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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Mars rover spots clouds shaped by gravity waves | Science | AAAS
    http://www.sciencemag.org/news/2017/03/mars-rover-spots-clouds-shaped-gravity-waves

    NASA’s Curiosity rover usually keeps its instruments firmly focused on Mars’s ground, zapping grit with its laser or drilling
    cores in bedrock. But every few days, the SUV-sized robot, like any good dreamer, shifts its sights upward to the clouds.

    Well into its fifth year, the rover has now shot more than 500 movies of the clouds above it, including the first ground-based
    view of martian clouds shaped by gravity waves, researchers reported here this week at the Lunar and Planetary Science Conference.
    (Gravity waves, common atmospheric ripples on Earth that result from air trying to regain its vertical balance, should not be
    confused with gravitational waves, cosmological ripples in spacetime.) The shots are the best record made so far of a mysterious
    recurring belt of equatorial clouds known to influence the martian climate.



    VIRGO
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    Four new short-period giant planets discovered
    https://phys.org/news/2017-07-short-period-giant-planets.html

    Astronomers have detected four new giant exoplanets as part of the Hungarian-made Automated Telescope Network-South (HATSouth) exoplanet survey.
    The newly found alien worlds are about the size of Jupiter, but less massive. They transit moderately bright stars and have short orbital periods.
    The findings were presented July 22 in a paper published on arXiv.org.

    HATSouth is a network of six astrograph telescope systems located in South America, Africa, and Australia. These telescopes are designed to detect
    transiting extrasolar planets in orbit around relatively bright stars visible from the Southern hemisphere. Since its launch in 2009, the network
    has already detected dozens of transiting exoplanets.

    Now, the list of planets detected by HATSouth has expanded. In a recent paper, a team of researchers led by Rafael Brahm of the Pontifical Catholic
    University of Chile in Santiago presents the discovery of four new planets, HATS-43b, HATS-44b, HATS-45b, and HATS-46b. The planetary nature of
    transiting signals detected by HATSouth was confirmed by follow-up spectroscopic and photometric observations using various instruments, including
    the Las Cumbres Observatory Global Telescope (LCOGT) network at the Cerro Tololo International Observatory (CTIO) in Chile.

    This extensive observational campaign that led to the discovery of four new alien worlds was carried out from December 2009 to October 2016.

    VIRGO
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    To bylo "o fous", a navíc jsme to úplně prospali... :)

    Asteroid *2017 OO1* discovered. It missed the Earth really close (but still safe!) on Jul 21 at 02:27 UT.
    Dist: 0.33 LD (0.32 LD from Earth surface). Size: 25-78 m. Closer report comming.



    IAU Minor Planet Center
    http://www.minorplanetcenter.net/db_search/show_object?object_id=2017+OO1

    A newly discovered asteroid designated 2017 OO1 flew past Earth at a very close distance of 0.33 LD
    (~125 720 km / 78 740 miles) at 02:27 UTC on July 21, 2017. It was discovered 2 days after its closest approach.

    This is the 21st known near-Earth asteroid to flyby Earth within 1 lunar distance since the start of the year.
    The last time one flew past us within that distance was on May 4. Asteroid 2017 OO1 belongs to the Aten group
    of asteroids and was first observed at ATLAS-MLO, Mauna Loa, Hawaii on July 23, 2017.

    Its estimated diameter is between 35 to 77 m (115 - 252.6 feet) and it flew past Earth at a speed (relative to
    the Earth) of 10.36 km/s.

    Asteroid 2017 OO1 flew past Earth at a very close distance of 0.33 LD
    https://watchers.news/2017/07/25/asteroid-2017-oo1/

    VIRGO
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    https://www.nasa.gov/feature/jpl/large-distant-comets-more-common-than-previously-thought

    Comets that take more than 200 years to make one revolution around the Sun are notoriously difficult to study. Because they spend most of their time far from our area
    of the solar system, many "long-period comets" will never approach the Sun in a person's lifetime. In fact, those that travel inward from the Oort Cloud - a group of
    icy bodies beginning roughly 186 billion miles (300 billion kilometers) away from the Sun - can have periods of thousands or even millions of years.

    NASA's WISE spacecraft, scanning the entire sky at infrared wavelengths, has delivered new insights about these distant wanderers. Scientists found that there are about
    seven times more long-period comets measuring at least 0.6 miles (1 kilometer) across than had been predicted previously. They also found that long-period comets are on
    average up to twice as large as "Jupiter family comets," whose orbits are shaped by Jupiter’s gravity and have periods of less than 20 years.

    VIRGO
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    https://www.nasa.gov/feature/goddard/2017/chasing-the-total-solar-eclipse-from-nasa-s-wb-57f-jets

    For most viewers, the Aug. 21, 2017, total solar eclipse will last less than two and half minutes. But for one team of NASA-funded
    scientists, the eclipse will last over seven minutes. Their secret? Following the shadow of the Moon in two retrofitted WB-57F jet planes.

    Amir Caspi of the Southwest Research Institute in Boulder, Colorado, and his team will use two of NASA’s WB-57F research jets to chase
    the darkness across America on Aug. 21. Taking observations from twin telescopes mounted on the noses of the planes, Caspi will ­­­­­capture
    the clearest images of the Sun’s outer atmosphere — the corona — to date and the first-ever thermal images of Mercury, revealing how
    temperature varies across the planet’s surface.

    NASA Jets Chase The Total Solar Eclipse
    https://www.youtube.com/watch?v=R0GNqlGNZkI
    VIRGO
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    A new long period comet has been discovered: Comet C/2017 O1

    http://www.minorplanetcenter.net/db_search/show_object?object_id=C/2017%20O1



    COMET C/2017 O1 taken by Ernesto Guido on July 23, 2017 @ remotely from Australia, Siding Spring.





    New Comet C/2017 O1 ASSSN

    Comet 2017 ASASSN1 (not a formal name yet) imaged by Nidia Morell with the Magellan 6.5-m telescope, image processed by Subo Dong.



    C/2017 O1 ASSSN taken by rolando ligustri on July 22, 2017 @ from Australia SSO, Itelescope.net

    VIRGO
    VIRGO --- ---
    Cassini: The Grand Finale: Cassini's First D-Ring Crossing
    https://saturn.jpl.nasa.gov/resources/7714/?category=videos

    The sounds and colorful spectrogram in this still image and video represent data collected by the Radio and Plasma
    Wave Science, or RPWS, instrument on NASA's Cassini spacecraft, as it crossed through Saturn's D ring on May 28, 2017.

    VIRGO
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    VIRGO
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    https://www.nasa.gov/image-feature/jpl/pia21339/ring-bow

    This view looks toward the sunlit side of the rings from about 19 degrees above the ringplane.
    The image was taken in visible light with the Cassini spacecraft wide-angle camera on April 10, 2017.

    The view was obtained at a distance of approximately 1.1 million kilometers from Saturn and at
    a sun-Saturn-spacecraft, or phase, angle of 128 degrees. Image scale is 69 kilometers per pixel.

    VIRGO
    VIRGO --- ---
    Discovery of a rare quadruple gravitational lens candidate with Pan-STARRS
    https://phys.org/news/2017-07-discovery-rare-quadruple-gravitational-lens.html

    Astronomers from the United States Naval Observatory (USNO) in conjunction with colleagues from the University of California, Davis, and
    Rutgers University have discovered the first quadruple gravitational lens candidate within data from the Panoramic Survey Telescope and Rapid

    Response System (Pan-STARRS) using a combination of all-sky survey data from the USNO Robotic Astrometric Telescope (URAT) and the Wide-field
    Infrared Survey Explorer (WISE).

    USNO graduate student George Nelson, who was performing a URAT variability study of the brightest quasars identified by USNO astronomers using
    WISE colors, discovered the lens while investigating the optical properties of a bright quasar sample. The paper describing this serendipitous
    discovery has been accepted for publication in the Astrophysical Journal.

    A preprint of the paper may be found at arxiv.org/abs/1705.08359. A paper confirming the discovery by a separate team of astronomers using the
    Keck Cosmic Web Imager has been submitted to the Astrophysical Journal Letters. A preprint of this paper may be found at arxiv.org/abs/1707.05873.

    VIRGO
    VIRGO --- ---
    Cosmologists produce new maps of dark matter dynamics | UoP News
    http://uopnews.port.ac.uk/2017/07/25/cosmologists-produce-new-maps-of-dark-matter-dynamics/

    New maps of dark matter dynamics in the Universe have been produced by a team of international cosmologists.

    Using advanced computer modelling techniques, the research team has translated the distribution of galaxies into detailed maps of matter
    streams and velocities for the first time. The research was carried out by leading cosmologists from the UK, France and Germany.

    The researchers used legacy survey data obtained during 2000 – 2008 from the Sloan Digital Sky Survey (SDSS), a major three-dimensional
    survey of the Universe. The survey has deep multi-colour images of one fifth of the sky and spectra for more than 900,000 galaxies.

    The new dark matter maps cover the Northern Sky up to a distance of 600 megaparsecs, which is the equivalent of looking back about two
    billion years. The researchers used a set of phase-space analysis tools and built on research from 2015, which reconstructed the initial
    conditions of the nearby Universe.

    VIRGO
    VIRGO --- ---
    Why Cosmic Inflation Is Here To Stay
    http://nautil.us/issue/48/chaos/the-inflated-debate-over-cosmic-inflation

    Why the majority of physicists are on one side of a recent exchange of letters.

    VIRGO
    VIRGO --- ---
    The Story of a Boring Encounter with a Black Hole
    http://aasnova.org/2017/07/24/the-story-of-a-boring-encounter-with-a-black-hole/

    Remember the excitement three years ago before the gas cloud G2’s encounter with the supermassive black hole at the center of our galaxy, Sgr A*?
    Did you notice that not much was said about it after the fact? That’s because not much happened — and a new study suggests that this isn’t surprising.

    G2, an object initially thought to be a gas cloud, was expected to make its closest approach to the 4.6-million-solar-mass Sgr A* in 2014. At the pericenter
    of its orbit, G2 was predicted to pass as close as 36 light-hours from the black hole. This close brush with such a massive black hole was predicted to tear
    G2 apart, causing much of its material to accrete onto Sgr A*. It was thought that this process would temporarily increase the accretion rate onto the black
    hole relative to its normal background accretion rate, causing Sgr A*’s luminosity to increase for a time.

    Instead, Sgr A* showed a distinct lack of fireworks, with very minimal change to its brightness after G2’s closest approach. This “cosmic fizzle” has raised
    questions about the nature of G2: was it really a gas cloud? What else might it have been instead? Now, a team of scientists led by Brian Morsony (University
    of Maryland and University of Wisconsin-Madison) have run a series of simulations of the encounter to try to address these questions.

    VIRGO
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    VIRGO: These telescopes observed Barnard's Star and Ross 128 last week.

    VIRGO
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    PHL: The Weird! Signal by Abel Mendez
    The Weird! Signal - Planetary Habitability Laboratory @ UPR Arecibo
    http://phl.upr.edu/press-releases/theweirdsignal

    VIRGO
    VIRGO --- ---
    Dark matter is likely ‘cold,’ not ‘fuzzy,’ scientists report after new simulations | UW News
    http://www.washington.edu/...atter-is-likely-cold-not-fuzzy-scientists-report-after-new-simulations/

    Dark matter is the aptly named unseen material that makes up the bulk of matter in our universe. But what dark matter is made of is a matter of debate.

    Scientists have never directly detected dark matter. But over decades, they have proposed a variety of theories about what type of material — from new
    particles to primordial black holes — could comprise dark matter and explain its many effects on normal matter. In a paper published July 20 in the journal
    Physical Review Letters, an international team of cosmologists uses data from the intergalactic medium — the vast, largely empty space between galaxies —
    to narrow down what dark matter could be.

    The team’s findings cast doubt on a relatively new theory called “fuzzy dark matter,” and instead lend credence to a different model called “cold dark matter.”
    Their results could inform ongoing efforts to detect dark matter directly, especially if researchers have a clear idea of what sorts of properties they should
    be seeking.

    VIRGO
    VIRGO --- ---
    Mapping Dark Mattersu201727 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201727

    Galaxies generally reside at the centers of vast clumps of dark matter called haloes because they surround the clusters of galaxies. Gravitational lensing
    of more distant galaxies by dark matter haloes offers a particularly unique and powerful probe of the detailed distribution of dark matter. So-called strong
    gravitational lensing creates highly distorted, magnified and occasionally multiple images of a single source; so-called weak lensing results in modestly yet
    systematically deformed shapes of background galaxies that can also provide robust constraints on the distribution of dark matter within the clusters.

    CfA astronomers Annalisa Pillepich and Lars Hernquist and their colleagues compared gravitationally distorted Hubble images of the galaxy cluster Abell 2744
    and two other clusters with the results of computer simulations of dark matter haloes. They found, in agreement with key predictions in the conventional dark
    matter picture, that the detailed galaxy substructures depend on the dark matter halo distribution, and that the total mass and the light trace each other.
    They also found a few discrepancies: the radial distribution of the dark matter is different from that predicted by the simulations, and the effects of tidal
    stripping and friction in galaxies are smaller than expected, but they suggest these issues might be resolved with more precise simulations. Overall, however,
    the standard model of dark matter does an excellent and reassuring job of describing galaxy clustering.

    VIRGO
    VIRGO --- ---
    Seeing double | ESO Australia
    http://www.eso.org/public/australia/images/potw1730a/

    Approximately 95 million light-years away, in the southern constellation of Octans (The Octant), lies NGC 7098 — an intriguing spiral galaxy with numerous
    sets of double features. The first of NGC 7098’s double features is a duo of distinct ring-like structures that loop around the galaxy’s hazy heart. These
    are NGC 7098’s spiral arms, which have wound themselves around the galaxy’s luminous core. This central region hosts a second double feature: a double bar.

    VIRGO
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    Hubble’s Hunting Dog Galaxy
    https://www.nasa.gov/image-feature/goddard/2017/hubbles-hunting-dog-galaxy

    Tucked away in the small northern constellation of Canes Venatici (The Hunting Dogs) is the galaxy NGC 4242, shown here as seen by the NASA/ESA
    Hubble Space Telescope. The galaxy lies some 30 million light-years from us. At this distance from Earth, actually not all that far on a cosmic scale,
    NGC 4242 is visible to anyone armed with even a basic telescope, as British astronomer William Herschel found when he discovered the galaxy in 1788.

    VIRGO
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    Study teams comb through NASA’s wish list for new telescope – Spaceflight Now
    https://spaceflightnow.com/2017/07/21/study-teams-comb-through-nasas-wish-list-for-a-new-telescope/

    Scientists outlining four concepts for a powerful new space telescope that could launch in the 2030s this week said improvements in optics, detectors and access to huge new
    rockets like NASA’s Space Launch System could revolutionize the way astronomers observe potentially habitable planets, black holes, and the earliest galaxies in the universe.

    It is likely NASA will only be able to afford one of the four proposed flagship observatories, and the space agency will take the advice of an independent review by the National
    Research Council in 2020 on which type of telescope should receive highest priority.

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