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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
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    A map that fills a 500-million year gap in Earth's history
    https://theconversation.com/a-map-that-fills-a-500-million-year-gap-in-earths-history-79838

    Earth is estimated to be around 4.5 billion years old, with life first appearing around 3 billion years ago.

    To unravel this incredible history, scientists use a range of different techniques to determine when and where continents moved,
    how life evolved, how climate changed over time, when our oceans rose and fell, and how land was shaped. Tectonic plates – the huge,
    constantly moving slabs of rock that make up the outermost layer of the Earth, the crust – are central to all these studies.

    Along with our colleagues, we have published the first whole-Earth plate tectonic map of half a billion years of Earth history,
    from 1,000 million years ago to 520 million years ago.

    A map that fills a 500-million year gap in Earth's history
    https://www.youtube.com/watch?v=77NKvC4nkvY
    VIRGO
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    VIRGO:

    The mystique of Barnard's Star | Astronomy Essentials | EarthSky
    http://earthsky.org/astronomy-essentials/barnards-star-closest-stars-famous-stars

    Although very common, red dwarfs like Barnard’s Star are typically dim. Thus they are notoriously faint and hard to study. In fact, not a single red dwarf
    can be seen with the unaided human eye. But because Barnard’s Star is relatively close and bright, it has become a go-to model for all things red dwarf.

    At nearly six light-years’ distance, Barnard’s Star is often cited as the second-closest star to our sun (and Earth). This is true only if you consider
    the triple star system Alpha Centauri as one star.

    Proxima Centauri, the smallest and faintest of Alpha Centauri’s three components, is the closest known star to the sun at just 4.24 light years away.
    It, too, is a red dwarf. So Barnard’s Star is only the second-closest red dwarf star. It is perhaps more important for astronomical purposes, though,
    because Proxima is four times fainter and thus harder to study.

    VIRGO
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    Syfy - Bad Astronomy | The planets, like grains of sand
    http://www.syfy.com/syfywire/the-planets-like-grains-of-sand

    Statistically speaking, for every planet Kepler finds, there are a million more in the galaxy waiting to be discovered.
    VIRGO
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    VIRGO
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    Success of Gravity-Wave Satellite Paves Way for 3-Craft Mission - Scientific American
    https://www.scientificamerican.com/...ccess-of-gravity-wave-satellite-paves-way-for-3-craft-mission/

    Technology far exceeded expectations in LISA Pathfinder test

    VIRGO
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    https://www.nasa.gov/image-feature/jpl/pia21763/the-niagara-falls-of-mars

    Various researchers are often pre-occupied with the quest for flowing water on Mars. However, this image from NASA's Mars Reconnaissance
    Orbiter (MRO), shows one of the many examples from Mars where lava (when it was molten) behaved in a similar fashion to liquid water.

    VIRGO
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    The stable retrograde orbit of the Bee-Zed asteroid explained
    https://phys.org/news/2017-06-stable-retrograde-orbit-bee-zed-asteroid.html

    In our solar system, an asteroid orbits the sun in the opposite direction to the planets. Asteroid 2015 BZ509, also known as Bee-Zed, takes 12 years to
    make one complete orbit around the sun. This is the same orbital period as that of Jupiter, which shares its orbit but moves in the opposite direction.

    RThe asteroid with the retrograde co-orbit was identified by Helena Morais, a professor at São Paulo State University's Institute of Geosciences & Exact
    Sciences (IGCE-UNESP). Morais had predicted the discovery two years earlier, and has published his findings in Nature.

    "It's good to have confirmation," Morais said. "I was sure retrograde co-orbits existed. We've known about this asteroid since 2015, but the orbit hadn't
    been clearly determined, and it wasn't possible to confirm the co-orbital configuration. Now it's been confirmed after more observations that reduced the
    number of errors in the orbital parameters. So, we're sure the asteroid is retrograde, co-orbital and stable."

    In partnership with Fathi Namouni at the Côte d'Azur Observatory in France, Morais developed a general theory on retrograde co-orbitals and retrograde
    orbital resonance.

    VIRGO
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    The proper motion of Barnard’s Star captured over 9 years - 2007 to 2015.

    VIRGO
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    Makemake dostala pozorovací čas na HST!!
    Alex Parker on Twitter: "We get to study the moons of dwarf planets Makemake & 2007 OR10 with @NASAHubble! Orbits will reveal masses & densities for the first time. https://t.co/qrTFlfzDdZ"
    https://twitter.com/Alex_Parker/status/879505168701718528
    NEBULA
    NEBULA --- ---
    VIRGO: chápu :)
    VIRGO
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    Galaxy NGC 1132 has a disturbed hot halo, study finds
    https://phys.org/news/2017-06-galaxy-ngc-disturbed-hot-halo.html

    A new study recently published on arXiv.org reveals that the fossil group galaxy NGC 1132 (also known as UGC 2359) has a disturbed and asymmetrical hot halo.
    The findings provide new insights into the formation and evolution of this galaxy and could improve our understanding of fossil groups in the universe.

    Located some 318 million light years away from the Earth, NGC 1132 is a well-known fossil galaxy group. The so-called "fossil group" is an isolated elliptical
    galaxy embedded in an extended halo of X-ray emitting gas the size of a galaxy group. Such groups are believed to be the end result of galaxy merging within
    a normal galaxy group, leaving behind the X-ray halo of the progenitor group.

    VIRGO
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    Groundbreaking discovery confirms existence of orbiting supermassive black holes: UNM Newsroom
    http://news.unm.edu/...undbreaking-discovery-confirms-existence-of-orbiting-supermassive-black-holes

    For the first time ever, astronomers at The University of New Mexico say they’ve been able to observe and measure the orbital motion
    between two supermassive black holes hundreds of millions of light years from Earth – a discovery more than a decade in the making.

    UNM Department of Physics & Astronomy graduate student Karishma Bansal is the first-author on the paper, ‘Constraining the Orbit
    of the Supermassive Black Hole Binary 0402+379’, recently published in The Astrophysical Journal. She, along with UNM Professor Greg
    Taylor and colleagues at Stanford, the U.S. Naval Observatory and the Gemini Observatory, have been studying the interaction between
    these black holes for 12 years.

    “For a long time, we’ve been looking into space to try and find a pair of these supermassive black holes orbiting as a result of two
    galaxies merging,” said Taylor. “Even though we’ve theorized that this should be happening, nobody had ever seen it until now.”
    VIRGO
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    NEBULA: Já teď nestíhám nic kromě práce, která se po té pauze nakupila. Hrůza...
    NEBULA
    NEBULA --- ---
    VIRGO: půjdeš se tam podívat?
    VIRGO
    VIRGO --- ---
    Discoveries Fuel Fight Over Universe’s First Light | Quanta Magazine
    https://www.quantamagazine.org/discoveries-fuel-fight-over-universes-first-light-20170519/

    A series of observations at the very edge of the universe has reignited a debate over what lifted the primordial cosmic fog.

    Not long after the Big Bang, all went dark. The hydrogen gas that pervaded the early universe would have snuffed out the light of the universe’s
    first stars and galaxies. For hundreds of millions of years, even a galaxy’s worth of stars — or unthinkably bright beacons such as those created
    by supermassive black holes — would have been rendered all but invisible.

    Eventually this fog burned off as high-energy ultraviolet light broke the atoms apart in a process called reionization. But the questions of exactly
    how this happened — which celestial objects powered the process and how many of them were needed — have consumed astronomers for decades.

    Now, in a series of studies, researchers have looked further into the early universe than ever before. They’ve used galaxies and dark matter as a giant
    cosmic lens to see some of the earliest galaxies known, illuminating how these galaxies could have dissipated the cosmic fog. In addition, an international
    team of astronomers has found dozens of supermassive black holes — each with the mass of millions of suns — lighting up the early universe. Another team
    has found evidence that supermassive black holes existed hundreds of millions of years before anyone thought possible. The new discoveries should make
    clear just how much black holes contributed to the reionization of the universe, even as they’ve opened up questions as to how such supermassive
    black holes were able to form so early in the universe’s history.

    VIRGO
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    Jiří Grygar - Jsme ve vesmíru sami? (KS ČAS 5.6.2017)
    https://www.youtube.com/watch?v=M6Vh-NwBT9o
    VIRGO
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    Meteorite hits White Nile, Sudan, large fragments found
    https://watchers.news/2017/06/26/sudan-meteorite-white-nile-june-2017/

    Sudanese authorities said Sunday, June 25, 2017, they have recovered fragments of meteorites which struck a remote area
    of the state of White Nile in the south of the state at dawn on Wednesday, June 21. Eyewitness reports mention loud sound
    and a bright light that illuminated the night sky of several regions in the state. The meteorite matter is reportedly
    the size of a small car.

    VIRGO
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    The Shapes of Galaxiessu201723 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201723

    Since Edwin Hubble proposed his galaxy classification scheme in 1926, numerous studies have investigated the physical mechanisms responsible
    for the shapes of spiral and elliptical galaxies. Because the processes are complex, however, studies frequently rely on computer simulations
    as their main tool. The discs of galaxies are believed to form through the collapse of gas which acquires its initial spin in the early Universe.
    During their subsequent evolution, galaxies undergo a wide range of phenomena, from the accretion of matter -- or its outflow -- to mergers with
    other galaxies, all of which modify the disk’s spin and angular momentum.

    Astronomers think that spiral galaxies with the largest galactic discs formed preferentially in protogalaxies with the highest angular momentum,
    although early attempts to verify this prediction using computer simulations failed. (More recently, simulations have been able to verify this
    trend.) Elliptical galaxies, on the other hand, are believed to be the remnants of repeated galaxy mergers, but their shapes depend on many details
    like the galaxies' masses, gas content, and the collision parameters. As a result, these mergers need to be considered over a cumulative,
    cosmological context with large numbers of examples to evaluate their development from a statistical perspective.

    CfA astronomers Vicente Rodriguez-Gomez, Annalisa Pillepich and Lars Hernquist led a team that analyzed the morphologies of about eighteen thousand
    galaxies in the Illustris computer simulation. Both disc and spheroidal galaxies arise naturally in this simulation. They find that massive merging
    galaxies develop into spirals or spheroidal shapes depending on their gas content (as expected, since the star formation activity depends crucially
    on the gas). Unexpectedly, they find that for lower mass galaxies -- roughly the mass of the Milky Way or smaller -- mergers do not seem to play
    a significant role in determining the morphology. The reason appears to be that in higher mass mergers a galaxy accretes many more stars from
    the partner, and this plays the a critical role. Their significant conclusion is that only in massive galaxies are mergers the dominant factor
    in shaping the system.

    VIRGO
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    https://www.nasa.gov/image-feature/jpl/pia21334/saturnian-dawn

    NASA's Cassini spacecraft peers toward a sliver of Saturn's sunlit atmosphere while the icy rings stretch across the foreground as a dark band.

    This view looks toward the unilluminated side of the rings from about 7 degrees below the ring plane. The image was taken in green light with
    the Cassini spacecraft wide-angle camera on March 31, 2017.

    The view was obtained at a distance of approximately 620,000 miles (1 million kilometers) from Saturn. Image scale is 61 kilometers per pixel.

    DRAGON
    DRAGON --- ---
    VIRGO: uz vidim, jak si za par let budeme rikat, jak neco tak rozmazanyho mohlo byt povazovano za 'image' a budem se tomu smat jako fotkam Mesice z dob objevu telefotografickejch zarizeni :)
    Kliknutím sem můžete změnit nastavení reklam