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  • richardmitnick 6:55 am on September 24, 2017 Permalink | Reply
    Tags: , , , Black Hole Sculpts an Hourglass Galaxy, Cosmology, NASA on tumblr   

    From NASA: “NASA on Tumblr – Black Hole Sculpts an Hourglass Galaxy” 

    NASA image
    NASA

    Black Hole Sculpts an Hourglass Galaxy

    When it comes to galaxies, our home, the Milky Way, is rather neat and orderly. Other galaxies can be much more chaotic. For example, the Markarian 573 galaxy has a black hole at its center which is spewing beams of light in opposite directions, giving its inner regions more of an hourglass shape.

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    Our scientists have long been fascinated by this unusual structure, seen above in optical light from the Hubble Space Telescope. Now their search has taken them deeper than ever — all the way into the super-sized black hole at the center of one galaxy.

    So, what do we think is going on? When the black hole gobbles up matter, it releases a form of high-energy light called radiation (particularly in the form of X-rays), causing abnormal patterns in the flow of gas.

    Let’s take a closer look.

    Meet Markarian 573, the galaxy at the center of this image from the Sloan Digital Sky Survey, located about 240 million light-years away from Earth in the constellation Cetus. It’s the galaxy’s odd structure and the unusual motions of its components that inspire our scientists to study it.

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    SDSS Telescope at Apache Point Observatory, NM, USA

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    As is the case with other so-called active galaxies, the ginormous black hole at the center of Markarian 573 likes to eat stuff. A thick ring of dust and gas accumulates around it, forming a doughnut. This ring only permits light to escape the black hole in two cone-shaped regions within the flat plane of the galaxy — and that’s what creates the hourglass, as shown in the illustration above.

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    Zooming out, we can see the two cones of emission (shown in gold in the animation above) spill into the galaxy’s spiral arms (blue). As the galaxy rotates, gas clouds in the arms sweep through this radiation, which makes them light up so our scientists can track their movements from Earth.

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    What happens next depends on how close the gas is to the black hole. Gas that’s about 2,500 light-years from the black hole picks up speed and streams outward (shown as darker red and blue arrows). Gas that’s farther from the black hole also becomes ionized, but is not driven away and continues its motion around the galaxy as before.

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    Here is an actual snapshot of the inner region of Markarian 573, combining X-ray data (blue) from our Chandra X-ray Observatory and radio observations (purple) from the Karl G. Jansky Very Large Array in New Mexico with a visible light image (gold) from our Hubble Space Telescope. Given its strange appearance, we’re left to wonder: what other funky shapes might far-off galaxies take?

    For more information about the bizarre structure of Markarian 573, visit http://svs.gsfc.nasa.gov/12657

    See the full article here .

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    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

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  • richardmitnick 4:41 pm on September 22, 2017 Permalink | Reply
    Tags: , , , , Cosmology, When a Star and a Binary Meet   

    From AAS NOVA: ” When a Star and a Binary Meet” 

    AASNOVA

    American Astronomical Society

    22 September 2017
    Susanna Kohler

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    What happens when stars interact in dense environments, such as globular clusters like the one pictured here? [HST/NASA/ESA]

    What happens in the extreme environments of globular clusters when a star and a binary system meet? A team of scientists has new ideas about how these objects can deform, change their paths, spiral around each other, and merge.

    Getting to Know Your Neighbors

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    Two simulations of the interaction of a white-dwarf–compact-object binary with a single incoming compact object (progressing from left to right). When tides are not included (bottom panel), the system interacts chaotically for a while before the single compact object is ejected and the binary system leaves on slightly modified orbit. When tides are included (top panel), the chaotic interactions eventually result in the tidal inspiral and merger of the binary (labeled in the top diagram and shown in detail in the inset). [Samsing et al. 2017]

    Stars living in dense environments, like globular clusters, experience very different lives than those in the solar neighborhood. In these extreme environments, close encounters are the norm — and this can lead to a variety of interesting interactions between the stars and systems of stars that encounter each other.

    One common type of meeting is that of a single star with a binary star system. Studies of such interactions often treat all three bodies like point sources, examining outcomes like:

    1. All three objects are mutually unbound by the interaction, resulting in three single objects.
    2. A flyby encounter occurs, in which the binary survives the encounter but its orbit becomes modified by the third star.
    3. An exchange occurs, in which the single star swaps spots with one of the binary stars and ejects it from the system.

    Complexities of Extended Objects

    But what if you treat the bodies not like point sources, but like extended objects with actual radii (as is true in real life)? Then there are additional complexities, such as collisions when the stars’ radii overlap, general relativistic effects when the stars pass very near one another, and tidal oscillations as gravitational forces stretch the stars out during a close passage and then release afterward.

    In a recently published study led by Johan Samsing (an Einstein Fellow at Princeton University), the authors explore how these complexities change the behavior of binary-single interactions in the centers of dense star clusters.

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    One example — again in the case of a white-dwarf–compact-object binary interacting with a single compact object — of the cross sections for different types of interactions. Exchanges (triangles) are generally most common, and direct collisions (circles) occur frequently, but tidal inspirals (pluses) can occur with similar frequency in such systems. Inspirals due to energy loss to gravitational waves (crosses) can occur as well. [Samsing et al. 2017]

    How Tides Change Things

    Using numerical simulations with an N-body code, and following up with analytic arguments, Samsing and collaborators show that the biggest change when they include effects such as tides is a new outcome that sometimes results from the chaotic evolution of the triple interaction: tidal inspirals.

    Tidal inspirals occur when a close passage creates tidal oscillations in a star, draining energy from the binary orbit. Under the right conditions, the loss of energy will lead to the stars’ inspiral, eventually resulting in a merger. This new channel for mergers — similar to mergers due to energy lost to gravitational waves — can occur even more frequently than collisions in some systems.

    Samsing and collaborators demonstrate that tidal inspirals occur more commonly for widely separated binaries and small-radius objects. Highly eccentric white-dwarf–neutron-star mergers, for example, can be dominated by tidal inspirals.

    The authors point out that this interesting population of eccentric compact binaries likely results in unique electromagnetic and gravitational-wave signatures — which suggests that further studies of these systems are important for better understanding what we can expect to observe when stars encounter each other in dense stellar systems.
    Citation

    Johan Samsing et al 2017 ApJ 846 36. doi:10.3847/1538-4357/aa7e32

    Related Journal Articles
    Further references at the full article with links.

    See the full article here .

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    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 1:09 pm on September 22, 2017 Permalink | Reply
    Tags: , , , BLNR-Board of Land and Natural Resources, Cosmology, Process to secure a Conservation District Use Permit (CDUP) to build TMT on Maunakea continued,   

    From TMT: “Hawaii Board of Land & Natural Resources Hears Final Arguments in Conservation District Use Permit Contested Case” 

    Thirty Meter Telescope Banner

    Thirty Meter Telescope
    Thirty Meter Telescope

    09.21.2017
    Press Release

    [Hilo, HI – Sep. 20, 2017] The process to secure a Conservation District Use Permit (CDUP) to build TMT on Maunakea continued in Hawaii, as the state land board – also known as the Board of Land and Natural Resources (BLNR) – heard final oral arguments from all parties involved in the contested case.

    The hearing at the Grand Naniloa Hotel in Hilo on Hawaii Island allowed the Board to listen to both sides of the debate on whether Board members should issue a CDUP to the University of Hawaii – Hilo to allow construction of the Thirty Meter Telescope on Maunakea.

    After nearly five months of evidentiary hearings that ran from October 2016 to March 2017, contested case Hearings Officer and former Judge Riki May Amano released a 305-page report recommending the state land board issue the CDUP. As required by law, today’s hearing afforded the seven-member state land board the opportunity to hear directly from the 23 participating contested case parties before deciding on the permit.

    The proceedings were open to the public. Each of the 23 parties involved were given 15 minutes to make their case on whether the CDUP should be issued or rejected.

    The three parties in support of TMT – University of Hawaii at Hilo, TMT International Observatory, and the Native Hawaiian group PUEO (Perpetuating Unique Educational Opportunities) – were first to give their oral arguments, followed by the project opponents. Oral arguments were followed by rebuttals, along with follow-up questions by the state land board.

    BLNR will now review and take into consideration all of the arguments, as well as Judge Amano’s report before making their final decision on the CDUP.

    Following the hearing, TMT International Observatory Executive Director Ed Stone said:

    “This is an important day for TMT with the conclusion of the second contested case related to the Conservation District Use Permit needed for TMT to be built on Maunakea. We deeply appreciate the time and attention given by both the Board of Land & Natural Resources and Judge Riki May Amano in considering whether a state permit should be granted.

    “Everyone had the opportunity to be heard as part of the process, and we are hopeful that the Board will act quickly on its decision and that it will be a positive one for TMT. We thank all of our supporters and friends who have been with us during the hearing process over the past 10 years.”

    Background:

    All University of Hawaii-managed lands on Maunakea, including the site for TMT, are in a conservation district, which requires a Conservation District Use Permit approved by the BLNR. In April 2013, following a contested case hearing that took seven days over the course of two months, the BLNR issued a CDUP to the University of Hawaii at Hilo for the construction of TMT on Maunakea.

    In late 2015, the Hawaii Supreme Court invalidated the permit stating that at the time the permit was initially granted, a contested case hearing was also approved, as was a stay on construction pending the outcome of the contested case hearing. The Supreme Court returned the case to the Hawaii Circuit Court and instructed that a new contested case hearing be conducted before the Board.

    That second contested case got underway in October 2016. Following 44 days of testimony by 71 witnesses over five months, that hearing concluded in early March 2017.

    Over the last 10 years, TMT has followed the state’s laws, procedures and processes in its efforts to build TMT on Maunakea. More than 20 public hearings have been held since 2008. An EIS was completed and approved. For the complete process, visit http//www.maunakeaandtmt.org.

    What’s Next:

    The BLNR will review all evidence and issue its decision. An exact timeframe is not known.

    TMT is also awaiting resolution on the state’s consent to the University of Hawaii’s sublease to the TMT International Observatory.

    See the full article here .

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    Near the center of Pasadena, California, a team of scientists, engineers, and project specialists is busily planning and designing what eventually will become the most advanced and powerful optical telescope on Earth. When completed later this decade, the Thirty Meter Telescope (TMT) will enable astronomers to study objects in our own solar system and stars throughout our Milky Way and its neighboring galaxies, and forming galaxies at the very edge of the observable Universe, near the beginning of time.
    Partners
    The Association of Canadian Universities for Research in Astronomy
    California Institute of Technology
    Department of Science and Technology of India
    The National Astronomical Observatories, Chinese Academy of Sciences (NAOC)
    National Astronomical Observatory of Japan
    University of California

     
  • richardmitnick 7:47 am on September 22, 2017 Permalink | Reply
    Tags: , , , , Cosmology, , From stars to galaxies   

    From ESA: “From stars to galaxies”, ESA/Herschel 

    ESA Space For Europe Banner

    European Space Agency

    9.22.17

    Explore stellar nurseries in our Milky Way and other galaxies as viewed through the infrared eye of the Herschel space observatory.

    ESA/Herschel spacecraft

    Herschel’s view of new stars and molecular clouds

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    Credits: ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech), CC BY-SA 3.0 IGO

    The bubbles and wisps portrayed in this image by ESA’s Herschel observatory reveal great turmoil in the W3/W4/W5 complex of molecular clouds and star-forming regions. Located over 6000 light-years away, in the northern constellation Cassiopeia, it is one of the best regions in which to study the life and death of massive stars in our Milky Way galaxy.

    Observing the sky at far-infrared and submillimetre wavelengths from 2009 to 2013, Herschel could catch the faint glow of dust grains interspersed in these clouds. Astronomers can use this glow to trace the otherwise dark gas where star formation unfolds.

    The three regions that make up the complex – W3, W4 and W5 – owe their name to astronomer Gart Westerhout, who identified them in the 1950s as the third, fourth and fifth sources of his survey of the Galaxy at radio wavelengths.

    The bright, white region towards the top right of the image, hosting three brilliant spots, is W3, a giant molecular cloud containing one of the most active factories of massive stars in the outer Milky Way. For its star-making activity, the cloud draws from a total reservoir of raw material equivalent to several hundred thousand times the mass of our Sun.

    The large, blue-greenish cavity to the lower left of W3 is W4, a bubble carved by winds and supernova explosions of the massive stars in IC1805, the star-forming region at its core.

    The other large cavity, on the left side of the image, is W5, consisting of two adjacent bubbles powered by intense winds and explosions of the massive stars that are coming to life in several stellar nurseries nestled within this region.

    Many seeds of new stars in this complex, especially in W3 and W5, have been observed along pillars, edges and other features that are being sculpted in the cloud material by the mighty effects of nearby massive stars. This suggests that each generation of stars is triggering the formation of the next one.

    While these regions are prime locations to study the poorly understood processes that lead to the formation of massive stars, they also host large amounts of young, low-mass stars, providing astronomers with an extraordinary laboratory to investigate the full complexity of star formation in the Milky Way.

    This two-colour image combines Herschel observations at 70 microns (cyan) and 100 microns (orange), and spans about 8.4° by 2.9°; north is up and east to the left.

    Full story: How Herschel unlocked the secrets of star formation
    Credits: ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech), CC BY-SA 3.0 IGO

    Herschel’s view of the Taurus molecular cloud

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    Credits: ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech), CC BY-SA 3.0 IGO

    This mosaic combines several observations of the Taurus Molecular Cloud performed by ESA’s Herschel observatory. Located about 450 light-years from us, in the constellation Taurus, the Bull, this vast complex of interstellar clouds is where a myriad of stars are being born, and is the closest large region of star formation.

    Observing the sky at far-infrared and submillimetre wavelengths from 2009 to 2013, Herschel could catch the faint glow of dust grains dispersed through these clouds. Astronomers can use this glow to trace the otherwise dark gas where star formation unfolds.

    The darker, blue-hued areas throughout the image correspond to colder, less dense portions of the cloud, while the brighter, red-hued regions are the densest environments, where the star-forming activity is most intense.

    The densest regions are distributed along an intricate network of filaments, teeming with bright clumps: the seeds of future stars. This is a textbook example of the filamentary structures that were spotted by Herschel nearly everywhere in the Galaxy, demonstrating the key role of filaments in star formation.

    Embedded in the bright clump towards the top left of the image is Lynds 1544, a pre-stellar core that will later turn into a star. Here, Herschel detected water vapour – the first time this molecule was ever found in a prestellar core – in an amount that exceeds, by over 2000 times, the water content of Earth’s oceans.

    Herschel observations of the tangled structures in the top right of the image have shown that the material along filaments is not at all static. In fact, the most prominent filaments appear to be drawing matter from their surroundings through a network of lower-density filaments, known as striations, perpendicular to the main filament. In these regions, astronomers found that magnetic fields tend to be perpendicular to the densest, star-forming filaments and parallel to the striations, indicating that they must also play an important role in the processes that lead to stellar birth.

    This four-colour image combines Herschel observations at 160 microns (blue), 250 microns (green), 350 microns (split between green and red) and 500 microns (red), and spans 13.8° by 7.3°; north is up and east to the left.

    Full story: The cosmic water trail uncovered by Herschel

    Herschel’s view of the Pinwheel Galaxy

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    This image shows the Pinwheel Galaxy, also known as Messier 101, as viewed by ESA’s Herschel observatory. Lying more than 20 million light-years from us, this spiral galaxy is similar in shape to our Milky Way, but it is almost twice as large.

    Herschel’s observations at far-infrared and submillimetre wavelengths reveal the glow of cosmic dust, which is a minor but crucial ingredient in the interstellar material in the galaxy’s spiral arms. This mixture of gas and dust provides the raw material to produce the galaxy’s future generations of stars.

    The Pinwheel Galaxy is in the constellation Ursa Major, the Big Dipper. Thanks to its orientation, we can enjoy a face-on view of the beautiful spiral structure of the galaxy’s disc.

    The spiral arms are dotted with several bright, blue-hued spots of light: these are regions where large numbers of massive stars are being born.

    This three-colour image combines Herschel observations at 70 and 100 microns (blue), 160 and 250 microns (green), and 350 and 500 microns (red). North is up and east to the left.

    Full story: Herschel’s chronicles of galaxy evolution

    Herschel’s view of NGC 1097

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    Credits: ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech),

    Portrayed in this image by ESA’s Herschel observatory is NGC 1097, a barred spiral galaxy located some 50 million light-years from us, in the southern constellation Fornax, the Furnace.

    The blue regions sprinkled across the galaxy’s two spiral arms are sites of intense star formation. There, the energy from newborn stars has heated up the dust interspersed in the interstellar gas, making it glow at the far-infrared and submillimetre wavelengths probed by Herschel.

    The dwarf elliptical galaxy NGC 1097A, a small satellite of NGC 1097, can be seen as the fuzzy blue blob in the top right, halfway between the two spiral arms.

    The bright core of the NGC 1097, surrounded by a glowing ring where most of the galaxy’s prodigious star formation is taking place, conceals a supermassive black hole about a hundred million times the mass of our Sun. This black hole is devouring matter from its vicinity, causing the galactic core to shine brightly across the electromagnetic spectrum, from X-rays to radio waves.

    This galaxy was discovered – and originally identified as a nebula – in the late 18th century in optical observations by William Herschel, the astronomer after whom the observatory is named. Despite the source’s location in the southern sky, it was still visible a few degrees above the horizon at the site in England where Herschel made his observations.

    This three-colour image combines Herschel observations at 70 and 100 microns (blue), 160 and 250 microns (green), and 350 and 500 microns (red). North is up and east to the left.

    Herschel’s view of a star nursery

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    Credits: ESA/Herschel/NASA/JPL-Caltech; acknowledgement: R. Hurt (JPL-Caltech), CC BY-SA 3.0 IGO

    This image shows Rho Ophiuchi, a vast stellar nursery where new stars take shape from billowing clouds of gas, as viewed by ESA’s Herschel observatory. Located about 440 light-years from us, in the constellation Ophiuchus, the Serpent Bearer, Rho Ophiuchi is one of the nearest star-forming regions to Earth.

    Some of these clouds appear dark when observed at optical and near-infrared wavelengths owing to the presence of dust, a minor but crucial component of the interstellar medium that pervades our Galaxy. However, they appeared anything but dark to the infrared eye of Herschel.

    Observing the sky at far-infrared and submillimetre wavelengths from 2009 to 2013, Herschel could catch the faint glow of dust grains interspersed in these clouds. Astronomers can use this glow to trace the otherwise dark gas where star formation unfolds.

    Herschel’s view reveals a tangled network of filaments, weaving their way from the darker, less dense regions on the left of the image towards the brighter, denser parts of the cloud, on the right. The bright clumps embedded in the cloud are the seeds of future stars and planets.

    Filaments like these were uncovered by Herschel throughout the Galaxy, indicating that these structures play a fundamental role in the processes that lead to the birth of stars.

    This three-colour image combines Herschel observations at 70 microns (blue), 160 microns (green) and 250 microns (red), and spans 7.9° by 4.6°; north is up and east to the left.

    See the full article here .

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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.

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  • richardmitnick 9:23 pm on September 21, 2017 Permalink | Reply
    Tags: , , , , Cosmology, ,   

    From Penn State: “Mystery solved: Super-energetic space particles crash to Earth from far away” 

    Penn State Bloc

    Pennsylvania State University

    September 21, 2017

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    An image of the Earth showing the continent of South America, with faint white streaks representing cosmic rays streaming toward the Pierre Auger Observatory in Argentina. Image: Pierre Auger Observatory

    Super-energetic space particles, which were thought to have been blasted toward Earth from somewhere outside our solar system, now have been discovered to be from very far away indeed — from far outside our Milky Way galaxy. The discovery was made by an international team that includes Penn State scientists and the Pierre Auger Collaboration, using the largest cosmic-ray instrument ever built, the Pierre Auger Observatory in Argentina. A paper describing the discovery will be published in the journal Science on Sept. 22.


    This animation illustrates the long journey of high-energy cosmic waves from the time they are shot into space from powerful events in galaxies far away from our Milky Way Galaxy until they eventually crash on Earth, leaving clues among the large array of cosmic-ray detectors in western Argentina, the Pierre Auger Observatory. Penn State scientists are members of the Pierre Auger Consortium.
    Pierre Auger Collaboration

    “After more than a century since cosmic rays were first detected, this is the first truly significant result from our analysis of the detections, which now have revealed the distant origin of these ultra-high-energy cosmic rays,” said Miguel Mostafá at Penn State. He and Stephane Coutu — both professors of physics and of astronomy and astrophysics and Fellows of the American Physical Society — lead teams of students and post-doctoral scientists in research at Penn State’s Pierre Auger Collaboration group.

    Pierre Auger Observatory in the western Mendoza Province, Argentina, near the Andes

    “Now we know that the highest-energy particles in the universe came from other galaxies in our cosmological neighborhood,” Mostafá said.

    Mostafá and Coutu have been working on the project since 1996 and 1997, respectively, with support from the U.S. National Science Foundation. Mostafá has been a coordinator of the Auger team in charge of this analysis of cosmic-ray arrival directions, and is one of the corresponding authors on the Science article.

    Although the Pierre Auger Collaboration’s discovery clearly shows an origin outside our Milky Way galaxy, the specific sources that are producing the particles have not yet been discovered. “We are now considerably closer to solving the mystery of where and how these extraordinary particles are produced, a question of great interest to astrophysicists,” said Karl-Heinz Kampert, professor of physics at the University of Wuppertal in Germany and spokesperson for the Pierre Auger Collaboration.

    See the full article here .

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    Penn State Campus

    WHAT WE DO BEST

    We teach students that the real measure of success is what you do to improve the lives of others, and they learn to be hard-working leaders with a global perspective. We conduct research to improve lives. We add millions to the economy through projects in our state and beyond. We help communities by sharing our faculty expertise and research.

    Penn State lives close by no matter where you are. Our campuses are located from one side of Pennsylvania to the other. Through Penn State World Campus, students can take courses and work toward degrees online from anywhere on the globe that has Internet service.

    We support students in many ways, including advising and counseling services for school and life; diversity and inclusion services; social media sites; safety services; and emergency assistance.

    Our network of more than a half-million alumni is accessible to students when they want advice and to learn about job networking and mentor opportunities as well as what to expect in the future. Through our alumni, Penn State lives all over the world.

    The best part of Penn State is our people. Our students, faculty, staff, alumni, and friends in communities near our campuses and across the globe are dedicated to education and fostering a diverse and inclusive environment.

     
  • richardmitnick 3:15 pm on September 21, 2017 Permalink | Reply
    Tags: , , , Cosmology, ,   

    From COSMOS: “Tougher, shinier mirrors boost telescope power” 

    Cosmos Magazine bloc

    COSMOS Magazine

    21 September 2017
    Andrew Masterson

    1
    The 10-metre mirror array at Hawaii’s Keck Telescope. Laurie Hatch, UCSC

    The world’s big astronomical telescopes could soon all get a performance upgrade without the need for installing bigger mirrors, thanks to a collaboration between materials scientists and astronomers at the University of California, Santa Cruz, in the US.

    One key property of the mirrors used in astronomical telescopes is, of course, reflectiveness. Another, however, is durability – and the intersection of the two represents a trade-off.

    Most big telescopes use mirrors coated in aluminium, which is a comparatively tough material that can survive the sometimes harsh environments in which observatories are situated, as well as being able to withstand the potentially damaging effects of being manhandled.

    Silver makes for a much more efficient mirror because it is much more reflective. However, it is also fragile, and prone to damage and corrosion.

    Tackling this problem after a conversation with a despairing astronomer, a team led by materials scientist Nobuhiko Kobayashi has formulated a tough but ultra-thin coating that can keep silver protected without reducing or distorting its reflective properties.

    The team formulated several new alloys, using various combinations of fluoride, magnesium and aluminium oxides. These were then deposited on a silver surface, using an electron beam, in a molecule-by-molecule process called atomic layer deposition.

    The best-performing formulation – which rejoices in the name MgAl2O4, Al2O3 – enabled high reflectance at wavelengths between 340 nanometres and the mid-infrared spectrum. It remained stable even when exposed to 80% humidity and 80 degree Celsius temperatures for 10 days in a row.

    Both the specific formulation and the application method have been patented by their inventors. The mechanical limit of the process at present means the largest mirror that can be coated has a diameter of 0.9 metres.

    Kobayashi and his colleagues are working on doubling this – an upper limit, they say, that will allow the mirrors in even the world’s largest telescopes to be converted to silver. The main mirrors of the Keck Telescope in Hawaii, for instance, comprise a 10-metre span, but are made up of 1.8 metre-wide components.

    “It is by far the cheapest way to make our telescopes effectively bigger,” says co-author Michael Bolte. “The reason we want bigger telescopes is to collect more light, so if your mirrors reflect more light it’s like making them bigger.”

    The research is published in the SPIE Digital Library.

    See the full article here .

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  • richardmitnick 2:44 pm on September 21, 2017 Permalink | Reply
    Tags: , , , , Cosmology,   

    From CfA: “Fast Radio Bursts May Be Firing Off Every Second” 

    Harvard Smithsonian Center for Astrophysics


    Center For Astrophysics

    September 21, 2017
    Megan Watzke
    Harvard-Smithsonian Center for Astrophysics
    +1 617-496-7998
    mwatzke@cfa.harvard.edu

    Peter Edmonds
    Harvard-Smithsonian Center for Astrophysics
    +1 617-571-7279
    pedmonds@cfa.harvard.edu

    1
    This artist’s impression shows part of the cosmic web, a filamentary structure of galaxies that extends across the entire sky. The bright blue, point sources shown here are the signals from Fast Radio Bursts (FRBs) that may accumulate in a radio exposure lasting for a few minutes. The radio signal from an FRB lasts for only a few thousandths of a second, but they should occur at high rates. M. Weiss/CfA

    When fast radio bursts, or FRBs, were first detected in 2001, astronomers had never seen anything like them before. Since then, astronomers have found a couple of dozen FRBs, but they still don’t know what causes these rapid and powerful bursts of radio emission.

    For the first time, two astronomers from the Harvard-Smithsonian Center for Astrophysics (CfA) have estimated how many FRBs should occur over the entire observable universe. Their work indicates that at least one FRB is going off somewhere every second.

    “If we are right about such a high rate of FRBs happening at any given time, you can imagine the sky is filled with flashes like paparazzi taking photos of a celebrity,” said Anastasia Fialkov of the CfA, who led the study. “Instead of the light we can see with our eyes, these flashes come in radio waves.”

    To make their estimate, Fialkov and co-author Avi Loeb assumed that FRB 121102, a fast radio burst located in a galaxy about 3 billion light years away, is representative of all FRBs. Because this FRB has produced repeated bursts since its discovery in 2002, astronomers have been able to study it in much more detail than other FRBs. Using that information, they projected how many FRBs would exist across the entire sky.

    “In the time it takes you to drink a cup of coffee, hundreds of FRBs may have gone off somewhere in the Universe,” said Avi Loeb. “If we can study even a fraction of those well enough, we should be able to unravel their origin.”

    While their exact nature is still unknown, most scientists think FRBs originate in galaxies billions of light years away. One leading idea is that FRBs are the byproducts of young, rapidly spinning neutron stars with extraordinarily strong magnetic fields.

    Fialkov and Loeb point out that FRBs can be used to study the structure and evolution of the Universe whether or not their origin is fully understood. A large population of faraway FRBs could act as probes of material across gigantic distances. This intervening material blurs the signal from the cosmic microwave background (CMB), the left over radiation from the Big Bang.

    CMB per ESA/Planck

    ESA/Planck

    A careful study of this intervening material should give an improved understanding of basic cosmic constituents, such as the relative amounts of ordinary matter, dark matter and dark energy, which affect how rapidly the universe is expanding.

    FRBs can also be used to trace what broke down the “fog” of hydrogen atoms that pervaded the early universe into free electrons and protons, when temperatures cooled down after the Big Bang. It is generally thought that ultraviolet (UV) light from the first stars traveled outwards to ionize the hydrogen gas, clearing the fog and allowing this UV light to escape. Studying very distant FRBs will allow scientists to study where, when and how this process of “reionization” occurred.

    Reionization era and first stars, Caltech

    “FRBs are like incredibly powerful flashlights that we think can penetrate thise fog and be seen over vast distances,” said Fialkov. “This could allow us to study the ‘dawn’ of the universe in a new way.”

    The authors also examined how successful new radio telescopes – both those already in operation and those planned for the future – may be at discovering large numbers of FRBs. For example, the Square Kilometer Array (SKA) currently being developed will be a powerful instrument for detecting FRBs.

    SKA Square Kilometer Array

    The new study suggests that over the whole sky the SKA may be able to detect more than one FRB per minute that originates from the time when reionization occurred.

    The Canadian Hydrogen Intensity Mapping Experiment (CHIME), that recently began operating, will also be a powerful machine for detecting FRBs, although its ability to detect the bursts will depend on their spectrum, i.e. how the intensity of the radio waves depends on wavelength.

    CHIME Canadian Hydrogen Intensity Mapping Experiment A partnership between the University of British Columbia McGill University, at the Dominion Radio Astrophysical Observatory in British Columbia

    If the spectrum of FRB 121102 is typical then CHIME may struggle to detect FRBs. However, for different types of spectra CHIME will succeed.

    The paper by Fialkov and Loeb describing these results was published in the September 10, 2017 issue of The Astrophysical Journal Letters.

    See the full article here .

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

     
  • richardmitnick 8:45 am on September 21, 2017 Permalink | Reply
    Tags: , , , Cosmology, CSIROscope, Expect the unexpected from the big-data boom in radio astronomy,   

    From CSIROscope: “Expect the unexpected from the big-data boom in radio astronomy” 

    CSIRO bloc

    CSIROscope

    21 September 2017
    Ray Norris, Western Sydney University & CSIRO Honorary Fellow

    1
    Antennas of the Australian SKA Pathfinder (ASKAP) at CSIRO’s Murchison Radio-astronomy Observatory in Western Australia. CSIRO, Author provided

    SKA Square Kilometer Array

    Radio astronomy is undergoing a major boost, with new technology gathering data on objects in our universe faster than astronomers can analyse.

    But once that data is scrutinised it could lead to some amazing new discoveries, as I explain in my review of the state of radio astronomy, published today in Nature Astronomy.

    Over the next few years, we will see the universe in a very different light, and we are likely to make completely unexpected discoveries.

    ___________________________________________________________________
    Read more: The Australian Square Kilometre Array Pathfinder finally hits the big-data highway
    ___________________________________________________________________

    Radio telescopes view the sky using radio waves and mainly see jets of electrons travelling at the speed of light, propelled by super-massive black holes. That gives a very different view to the one we see when observing a clear night sky using visible light, which mainly sees light from stars.

    Black holes were only found in science fiction before radio astronomers discovered them in quasars. It now seems that most galaxies, including our own Milky Way, have a super-massive black hole at their centre.

    From early discoveries

    Radio waves from space were detected by the American Karl Jansky in the 1930s. Since then, radio telescopes – such as the 64-metre dish at Parkes, in New South Wales – increased the number of known radio sources in the sky from one (in 1940) to a few hundred thousand.

    NRAO/Karl V Jansky VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    2
    A composite image of a radio galaxy with radio in red, optical in white and X-ray in blue. An X-ray jet emanates from the environs of a super-massive black hole at the centre, powering two diffuse lobes (shown in red) of radio emission, which dominate the appearance at radio wavelengths. Emil Lenc, Author provided [telescopes[s] not credited.

    Then, around the turn of the millennium, four projects driven by new technology suddenly increased the number of known radio sources from a few hundred thousand to about 2.5 million. They were the Westerbork Northern Sky Survey (WENSS, NRAO VLA Sky Survey (NVSS, Faint Images of the Radio Sky at Twenty-cm (FIRST and the Sydney University Molonglo Sky Survey (SUMSS in The Netherlands, United States and Australia.

    Westerbork Synthesis Radio Telescope, Netherlands

    U Sidney Molonglo Observatory Synthesis Telescope (MOST), Hoskinstown, Australia

    For almost the next two decades there was no significant increase in this number, because nobody could significantly improve on what those four projects had done.

    A group of new telescopes in Australia, The Netherlands, the United States, India and South Africa are about to unleash new technologies that will generate another surge in our knowledge of the radio sky.

    Leading them, in terms of numbers of sources, is ATNF Australia’s Evolutionary Map of the Universe (EMU) project, running on CSIRO’s new A$188-million Australian Square Kilometre Array Pathfinder (ASKAP) telescope in Western Australia.

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    For ASKAP, the new technology is CSIRO’s revolutionary phased array feed, which allows ASKAP to view enormous areas of the sky at once.

    SKA ASKAP Phased Array

    As a result, EMU alone will raise the number of radio sources to about 70 million, compared to the 2.5 million sources discovered so far by all radio telescopes in the world over the entire history of radio astronomy.

    3
    The graph shows two spikes in number of radio sources detected in major surveys over the years, from the birth of radio astronomy to the next-generation surveys. Ray Norris, Author provided.

    A change in radio astronomy

    This huge surge in humankind’s knowledge of the radio sky has several consequences.

    First, we expect to answer some of the major questions in astrophysics, such as understanding why super-massive black holes seem so common in the universe, how that regulates the growth and evolution of galaxies and how galaxies swarm together to form clusters.

    Second, it will change the way we do radio astronomy. At the moment, if I want to know what a galaxy looks like at radio wavelengths, chances are I’ll have to win time competitively on a major radio telescope to study my galaxy.

    But I’ll soon be able to go to the web and observe my galaxy in data already collected by EMU or one of the other mega-projects. So most radio astronomy will be done by a web search rather than by a new observation. The role of major radio telescopes will change from finding new objects to studying known objects in exquisite detail.

    Third, it will change the way that astronomers do their astronomy at other wavelengths. At the moment, only a small minority of galaxies have been studied at radio wavelengths.

    From now on, most galaxies being studied by the average astronomer will have excellent radio data. This adds a new tool that can routinely be used to uncover the physics of galaxies, opening wide the radio window on the universe.

    Fourth, having such large volumes of data changes the way we do science. For example, if I want to understand how the gravitational field of nearby galaxies bends light from distant galaxies, I currently find the best single example I can, and spend night after night on the telescope to study the process in detail.

    In future, I will be able to correlate the millions of background galaxies with the millions of foreground galaxies, using data downloaded from the web to understand the process in even greater detail.

    Fifth, and probably most importantly, history tells us that when we observe the universe in a new way, we tend to stumble across new objects or new phenomena that we didn’t even suspect were there. Pulsars, quasars, dark energy and dark matter were all found in this way.

    4
    Radio astronomy may reveal more about the supermassive black hole, typically found at the heart of many galaxies. ESO/L. Calçada/Artists impression, CC BY.

    New discoveries

    So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

    Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

    Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

    With the right tools and careful insight, who knows what we might find.

    See the full article here .

    [All of this is happening while in the U.S. the NSF is seeking to defund Radio Astronomy. They have already dropped the Greenbank Observatory which has some protection in a $2 million/yr 5 year contract with Uri Milner’s Breakthrough Listen project

    Breakthrough Listen Project

    1

    Lick Automated Planet Finder telescope, Mount Hamilton, CA, USA



    GBO radio telescope, Green Bank, West Virginia, USA


    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

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    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    So what can we expect these new radio projects to discover? We have no idea, but history tells us that they are almost certain to deliver some major surprises.

    Making these new discoveries may not be so simple. Gone are the days when astronomers could just notice something odd as they browse their tables and graphs.

    Nowadays, astronomers are more likely to be distilling their answers from carefully-posed queries to databases containing petabytes of data. Human brains are just not up to the job of making unexpected discoveries in these circumstances, and instead we will need to develop “learning machines” to help us discover the unexpected.

    With the right tools and careful insight, who knows what we might find.

    CSIRO campus

    CSIRO, the Commonwealth Scientific and Industrial Research Organisation, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

     
  • richardmitnick 8:01 am on September 21, 2017 Permalink | Reply
    Tags: , , , Cosmology, Hubble’s Contentious Constant,   

    From Hubble: “Hubble’s Contentious Constant” video 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    Visit http://science.nasa.gov/ for more.

    There are two leading ways to measure the universe’s rate of expansion, and for fifteen years, they more or less agreed with one another. Not anymore, and that’s a big deal.
    Category
    Science & Technology
    License
    Creative Commons Attribution license (reuse allowed)

    See the full article here .

    Please help promote STEM in your local schools.

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    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 1:14 pm on September 20, 2017 Permalink | Reply
    Tags: 288P, , , , Cosmology, Hubble discovers a unique type of object in the Solar System, , The observations also revealed ongoing activity in the binary system, Two asteroids orbiting each other and exhibiting comet-like features   

    From Hubble: “Hubble discovers a unique type of object in the Solar System” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    20 September 2017
    Jessica Agarwal
    Max Planck Institute for Solar-System Research
    Göttingen, Germany
    Tel: +49 551 384 979 438
    Email: agarwal@mps.mpg.de

    Lauren Fuge
    ESA/Hubble, Public Information Officer
    Garching bei München, Germany
    Email: lfuge@partner.eso.org

    1
    Image credit: NASA, ESA

    2
    Image of binary asteroid system 288P

    3
    This image depicts the two areas where most of the asteroids in the Solar System are found: the asteroid belt between Mars and Jupiter, and the trojans, two groups of asteroids moving ahead of and following Jupiter in its orbit around the Sun. The binary asteroid 288P is part of the asteroid belt. Credit: ESA/Hubble, M. Kornmesser

    With the help of the NASA/ESA Hubble Space Telescope, a German-led group of astronomers have observed the intriguing characteristics of an unusual type of object in the asteroid belt between Mars and Jupiter: two asteroids orbiting each other and exhibiting comet-like features, including a bright coma and a long tail. This is the first known binary asteroid also classified as a comet. The research is presented in a paper published in the journal Nature this week.

    In September 2016, just before the asteroid 288P made its closest approach to the Sun, it was close enough to Earth to allow astronomers a detailed look at it using the NASA/ESA Hubble Space Telescope [1].

    The images of 288P, which is located in the asteroid belt between Mars and Jupiter, revealed that it was actually not a single object, but two asteroids of almost the same mass and size, orbiting each other at a distance of about 100 kilometres. That discovery was in itself an important find; because they orbit each other, the masses of the objects in such systems can be measured.

    But the observations also revealed ongoing activity in the binary system. “We detected strong indications of the sublimation of water ice due to the increased solar heating — similar to how the tail of a comet is created,” explains Jessica Agarwal (Max Planck Institute for Solar System Research, Germany), the team leader and main author of the research paper. This makes 288P the first known binary asteroid that is also classified as a main-belt comet.

    Understanding the origin and evolution of main-belt comets — asteroids orbiting between Mars and Jupiter that show comet-like activity — is a crucial element in our understanding of the formation and evolution of the whole Solar System. Among the questions main-belt comets can help to answer is how water came to Earth [2]. Since only a few objects of this type are known, 288P presents itself as an extremely important system for future studies.

    The various features of 288P — wide separation of the two components, near-equal component size, high eccentricity and comet-like activity — also make it unique among the few known wide asteroid binaries in the Solar System. The observed activity of 288P also reveals information about its past, notes Agarwal: “Surface ice cannot survive in the asteroid belt for the age of the Solar System but can be protected for billions of years by a refractory dust mantle, only a few metres thick.”

    From this, the team concluded that 288P has existed as a binary system for only about 5000 years. Agarwal elaborates on the formation scenario: “The most probable formation scenario of 288P is a breakup due to fast rotation. After that, the two fragments may have been moved further apart by sublimation torques.”

    The fact that 288P is so different from all other known binary asteroids raises some questions about whether it is not just a coincidence that it presents such unique properties. As finding 288P included a lot of luck, it is likely to remain the only example of its kind for a long time. “We need more theoretical and observational work, as well as more objects similar to 288P, to find an answer to this question,” concludes Agarwal.
    Notes

    [1] Like any object orbiting the Sun, 288P travels along an elliptical path, bringing it closer and further away to the Sun during the course of one orbit.

    [2] Current research indicates that water came to Earth not via comets, as long thought, but via icy asteroids.
    More information

    The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

    The international team of astronomers in this study consists of Jessica Agarwal (Max Planck Institute for Solar System Research, Göttingen, Germany), David Jewitt (Department of Earth, Planetary and Space Sciences and Department of Physics and Astronomy, University of California at Los Angeles, USA), Max Mutchler (Space Telescope Science Institute, Baltimore, USA), Harold Weaver (The Johns Hopkins University Applied Physics Laboratory, Maryland, USA) and Stephen Larson (Lunar and Planetary Laboratory, University of Arizona, Tucson, USA).

    The results were released in the paper “A binary main belt comet” to be published in Nature.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    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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