Latest Portrait of Saturn", , , , Cosmology,   

    From NASA/ESA Hubble Telescope: “Hubble Reveals Latest Portrait of Saturn” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope


    From NASA/ESA Hubble Telescope

    12 September 2019
    Bethany Downer
    ESA/Hubble, Public Information Officer
    Garching, Germany
    Email: Bethany.Downer@partner.eso.org

    Donna Weaver
    Space Telescope Science Institute, Baltimore, Maryland
    410-338-4493
    dweaver@stsci.edu

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

    Amy Simon
    Goddard Space Flight Center, Greenbelt, Maryland
    amy.simon@nasa.gov

    Mike Wong
    University of California, Berkeley, California
    mikewong@astro.berkeley.edu

    2
    The NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 observed Saturn on 20 June 2019 as the planet made its closest approach to Earth this year, at approximately 1.36 billion kilometres away.

    NASA/ESA Hubble WFC3

    Saturn is so beautiful that astronomers cannot resist using the Hubble Space Telescope to take yearly snapshots of the ringed world when it is at its closest distance to Earth. These images, however, are more than just beauty shots. They reveal a planet with a turbulent, dynamic atmosphere. This year’s Hubble offering, for example, shows that a large storm visible in the 2018 Hubble image in the north polar region has vanished. Smaller storms pop into view like popcorn kernels popping in a microwave oven before disappearing just as quickly. Even the planet’s banded structure reveals subtle changes in color. But the latest image shows plenty that hasn’t changed. The mysterious six-sided pattern, called the “hexagon,” still exists on the north pole. Caused by a high-speed jet stream, the hexagon was first discovered in 1981 by NASA’s
    Voyager 1 spacecraft.

    NASA/Voyager 1

    Saturn’s signature rings are still as stunning as ever. The image reveals that the ring system is tilted toward Earth, giving viewers a magnificent look at the bright, icy structure. Hubble resolves numerous ringlets and the fainter inner rings. This image reveals an unprecedented clarity only seen previously in snapshots taken by NASA spacecraft visiting the distant planet. Astronomers will continue their yearly monitoring of the planet to track shifting weather patterns and identify other changes. The second in the yearly series, this image is part of the Outer Planets Atmospheres Legacy (OPAL) project. OPAL is helping scientists understand the atmospheric dynamics and evolution of our solar system’s gas giant planets.

    1
    A. Simon (Goddard Space Flight Center), M.H. Wong (University of California, Berkeley), and the OPAL Team

    Since the Hubble Space Telescope was launched, its goal has been to study not only distant astronomical objects, but also the planets within our Solar System. Hubble’s high-resolution images of our planetary neighbours can only be surpassed by pictures taken from spacecraft that actually visit these bodies. However, Hubble has one advantage over space probes; it can look at these objects periodically and observe them over much longer periods than any passing probe could.

    Saturn hosts many recognisable features, most notably its trademark ring system, which is now tilted towards Earth. This gives us a magnificent view of its bright icy structure. Hubble resolves numerous ringlets and the fainter inner rings. Dutch astronomer Christiaan Huygens first identified the rings in 1655 and thought they were a continuous disk encircling the planet, but we now know them to be composed of orbiting particles of ice and dust. Though all of the gas giants boast rings, Saturn’s are the largest and most spectacular.

    The age of Saturn’s ring system continues to be debated. And, even more perplexingly, it’s unknown what cosmic event formed the rings. There is no consensus among planetary astronomers today.

    Another intriguing feature is the long-lasting hexagon-shaped structure circling the planet’s north pole. It is a mysterious six-sided pattern caused by a high-speed jetstream. The hexagon is so large that four Earths could fit inside its boundaries (there is no similar structure at Saturn’s south pole).

    Other features, however, are not as long-lasting. A large storm in the north polar region spotted by Hubble last year has disappeared. Smaller, convective storms, such as the one just above the centre of the planet’s image, also come and go.

    Saturn’s amber colours come from summer smog-like hazes, produced in photochemical reactions driven by solar ultraviolet radiation. Below the haze lie clouds of ammonia ice crystals, as well as deeper, unseen lower-level clouds of ammonium hydrosulphide and water. The planet’s banded structure is caused by the winds and clouds at different altitudes.

    Saturn’s appearance changes with its seasons, caused by the planet’s 27-degree axial tilt. This image was taken during summer in the planet’s northern hemisphere.

    This image is the second in a yearly series of snapshots taken as part of the Outer Planets Atmospheres Legacy (OPAL) project. OPAL is helping scientists to understand the atmospheric dynamics and evolution of our Solar System’s gas giant planets. In Saturn’s case, astronomers will be able to track shifting weather patterns and other changes to identify trends.

    See the full article here .


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    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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    AURA Icon

     
  • richardmitnick 10:18 am on September 12, 2019 Permalink | Reply
    Tags: "A 2nd mysterious object from interstellar space may be about to fly through our solar system", , , , , , Cosmology, Object C/2019 Q4   

    From Business Insider: “A 2nd mysterious object from interstellar space may be about to fly through our solar system” 

    From Business Insider

    9.11.19
    Dave Mosher
    Morgan McFall-Johnsen

    1
    Astronomers think object C/2019 Q4 (the green line) could be an interstellar object, perhaps a comet from another star system. OrbitalSimulator.com

    Astronomers think they’ve detected an interstellar object approaching our solar system.

    Called “C/2019 Q4” (formerly “gb00234”), the object appears to be following a path originating from outside the solar system. It may pass near Mars in October.

    This would be only the second interstellar object ever observed in our solar system. The first such visitor, ‘Oumuamua, took scientists by surprise in 2017. This time, they’re getting ready to watch C/2019 Q4 with “everything” they can, one astronomer said.

    If C/2019 Q4 is indeed interstellar, scientists should be able to study the object until it grows too dim to see, in early 2021.

    Astronomers may have spotted the second object ever to visit our solar system from another star system. The object may even fly near Mars in October.

    The scientists’ hunch is strong yet not entirely certain. But right now, the chances are much higher that the object, known as comet “C/2019 Q4 (Borisov)” (or “gb00234”), is interstellar, rather than a rock from within the solar system.

    The first such interstellar object ever detected, the mysterious and cigar-shaped ‘Oumuamua (which a few scientists controversially argued may be alien in origin), zoomed through our solar system in 2017.

    ‘Oumuamua

    An amateur astronomer in Ukraine, Gennady Borisov, may have been the first to spot C/2019 Q4 in the sky on August 30. It hasn’t yet entered our solar system, but astronomers have been collecting data in hopes of plotting the object’s path through space and figuring out where it came from.

    “It’s so exciting, we’re basically looking away from all of our other projects right now,” Olivier Hainaut, an astronomer with the European Southern Observatory, told Business Insider on Wednesday.

    Hainaut was part of a global team of astronomers that studied ‘Oumuamua as it passed through the solar system two years ago.

    “The main difference from ‘Oumuamua and this one is that we got it a long, long time in advance, ” he added. “Now astronomers are much more prepared.”

    Early images suggest C/2019 Q4 is followed by a small tail or halo of dust. That’s a distinct trait of comets — they hold ice that gets heated up by nearby stars, leading them to shoot out gas and grit into space. The dust could make C/2019 Q4 simpler to track than ‘Oumuamua, since dust brightly reflects sunlight.

    This could also make it easier for scientists to study the object’s composition, since telescope instruments can “taste” light to look for chemical signatures.

    “Here we have something that was born around another star and traveling toward us,” Hainaut said. “It’s the next best thing to sending a probe to a different solar system.”

    Astronomers are preparing to watch the object with as many telescopes as possible.

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

    Astronomers around the globe are grabbing every telescope available to plot C/2019 Q4’s path through space. The goal: see whether the object has an orbit that’s elliptical (oval-shaped and around the sun) or hyperbolic (checkmark-shaped, and on an open-ended trajectory).

    It seems much more likely that its path is hyperbolic, though astronomers say more observations are required to know for sure. In particular, they’re trying to ascertain C/2019 Q4’s eccentricity, or how extreme its orbit is.

    “The error indicates it’s still possible that’s within the solar system,” Hainaut said. “But that error is decreasing as we get more and more data, and the eccentricity is looking interstellar.”

    The object’s seemingly high velocity and comet-like shroud of dust also tilt the scales toward interstellar, Hainaut added.

    3
    This rough simulation shows C/2019 Q4’s possible orbital path (green) through the solar system. It may pass between the orbits of Jupiter (purple) and Mars (orange) in late October.http://www.OrbitalSimulator.com

    “It could be a few days or a few weeks before we have enough data to definitively say. But even with the very best data, we may need more,” he said. “It’s frustrating.”

    When ‘Oumuamua sped past Earth at a distance of just 15 million miles in October 2017, astronomers had no idea it was coming.

    “We had to scramble for telescope time,” Hainaut said. “This time, we’re ready.”

    If it’s interstellar, C/2019 Q4 would reach its closest point to the sun at the end of December, and scientists should be able to observe it through about January 2021.

    Hainaut and his colleagues have some smaller telescopes queued up for observations, but he said he’d like to use “everything” to observe C/2019 Q4. His team is trying to get time on the “big guys,” including the Very Large Telescope in Chile, the Keck Observatory, and the Gemini telescope in Hawaii.


    NOAO Gemini North on MaunaKea, Hawaii, USA, Altitude 4,213 m (13,822 ft)

    Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

    He said a colleague and likely other astronomers around the globe were also working on proposals to have the Hubble Space Telescope take a look. Others are seeking to use NASA’s two infrared space telescopes: Spitzer, and the Wide-field Infrared Survey Explorer.

    NASA/ESA Hubble Telescope

    NASA/Spitzer Infrared Telescope

    NASA/WISE Telescope

    But scientists remain cautious about C/2019 Q4’s identity.

    6
    An artist’s depiction of the interstellar object ‘Oumuamua.ESA/Hubble; NASA; ESO; M. Kornmesser

    Though many astronomers are excited about C/2019 Q4, more work has to be done to confirm it as interstellar.

    “This is not the first object since 2017/1I, better known as ‘Oumuamua, to show a hyperbolic orbit,” Michele Bannister, a planetary astronomer at Queen’s University Belfast, tweeted on Wednesday.

    Bannister noted that with such limited observations, an object could appear to have a rare interstellar orbit but later turn out to have an orbit within our solar system.

    “Sometimes, we just have to wait for the motion of the heavens. And make…more observations,” she added.

    Currently, those observations aren’t easy to get, Hainaut said. C/2019 Q4 is positioned close to the sun, placing it close to Earth’s horizon and giving astronomers a very limited window of time before dawn to study it.

    “It’s hard to see, but we have the best guys doing astrometry, trying to measure its position in the sky,” he said. “It could be a few days or a few weeks before we have enough data to definitively say.”

    If C/2019 Q4 does turn out to be a second interstellar object, that would bode well for a mission Hainaut is proposing to send robotic probes into space to intercept future objects like this.

    “One of the main issues is: How many of these are there? If we detect one every century, it’s hard to plan a mission to intercept one,” he said.

    On the other hand, if these objects come every couple of years, astronomers might even be able to get choosy about which object to intercept.

    “This suggests we can afford to wait one or two or three years to get the right one, and maybe not the first one we spot after organizing a mission,” Hainaut said.

    See the full article here .

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  • richardmitnick 8:12 am on September 12, 2019 Permalink | Reply
    Tags: , , , Cave training- to explore uncharted terrains on the Moon and Mars, Cosmology, , Futuristic Geology   

    From European Space Agency: “A new journey into Earth for space exploration” 

    ESA Space For Europe Banner

    From European Space Agency

    11 September 2019

    Six astronauts, five space agencies and a fresh start into underground worlds to help prepare for living on other planets. ESA’s latest training adventure will equip an international crew with skills to explore uncharted terrains on the Moon and Mars, this time with a focus on the search for water.

    The CAVES training course takes astronauts to the depths of Earth to improve their communication, problem-solving and teamwork skills.

    After a week of preparations above and underground, the ‘cavenauts’ are set to explore a cave in Slovenia where they will live and work for six days.

    “It is all part of a simulation, but the experience is the closest you can get on this planet to the environmental, psychological and logistics constraints of a space mission,” explains course designer Loredana Bessone.

    “It is all part of a simulation, but the experience is the closest you can get on this planet to the environmental, psychological and logistics constraints of a space mission,” explains course designer Loredana Bessone.

    1
    CAVES
    27/06/2016 3:19 pm
    Copyright ESA–V. Crobu

    Astronauts squeeze through a tight spot during ESA’s underground astronaut training course CAVES, June 2016. CAVES stands for Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills. The two-week course prepares astronauts to work safely and effectively in multicultural teams in an environment where safety is critical – in caves. After a week of surface training, the astronauts descend into the caves to set up basecamp 800 m underground. The similarities between caving and spaceflight are highlighted throughout the course. Speleologists and astronauts adopt the ‘buddy system’, and both astronaut trainers and CAVES instructors repeat the same mantras of “slow is fast,” “check your gear, and then trust it,” and “always be aware of where you are and where your buddy is.”

    “The training involves real science, real operations and real astronauts with the best speleologists in the field,” she adds.

    The six cavenauts of this edition of CAVES are ESA astronaut Alexander Gerst, NASA astronauts Joe Acaba and Jeanette Epps, Roscosmos’ cosmonaut Nikolai Chub, Canadian Space Agency astronaut Josh Kutryk and JAXA’s Takuya Onishi.

    “This new space-caving adventure helps them to learn from each other, from themselves and from the cave, which always humbles you with its enclosing spaces and darkness,” says CAVES technical course director Francesco Sauro.

    The training starts today, and the cavenauts will begin their descent into the dark to set up a base camp on 20 September.

    Supported by a team of instructors and safety personnel, the six explorers will take their own decisions and work autonomously, isolated from the outside world and coping with communication delays.

    Follow the water

    Underground exploration means following air and water flows as telltale signals of new paths ahead. The crew will learn how to trace water – the main link with life on Earth and a precious resource in space exploration.

    3
    Astronauts from five space agencies around the world took part in ESA’s CAVES training course– Cooperative Adventure for Valuing and Exercising human behaviour and performance Skills. The two-week course prepares astronauts to work safely and effectively in multicultural teams in an environment where safety is critical. As they explore the caves of Sardinia they encountered caverns, underground lakes and strange microscopic life. They tested new technology and conducted science – just as if they were living on the International Space Station. The six astronauts relied on their own skills, teamwork and ground control to achieve their mission goals – the course is designed to foster effective communication, decision-making, problem-solving, leadership and team dynamics. 2016 was the first international space cooperation to involve astronauts from China, Russia, Japan, ESA and America, with cosmonaut Sergei Vladimirovich, ESA astronaut Pedro Duque, taikonaut Ye Guangfu, Japanese astronaut Aki Hoshide and NASA astronauts Ricky Arnold and Jessica Muir taking part.The ‘cavenauts’ said goodbye to sunlight and spent six nights underground, setting up basecamp in the Sa Grutta cave in Sardinia, Italy. This picture was taken on day five underground. Follow CAVES via twitter @ESA_CAVES or with #CAVES2016 or on the CAVES blog.

    Caves are normally made by running waters. ESA picked a cave for this edition in an area where rivers flow underground. To keep the element of exploration, astronauts themselves do not know the exact location.

    This entrance to the underground is called ‘Lepa Jama’ – meaning ‘Beautiful Cave’ in Slovenian. “The cave is a labyrinth of passages mostly unexplored and rich in indigenous species,” says Francesco.

    “This Karst area is one of Europe’s natural wonders and where speleology was actually born,” says Franci Gabrovšek, professor at the Karst Research Institute ZRC SAZU in Slovenia.

    “The genesis of caves, mysterious groundwater flow and subterranean life still pose numerous scientific questions. Astronauts could help us answer them,” adds Franci.

    What lies beneath – science and technology

    Inhospitable and hard to access, caves are almost untouched worlds and ideal traps for scientific evidence. Astronauts will carry out a dozen of experiments and will be on the lookout for signs of life that have adapted to the extremes.

    “We are really hoping to find new species again,” says Loredana recalling the discovery of the crustacean Alpioniscus Sideralis during the second CAVES edition in 2012.

    4
    Alpioniscus species

    Monitoring the presence of ‘microplastics’ will be part of the science programme. These millimetric plastics can end up in the food chain and raise concerns for the environment and human health.

    The astronauts will use with an upgraded version of the Electronic Field Book. This all-in-one, easy-to-use platform will allow them to deliver science and video logs while checking procedures and cue cards on a tablet.

    Above the ground, mission control will track their progress with a 3D map generated on the app as they explore the cave. Scientists can locate the astronauts’ scientific observations paired with pictures, and send their comments back to the cave.

    “It is augmented science. This technology saves crew and ground teams time and helps improve the scientific return of the mission,” says Loredana.

    As all space agencies prepare for Moon exploration, “ESA is taking the lead in subsurface expeditions to shape future missions exploring lunar caves,” she assures. Ideas on how to detect, map and explore caves on the Moon are welcome.

    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 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.

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