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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Is Dark Matter Real?
    https://www.livescience.com/59814-is-dark-matter-real.html

    Many science-savvy people take it for granted that the universe is made not only of Carl Sagan's oft-quoted "billions and billions" of galaxies, but also a vast
    amount of an invisible substance called dark matter. This odd matter is thought to be a new kind of subatomic particle that doesn't interact via electromagnetism,
    nor the strong and weak nuclear forces. Dark matter is also supposed to be five times more prevalent in the universe than the ordinary matter of atoms.

    However, the reality is that dark matter's existence has not yet been proved. Dark matter is still a hypothesis, albeit a rather well-supported one. Any scientific
    theory has to make predictions, and if it's right, then the measurements you do should line up with the predictions. The same goes for dark matter. For instance,
    dark matter theories make predictions for how fast galaxies are rotating. But, until now, measurements made of the detailed dark matter distribution at the center
    of low mass galaxies didn't line up with those predictions.

    A recent calculation has changed that. The calculation helps resolve the conundrum of the Tully-Fisher relation, which compares the visible, or ordinary, matter of a
    galaxy to its rotational velocity. In very simplified terms, scientists have found that the more massive (and therefore brighter) a spiral galaxy is, the faster it spins.
    VIRGO
    VIRGO --- ---
    NASA Neutron star mission begins science operations
    https://phys.org/news/2017-07-nasa-neutron-star-mission-science.html

    NASA's new Neutron star Interior Composition Explorer (NICER) mission to study
    the densest observable objects in the universe has begun science operations.

    Launched June 3 on an 18-month baseline mission, NICER will help scientists
    understand the nature of the densest stable form of matter located deep in
    the cores of neutron stars using X-ray measurements.

    VIRGO
    VIRGO --- ---
    Podcast: On July 10, researchers using NASA’s Stratospheric Observatory for Infrared Astronomy, or SOFIA, will attempt to study
    the environment around a distant Kuiper Belt Object, 2014 MU69, which is the next flyby target for NASA’s New Horizons spacecraft.

    http://pluto.jhuapl.edu/common/content/videos/podcasts/KBO%20podcast%203%20v2_640x360.mp4

    VIRGO
    VIRGO --- ---
    https://saturn.jpl.nasa.gov/resources/7707/

    This view looks toward the Saturn-facing hemisphere of Enceladus (313 miles or 504 kilometers across). North
    is up. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 13, 2017.

    The view was acquired at a distance of approximately 502,000 miles (808,000 kilometers) from Enceladus and at
    a sun-Enceladus-spacecraft, or phase, angle of 176 degrees. Image scale is 3 miles (5 kilometers) per pixel.

    VIRGO
    VIRGO --- ---
    The Juno Great Red Spot images are amazing, but this 3D image showing the depth of the storms is just breath taking : space
    https://www.reddit.com/r/space/comments/6njf8q/the_juno_great_red_spot_images_are_amazing_but/

    SLAPPY
    SLAPPY --- ---
    Odhalující okultace
    https://slunecnisoustava.blogspot.cz/2017/07/odhalujici-okultace.html

    Astronomické výpravy za lovením stínů planetky 2014 MU69 si mezi lidmi získaly nemalou pozornost. V dnešním shrnutí se podíváme, jak se pozorovatelská kampaň #MU69occ vyvíjí, ale zmíníme i další zajímavé okultace. Před vzdálenými hvězdami totiž projde největší z kentaurů a také jediný velký retrográdní měsíc...

    VIRGO
    VIRGO --- ---
    Astronomers discover one of the brightest galaxies known
    https://phys.org/news/2017-07-astronomers-brightest-galaxies.html

    Thanks to an amplified image produced by a gravitational lens, and the Gran Telescopio CANARIAS a team of scientists
    from the Polytechnic University of Cartagena and the Instituto de Astrofísica de Canarias have discovered one of the
    brightest galaxies known from the epoch when the universe had 20 percent of its present age.

    Using this effect, a team of scientists from the Instituto de Astrofisica de Canarias (IAC) led by researcher Anastasio
    Díaz-Sánches of the Polytechnic University of Cartagena (UPT) has discovered a very distant galaxy, some 10 thousand
    million light years away, about a thousand times brighter than the Milky Way. It is the brightest of the submillimetre
    galaxies, called this because of their very strong emissionin the far infrared. To measure it they used the Gran
    Telescopio Canarias (GTC) at the Roque de los Muchachos Observatory (Garafía, La Palma).

    VIRGO
    VIRGO --- ---
    This is what it would take to kill all life on Earth | Science | AAAS
    http://www.sciencemag.org/news/2017/07/what-it-would-take-kill-all-life-earth

    A giant asteroid crashing into our planet would instantly kill off millions of animals. But the aftermath of such an impact would be even more disastrous:
    Tsunamis, earthquakes, and vast clouds of dust blocking out the sun would lead to crop failure and mass extinction. Sixty-five million years ago, just such
    an event killed off 75% of species on Earth. But to really wipe life off the planet, it would take an astrophysical event so powerful that Earth’s oceans
    would literally boil away, according to a new study. The heat and cosmic radiation would make Earth inhospitable even to tardigrades, among the hardiest
    organisms ever discovered.

    “They’ve taken a grand question—how resilient is life?—and turned [it] into a well-posed calculation, by focusing on the energy required to boil Earth’s
    oceans,” says Joshua Winn, an exoplanets expert at Princeton University, who was not involved in the study. “It’s an awful lot of energy.”

    Researchers first calculated the amount of energy it would take to bring all Earth’s water above 100°C: 6 x 1022 joules, about a hundred times more than
    total annual energy consumption by humans, or a trillion times the energy needed for the space shuttle to lift off. Translated into cataclysms, it would
    take the energy given off by the impact of an asteroid the size of Vesta or Pallas, among the solar system’s biggest, they report today in Scientific
    Reports. Other options: exploding stars known as supernovae or gamma ray bursts, highly energetic explosions in outer space.

    VIRGO
    VIRGO --- ---
    Study finds our Sun is like other stars, resolving mystery
    https://phys.org/news/2017-07-sun-stars-mystery.html

    Our Sun is much like other stars, and not an anomaly because of its magnetic poles that flip every 11 years, scientists said Thursday.

    The report in the journal Science aims to lay to rest the controversy over whether our solar system's star is cyclic, like other nearby,
    solar-type stars. "We have shed light on a fundamental mechanism which determines the length of these cycles, which helps us understand
    the cycle itself over the long-term," lead author Antoine Strugarek, a researcher at the University of Montreal, told AFP.

    VIRGO
    VIRGO --- ---
    VIRGO: NASA Video Soars over Pluto’s Majestic Mountains and Icy Plains
    https://www.nasa.gov/feature/nasa-video-soars-over-pluto-s-majestic-mountains-and-icy-plains

    New Horizons Flyover of Pluto
    https://www.youtube.com/watch?v=g1fPhhTT2Oo


    New Horizons Flyover of Charon
    https://www.youtube.com/watch?v=f0Q7O7TZ7Ks
    VIRGO
    VIRGO --- ---
    New Horizons Unveils New Maps of Pluto, Charon on Flyby Anniversary
    https://www.nasa.gov/feature/new-horizons-unveils-new-maps-of-pluto-charon-on-flyby-anniversary

    On July 14, 2015, NASA’s New Horizons spacecraft made its historic flight through the Pluto system – providing the first close-up images of Pluto
    and its moons and collecting other data that has transformed our understanding of these mysterious worlds on the solar system’s outer frontier.

    Scientists are still analyzing and uncovering data that New Horizons recorded and sent home after the encounter. On the two-year anniversary of
    the flyby, the team is unveiling a set of detailed, high-quality global maps of Pluto and its largest moon, Charon.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/goddard/2017/hubble-traps-a-lynx-barred-spiral-0

    Discovered by British astronomer William Herschel over 200 years ago, NGC 2500 lies about 30 million light-years away
    in the northern constellation of Lynx. As this NASA/ESA Hubble Space Telescope image shows, NGC 2500 is a particular
    kind of spiral galaxy known as a barred spiral, its wispy arms swirling out from a bright, elongated core.

    VIRGO
    VIRGO --- ---
    Complex Gas Motion in the Centre of the Milky Way - Communications and Marketing - Heidelberg University
    http://www.uni-heidelberg.de/presse/news2017/pm20170713_milchstrasse_en.html

    How does the gas in the centre of the Milky Way behave? Researchers from Heidelberg University, in collaboration with colleagues
    from the University of Oxford, recently investigated the motion of gas clouds in a comprehensive computer simulation. The new model
    finally makes it possible to conclusively explain this complex gas motion. Astrophysicists Dr Mattia C. Sormani (Heidelberg) and Matthew
    Ridley (Oxford) conducted the research, on Heidelberg’s part, at the Collaborative Research Centre "The Milky Way System" (CRC 881).

    VIRGO
    VIRGO --- ---
    Take a 360° spin through the heart of the sun | Science | AAAS
    http://www.sciencemag.org/news/2017/07/take-360-spin-through-heart-sun

    360 Video: Inside the heart of a star's magnetic field.
    https://www.youtube.com/watch?v=eSoyqFcK22k
    VIRGO
    VIRGO --- ---
    Shedding light on Galaxies’ rotation secrets | SISSA
    http://www.sissa.it/news/shedding-light-galaxies%E2%80%99-rotation-secrets

    A NEW STUDY PUBLISHED IN THE ASTROPHYSICAL JOURNAL

    The dichotomy concerns the so-called angular momentum (per unit mass), that in physics is a measure of size and rotation velocity.
    Spiral galaxies are found to be strongly rotating, with an angular momentum higher by a factor of about 5 than ellipticals. What is
    the origin of such a difference? An international research team investigated the issue in a study just published in The Astrophysical
    Journal. The team was led by SISSA Ph.D. student JingJing Shi under the supervision of Andrea Lapi and Luigi Danese, and in collaboration
    with Huiyuan Wang from USTC (Hefei) and Claudia Mancuso from IRA-INAF (Bologna).

    The researchers inferred from observations the amount of gas fallen into the central region of a developing galaxy, where most of the star
    formation takes places. The outcome is that in elliptical galaxies only about 40% of the available gas fell into that central region. More
    relevantly, this gas fueling star formation was characterized by a rather low angular momentum since the very beginning. This is in stark
    contrast with the conditions found in spirals, where most of the gas ending up in stars had an angular momentum appreciably higher.

    VIRGO
    VIRGO --- ---
    Researchers describe one of the most massive large-scale structures in the universe
    https://phys.org/news/2017-07-massive-large-scale-universe.html

    A team of astronomers from the Inter University Centre for Astronomy & Astrophysics (IUCAA), and Indian Institute of Science Education and Research (IISER),
    both in Pune, India, and members of two other Indian universities, have identified a previously unknown, extremely large supercluster of galaxies located in
    the direction of constellation Pisces. This is one of the largest known structures in the nearby Universe, and is at a distance of 4,000 million (400 crore)
    light-years away from us.

    This novel discovery is being published in the latest issue of The Astrophysical Journal, the premier research journal of the American Astronomical Society.

    Large-scale structures in the Universe are found to be hierarchically assembled, with galaxies, together with associated gas, and dark matter, being clumped
    in clusters, which are organized with other clusters, smaller groups, filaments, sheets and large empty regions ("voids") in a pattern called the "Cosmic web"
    which spans the observable Universe.

    Superclusters are the largest coherent structures in the Cosmic Web. A Supercluster is a chain of galaxies and galaxy clusters, bound by gravity, often
    stretching to several hundred times the size of clusters of galaxies, consisting of tens of thousands of galaxies. This newly-discovered 'Saraswati'
    supercluster, for instance, extends over a scale of 600 million light-years and may contain the mass equivalent of over 20 million billion suns.

    VIRGO
    VIRGO --- ---
    Long duration M2.4 solar flare erupts, Earth-directed CME
    https://watchers.news/2017/07/14/m2-4-solar-flare-july-14-2017/

    Active Region 2665 produced a long duration solar flare measuring M2.4 at its peak time on July 14, 2017. Today's event lasted for more than 2 hours;
    it started at 01:07, peaked at 02:09 and ended at 03:24 UTC. The eruption produced a coronal mass ejection (CME) which appears to have an Earth-directed
    component. This region is now moving away from the center of the Earth-facing Sun but could still produce moderate to strong eruptions in the days ahead.

    The eruption was associated with a Type IV radio emission. Type IV emissions occur in association with major eruptions on the Sun and are typically
    associated with strong coronal mass ejections and solar radiation storms. This CME will likely reach Earth late Monday, July 16 or early Tuesday, July 17.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/jpl/pia21782/mars-and-the-amazing-technicolor-ejecta-blanket

    This image from NASA's Mars Reconnaissance Orbiter shows the exposed bedrock of an ejecta blanket of an unnamed crater in the Mare Serpentis region of Mars. Ejecta,
    when exposed, are truly an eye-opening feature, as they reveal the sometimes exotic subsurface, and materials created by impacts (close-up view). This ejecta shares
    similarities to others found elsewhere on Mars, which are of particular scientific interest for the extent of exposure and diverse colors. (For example, the Hargraves
    Crater ejecta, in the Nili Fossae trough region, was once considered as a candidate landing site for the next NASA Mars rover 2020.)

    VIRGO
    VIRGO --- ---
    Asteroid 2012 TC4 to safely flyby Earth on October 12, 2017
    https://watchers.news/2017/07/13/asteroid-2012-tc4-october-12-2017/

    A small Apollo-class asteroid named 2012 TC4 will safely flyby Earth at 06:07 UTC ( ± 02:51) on October 12, 2012.

    This asteroid has not ben seen since it was discovered in October 2012, when it flew past Earth at about 0.25 LD
    (¼ the distance from Earth to the Moon), so it's difficult to know how close it will pass us this time. However,
    as it starts to approach us this summer, large telescopes will be used to re-establish its precise trajectory and
    narrow the uncertainty.

    "We know the orbit of 2012 TC4 well enough to be certain that it won’t hit Earth," said Paul Chodas, manager of
    the Center for Near-Earth Object Studies (CNEOS), at NASA’s Jet Propulsion Laboratory.

    VIRGO
    VIRGO --- ---
    A New Search for Extrasolar Planets from the Arecibo Observatory - Planetary Habitability Laboratory @ UPR Arecibo
    http://phl.upr.edu/press-releases/barnard

    The National Science Foundation’s Arecibo Observatory and the Planetary Habitability Laboratory of the University of Puerto Rico
    at Arecibo joined the Red Dots project in the search for new planets around our nearest stars. This new collaboration will
    simultaneously observe in both the optical and radio spectrum Barnard’s Star, a popular star in the science fiction literature.

    Barnard's star is a low-mass red dwarf almost six light-years away and the second-closest stellar system to our Sun after
    the Alpha Centauri triple-star system. There are hints of a possible super-Earth mass planet in a cold orbit around this star.

    The Arecibo Observatory has a new campaign to observe nearby red dwarf stars with planets. The purpose of this campaign is to detect
    radio emissions from these stars, such as from flares, to help characterize their radiation and magnetic environment and any potential
    perturbations due to other bodies. These perturbations might reveal the presence of new sub-stellar objects including planets.

    Barnard’s Star will be the eighth red dwarf star to be recently observed by the Arecibo Observatory. Results from Gliese 436, Ross 128,
    Wolf 359, HD 95735, BD +202465, V* RY Sex, and K2-18 are currently being analyzed. These observations are led by Prof. Abel Méndez,
    Director of the Planetary Habitability Laboratory of the University of Puerto Rico at Arecibo in collaboration with Dr. Jorge Zuluaga
    from the Universidad de Antioquia in Colombia.

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