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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
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    Meteor, Aurora
    Taken by amy johnson on September 1, 2016 @ Denali National Park -Wonder Lake Campground

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    After the first week in space, OSIRIS-REx has traveled 17 058 149 km and is 3 201 147 km from Earth.

    Dante Lauretta

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    YaleNews | Ch-ch-ch-changes in a distant quasar
    http://news.yale.edu/2016/09/15/ch-ch-ch-changes-distant-quasar

    Yale astronomers Grant Tremblay and Meredith Powell are part of the first research team to document a “changing look”
    quasar through a full cycle from dim to bright to dim again.

    Quasars are the extremely bright cores found in some galaxies, powered by supermassive black holes.
    Their brightness is believed to come from the hot material that falls into the black hole, a process called accretion.

    “Thirty years ago this supermassive black hole very dramatically brightened, becoming a Type 1 quasar,” Tremblay said.
    “We discovered this year that it has now dimmed again, making it the first such object to go ‘there and back again.’”

    Two research studies of the object — galaxy Markarian 1018 — will appear in the journal Astronomy & Astrophysics.
    A portion of the data used in the studies comes from the Close AGN Reference Survey (CARS), a sampling of 40 nearby
    Active Galactic Nuclei. Yale is a founding member institution of the survey.

    VIRGO
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    1 odpověď+6
    PECKA!!!! Po úspěchu observatoří LIGO se NASA rozhodla opět připojit k projektu LISA!
    NASA moves to rejoin sped-up gravitational wave mission | Science | AAAS
    http://www.sciencemag.org/news/2016/09/nasa-moves-rejoin-sped-gravitational-wave-mission

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    Beginning of the end | Rosetta - ESA's comet chaser
    http://blogs.esa.int/rosetta/2016/09/16/beginning-of-the-end/

    Rosetta: the end is in sight
    https://www.youtube.com/watch?v=UobzGZH2VnE


    2 WEEKS TO GO! Until Rosetta crash-lands on Comet 67P... & joins Philae...

    VIRGO
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    Black Holes Are Nothing But Holograms, New Study Finds
    http://sci-techuniverse.blogspot.com/2016/09/black-holes-are-nothing-but-holograms.html

    A group of physicists led by Daniele Pranzetti from the Max Planck Institute for Theoretical Physics in Germany has now presented
    a new approximation for the amount of entropy existing in a black hole, and their calculations support this situation.

    The physicists were concentrating on the entropy - a physical property that encrypts how ordered, or disordered, something really is.
    According to Stephen Hawking, the entropy of a black hole must be relative to its area, but not its volume, and this notion is what
    encouraged the first thoughts about the probability of holographic black holes.

    Joanne Kennel explains for The Science Explorer, said "Although there is some consensus in the scientific community that black holes
    must have entropy or their existence would violate the second law of thermodynamics, no agreement has been reached about the origin
    of this entropy, or how to calculate its value,"
    VIRGO
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    Some Ancient Mars Lakes Came Long After Others
    http://www.nasa.gov/feature/jpl/some-ancient-mars-lakes-came-long-after-others

    Lakes and snowmelt-fed streams on Mars formed much later than previously thought possible,
    according to new findings using data primarily from NASA's Mars Reconnaissance Orbiter.

    The recently discovered lakes and streams appeared roughly a billion years after a well-documented, earlier era of wet conditions on ancient Mars.
    These results provide insight into the climate history of the Red Planet and suggest the surface conditions at this later time may also have been
    suitable for microbial life.

    VIRGO
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    Four Days at Saturn
    https://www.youtube.com/watch?v=gqXcXNUu1lg


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    První záběr startrackerů - navigačních kamer OSIRIS-REx!
    https://www.nasa.gov/feature/goddard/2016/osiris-rex-mission-status-report-sept-15

    VIRGO
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    The Geomagnetic Blitz of September 1941 - Eos
    https://eos.org/features/the-geomagnetic-blitz-of-september-1941

    Seventy-five years ago next week, a massive geomagnetic storm disrupted electrical power,
    interrupted radio broadcasts, and illuminated the night sky in a World War II battle theater.

    VIRGO
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    Kamikaze galaxy explodes after diving into the Milky Way  | New Scientist
    https://www.newscientist.com/...le/2106019-kamikaze-galaxy-explodes-after-diving-into-the-milky-way/

    At least 50 galaxies orbit our own. The Hercules dwarf is currently 460,000 light years from Earth,
    nearly three times farther than the Milky Way’s brightest satellite galaxy, the Large Magellanic Cloud.

    But Hercules’s stars spread over a great expanse of space, which suggests the Milky Way’s gravitational
    pull has yanked them away from one another.

    Now Andreas Küpper and Kathryn Johnston at Columbia University in New York and their colleagues have
    used the observed positions and velocities of the galaxy’s stars to deduce its path through space.

    “It’s plunging in from a really large distance to a really close distance,” Johnston says.

    The astronomers calculate that, at its farthest, the dim galaxy voyages 600,000 light years from
    the Milky Way’s centre. At its closest, though, it’s just 16,000 light years out.

    “That’s extreme,” Küpper says. It’s closer than any other satellite galaxy is known to come. It’s even
    closer than we are – the sun is 27,000 light years from the galactic centre.

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    Arctic Sea Ice Annual Minimum Ties Second Lowest on Record
    http://www.nasa.gov/feature/goddard/2016/arctic-sea-ice-annual-minimum-ties-second-lowest-on-record

    The sea ice cover of the Arctic Ocean and surrounding seas helps regulate the planet’s temperature,
    influences the circulation of the atmosphere and ocean, and impacts Arctic communities and ecosystems.
    Arctic sea ice shrinks every year during the spring and summer until it reaches its minimum yearly extent.
    Sea ice regrows during the frigid fall and winter months, when the sun is below the horizon in the Arctic.

    Sea Ice Minimum 2016
    https://www.youtube.com/watch?v=GVJ9DfVhAYw
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    How Certain Are We Of The Universe's 'Big Freeze' Fate?
    http://www.forbes.com/...016/09/15/how-certain-are-we-of-the-universes-big-freeze-fate/#3f34c1ae12cf

    VIRGO
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    Gaia's new star map will also reveal asteroids and dark matter | New Scientist
    https://www.newscientist.com/...06053-gaias-new-star-map-will-also-reveal-asteroids-and-dark-matter/
    Astronomers will also use the positions of visible stars to map invisible dark matter. The mysterious stuff makes up nearly
    85 per cent of the matter in the universe, and exerts a gravitational pull on all stars, bending their paths as they traverse
    their home galaxy. Any deviations that can’t be explained by the visible matter will be the handiwork of dark matter.

    “Our current paradigm says that dark matter should be lumpy on small scales,” says David Spergel at Princeton University.
    This paradigm is based on the theory that dark matter is composed of massive slow particles that mostly interact through
    the force of gravity. Such lethargic particles will hang around in clusters for a while. But if we find that dark matter
    is smooth rather than lumpy, astronomers might have to come up with alternative explanations.


    Cat’s Eye Nebula: 3000 light years away, as seen by Hubble and Gaia
    NASA/ESA/HEIC/The Hubble Heritage Team/STScI/AURA (background image); ESA/Gaia/DPAC/UB/IEEC (blue points)

    VIRGO
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    Black Hole Hidden Within Its Own Exhaust
    http://www.almaobservatory.org/...-room/press-releases/1036-black-hole-hidden-within-its-own-exhaust

    Supermassive black holes, millions to billions of times the mass of our Sun, are found at the centers of galaxies. Many of these galactic behemoths
    are hidden within a thick doughnut-shape ring of dust and gas known as a torus. Previous observations suggest these cloaking, tire-like structures
    are formed from the native material found near the center of a galaxy.

    New data from the Atacama Large Millimeter/submillimeter Array (ALMA), however, reveal that the black hole at the center of a galaxy named NGC 1068
    is actually the source of its own dusty torus of dust and gas, forged from material flung out of the black hole’s accretion disk.

    This newly discovered cosmic fountain of cold gas and dust could reshape our understanding of how black holes impact their host galaxy and
    potentially the intergalactic medium.

    VIRGO
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    Mount St. Helens: Back from the Dead • Volcanic Eruption
    https://volcanic-eruption.com/mount-st-helens-back-from-the-dead/

    PBS NOVA Mount St. Helens: Back from the Dead (2010)
    https://www.youtube.com/watch?v=fuwVykebcMg
    VIRGO
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    This 1999 photo shows the fourth 8.2-m VLT Zerodur mirror during the final phase of polishing at REOSC.
    http://www.eso.org/public/images/eso9952a/

    VIRGO
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    Hubble Takes Close-up Look at Disintegrating Comet
    http://www.nasa.gov/feature/goddard/2016/hubble-takes-close-up-look-at-disintegrating-comet

    NASA’s Hubble Space Telescope has captured one of the sharpest, most detailed observations of a comet breaking apart,
    which occurred 67 million miles from Earth.

    In a series of images taken over a three-day span in January 2016, Hubble revealed 25 building-size blocks made of
    a mixture of ice and dust that are drifting away from the comet at a leisurely pace, about the walking speed of an adult.

    The observations suggest that the roughly 4.5-billion-year-old comet, named 332P/Ikeya-Murakami, or Comet 332P, may be
    spinning so fast that material is ejected from its surface. The resulting debris is now scattered along a 3,000-mile-long
    trail, larger than the width of the continental U.S.

    These observations provide insight into the volatile behavior of comets as they approach the sun and begin to vaporize,
    unleashing dynamical forces. Comet 332P was 150 million miles from the sun, slightly beyond the orbit of Mars,
    when Hubble spotted the breakup.

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    Starving Black Hole Returns Brilliant Galaxy to the Shadows | ESO
    http://www.eso.org/public/news/eso1631/

    The mystery of a rare change in the behaviour of a supermassive black hole at the centre of a distant galaxy has been solved by an international
    team of astronomers using ESO’s Very Large Telescope along with the NASA/ESA Hubble Space Telescope and NASA’s Chandra X-ray Observatory. It
    seems that the black hole has fallen on hard times and is no longer being fed enough fuel to make its surroundings shine.

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    Bayesian View of Galaxy Evolution | Galaxy Zoo
    https://blog.galaxyzoo.org/2016/09/14/bayesian-view-of-galaxy-evolution/

    By Peter McGill

    The Universe is pretty huge, and to understand it we need to collect vast amounts of data. The Hubble Telescope is just one of many telescopes
    collecting data from the Universe. Hubble alone produces 17.5 GB of raw science data each week. That means since its launch to low earth orbit
    in April 1990, it’s collected roughly a block of data equivalent in size to 6 million mp3 songs! With the launch of NASA’s James Webb Telescope
    just around the corner, the amount of raw data we can collect from the Universe is going to escalate dramatically. In order to decipher what
    this data is telling us about the Universe we need to use sophisticated statistical techniques. In this post I want to talk a bit about
    a particular technique I’ve been using called a Markov-Chain-Monte-Carlo (MCMC) simulation to learn about galaxy evolution.
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