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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
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    A New Bound on Axionssu201802 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201802

    CfA astronomer Paul Nulsen and his colleagues used a novel method to investigate the nature of axions. Quantum mechanics constrain axions, if they exist, to interact with light in the presence of a magnetic field.
    As they propagate along a strong field, axions and photons should transmute from one to the other other in an oscillatory manner. Because the strength of any possible effect depends in part on the energy of the photons,
    the astronomers used the Chandra X-ray Observatory to monitor bright X-ray emission from galaxies. They observed X-rays from the nucleus of the galaxy M87, which is known to have strong magnetic fields, and which (at
    a distance of only fifty-three million light-years) is close enough to enable precise measurements of variations in the X-ray flux. Moreover, M87 lies in a cluster of galaxies, the Virgo cluster, which should insure
    the magnetic fields extend over very large scales and also facilitate the interpretation. Not least, M87 has been carefully studied for decades and its properties are relatively well known.

    The search did not find the signature of axions. It does, however, set an important new limit on the strength of the coupling between axions and photons, and is able to rule out a substantial fraction of the possible
    future experiments that might be undertaken to detect axions. The scientists note that their research highlights the power of X-ray astronomy to probe some basic issues in particle physics, and point to complementary
    research activities that can be undertaken on other bright X-ray emitting galaxies.
    VIRGO
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    Update on an Interstellar Asteroid
    http://aasnova.org/2018/01/19/update-on-an-interstellar-asteroid/

    Are we sure ‘Oumuamua didn’t originate in our solar system and get scattered into a weird orbit? Jason Wright (The Pennsylvania State University)
    demonstrates via a series of calculations that no known solar system body could have scattered ‘Oumuamua onto its current orbit — nor could any as
    yet unknown object bound to our solar system.

    Eric Mamajek (Caltech and University of Rochester) shows that the kinematics of ‘Oumuamua are consistent with what we might expect of interstellar
    field objects, though he argues that its kinematics suggest it’s unlikely to have originated from many of the nearest stellar systems.

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    https://www.nasa.gov/feature/jpl/asteroid-2002-aj129-to-fly-safely-past-earth-february-4

    Asteroid 2002 AJ129 will make a close approach to Earth on Feb. 4, 2018 at 1:30 p.m. PST (4:30 p.m. EST / 21:30 UTC). At the time of closest approach,
    the asteroid will be no closer than 10 times the distance between Earth and the Moon (about 2.6 million miles, or 4.2 million kilometers).

    2002 AJ129 is an intermediate-sized near-Earth asteroid, somewhere between 0.3 miles (0.5 kilometers) and 0.75 miles (1.2 kilometers) across. It was discovered
    on Jan. 15, 2002, by the former NASA-sponsored Near Earth Asteroid Tracking project at the Maui Space Surveillance Site on Haleakala, Hawaii. The asteroid’s
    velocity at the time of closest approach, 76,000 mph (34 kilometers per second), is higher than the majority of near-Earth objects during an Earth flyby.
    The high flyby velocity is a result of the asteroid’s orbit, which approaches very close to the Sun -- 11 million miles (18 million kilometers). Although asteroid
    2002 AJ129 is categorized as a Potentially Hazardous Asteroid (PHA), it does not pose an actual threat of colliding with our planet for the foreseeable future.

    VIRGO
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    Comet Discoverer Thomas Bopp (1949–2018) - Sky & Telescope
    http://www.skyandtelescope.com/astronomy-news/people-places-and-events/thomas-bopp-1949-2018/

    An unassuming amateur astronomer forever linked to one of the greatest comets in modern history has passed away.

    Thomas Joel Bopp, the co-discoverer of Comet Hale-Bopp, died January 5, 2018, in Phoenix, Arizona, from liver cancer. He was 68 years old.



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    Woow! Launch Of A Epsilon-3 Rocket taken by KAGAYA on January 18, 2018 @ Okinawa Island in Japan

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    https://www.utsa.edu/today/2018/01/story/Blackholes.html

    Chris Packham, associate professor of physics and astronomy at The University of Texas at San Antonio (UTSA), has collaborated on a new
    study that expands the scientific community’s understanding of black holes in our galaxy and the magnetic fields that surround them.

    Packham and astronomers lead from the University of Florida observed the magnetic field of a black hole within our own galaxy from multiple
    wavelengths for the first time. The results, which were a collective effort among several researchers, are deeply enlightening about some of
    the most mysterious objects in space.

    VIRGO
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    JunoCam/Gerald Eichstädt - jižní pól (70.2 km/pix)
    https://www.nasa.gov/image-feature/jpl/pia21975/jupiter-s-swirling-south-pole

    VIRGO
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    If you live in the western part of North America, Alaska, and the Hawaiian islands,
    you might set your alarm early the morning of Wednesday, Jan. 31 for a lunar trifecta: a pre-dawn “super blue blood moon.”

    https://www.nasa.gov/feature/super-blue-blood-moon-coming-jan-31

    VIRGO
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    Neutron-star merger yields new puzzle for astrophysicists | Newsroom - McGill University
    http://www.mcgill.ca/...m/channels/news/neutron-star-merger-yields-new-puzzle-astrophysicists-283948

    The afterglow from the distant neutron-star merger detected last August has continued to brighten – much to the surprise of astrophysicists studying
    the aftermath of the massive collision that took place about 138 million light years away and sent gravitational waves rippling through the universe.

    New observations from NASA’s orbiting Chandra X-ray Observatory, reported in Astrophysical Journal Letters, indicate that the gamma ray burst unleashed
    by the collision is more complex than scientists initially imagined.

    “Usually when we see a short gamma-ray burst, the jet emission generated gets bright for a short time as it smashes into the surrounding medium –
    then fades as the system stops injecting energy into the outflow,” says McGill University astrophysicist Daryl Haggard, whose research group led
    the new study. “This one is different; it’s definitely not a simple, plain-Jane narrow jet.”

    VIRGO
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    Asteroid 2018 BD missed Earth by just 0.10 LD on January 18
    https://watchers.news/2018/01/18/asteroid-2018-bd-missed-earth-by-just-0-10-ld-on-january-18/

    A newly discovered asteroid designated 2018 BD flew past Earth at a very close distance of 0.10 LD / 0.00026 AU (~38 895 km / 24 168 miles) at 15:43 UTC on January 18, 2018,
    some 7 hours after it was discovered. This is the fourth closest approach to our planet since 2017 EA on March 02, 2017, 2017 GM on April 4, 2017, and 2017 UJ2 on Oct 20, 2017.
    VIRGO
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    https://www.nasa.gov/...goddard/2018/nasa-team-studies-middle-aged-sun-by-tracking-motion-of-mercury

    Like the waistband of a couch potato in midlife, the orbits of planets in our solar system are expanding. It happens because the Sun’s gravitational grip gradually weakens as
    our star ages and loses mass. Now, a team of NASA and MIT scientists has indirectly measured this mass loss and other solar parameters by looking at changes in Mercury’s orbit.

    The new values improve upon earlier predictions by reducing the amount of uncertainty. That’s especially important for the rate of solar mass loss, because it’s related to
    the stability of G, the gravitational constant. Although G is considered a fixed number, whether it’s really constant is still a fundamental question in physics.

    VIRGO
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    https://www.forbes.com/...interstellar-visitor-oumuamua-was-shaped-by-cosmic-particles/#13fcfd497422

    Last year, the interstellar interloper ʻOumuamua passed through the inner Solar System. Originally thought to be a comet, then later an asteroid, this visitor turned out to have properties
    unlike any object ever seen before. It moved far too quickly and from too inclined an angle to originate from within our Solar System; neither Jupiter nor Neptune nor an Oort cloud object
    could have flung it inwards with those properties. When we examined it in detail, it appeared to have a carbon-based coating over an icy interior, yet sprouted no tail, despite reaching
    temperatures of 550 °F (290 °C). Oddest of all, it was cigar-shaped, approximately eight times as long as it was wide. While many origin theories have been proposed, an incredibly simple
    possibility may provide all the answers: simply traveling through the Milky Way for billions of years may have transformed it into the object we see today.

    VIRGO
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    Crater Neukum named after Mars Express founder / Mars Express / Space Science / Our Activities / ESA
    http://www.esa.int/...ties/Space_Science/Mars_Express/Crater_Neukum_named_after_Mars_Express_founder

    A fascinating martian crater has been chosen to honour the German physicist and planetary scientist, Gerhard Neukum, one of the founders of ESA’s Mars Express mission.

    he International Astronomical Union named the 102 km-wide crater in the Noachis Terra region “Neukum” in September last year after the camera’s leader, who died in 2014.
    Professor Neukum inspired and led the development of the high-resolution stereo camera on Mars Express, which helped to establish the regional geology and topography of Mars.

    VIRGO
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    Zooming into the galaxy cluster A1758N
    https://www.youtube.com/watch?v=wh3oqUP7w-s


    North, east, south, west: The many faces of Abell 1758 | ESA/Hubble
    http://www.spacetelescope.org/news/heic1801/

    Resembling a swarm of flickering fireflies, this beautiful galaxy cluster glows intensely in the dark cosmos, accompanied by the myriad bright lights of
    foreground stars and swirling spiral galaxies. A1758N is a sub-cluster of Abell 1758, a massive cluster containing hundreds of galaxies. Although it may
    appear serene in this NASA/ESA Hubble Space Telescope image, the sub-cluster actually comprises two even smaller structures currently in the turbulent
    process of merging.

    VIRGO
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    https://carnegiescience.edu/node/2288

    New work from a team of Carnegie cosmochemists published by Science Advances reports analyses of carbon-rich dust grains
    extracted from meteorites that show that these grains formed in the outflows from one or more type II supernovae more than
    two years after the progenitor stars exploded. This dust was then blown into space to be eventually incorporated into new
    stellar systems, including in this case, our own.

    VIRGO
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    Meteorites Brought Water To Earth During the First Two Million Years - Astrobiology Magazine
    https://www.astrobio.net/...ve/meteorites-brought-water-to-earth-during-the-first-two-million-years/

    A new study of a rare basaltic meteorites called angrites suggests that volatiles, which are elements with relatively low boiling
    points such as water, could have been brought to our planet by meteorites during the first two million years of the Solar System.

    Since elements such as water and carbon are essential ingredients to life on Earth, researchers are keen to know when they arrived
    on our planet.

    VIRGO
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    ESOcast 146 Light: Odd Behaviour of Star Reveals Black Hole in Giant Star Cluster (4K UHD)
    https://www.youtube.com/watch?v=Fa3-kD4mf0k


    Podivné chování hvězdy prozradilo černou díru skrytou v nitru hvězdokupy | ESO Česko
    http://www.eso.org/public/czechrepublic/news/eso1802/?lang

    Astronomové využívající přístroj MUSE, který pracuje ve spojení s dalekohledem ESO/VLT na observatoři Paranal v Chile, objevili v nitru hvězdokupy NGC 3201
    stálici s velmi podivným chováním. Zdá se, že obíhá kolem černé díry asi čtyřikrát hmotnější než Slunce, která by tak mohla být první neaktivní černou dírou
    nalezenou v kulové hvězdokupě a první objevenou na základě přímého pozorování gravitačního působení. Tento významný objev má zásadní dopad na naše chápání
    formování tohoto typu hvězdokup, černých děr a původu jevů doprovázených emisí gravitačních vln.

    Kulové hvězdokupy (Globular star clusters) jsou mohutnými sférickými uskupeními desetitisíců hvězd a vyskytují se ve většině galaxií. Patří k nejstarším známým
    systémům hvězd ve vesmíru a jejich vznik je datován do samotných počátků vývoje galaxií. V současnosti je v naší Galaxii známo více než 150 kulových hvězdokup.

    VIRGO
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    https://aktuelles.uni-frankfurt.de/englisch/how-massive-can-neutron-stars-be/

    The density of neutron stars is enormous, as if the entire Himalayas were compressed into a beer mug. However, there are
    indications that a neutron star with a maximum mass would collapse to a black hole if even just a single neutron were added.

    Together with his students Elias Most and Lukas Weih, Professor Luciano Rezzolla, physicist, senior fellow at the Frankfurt
    Institute for Advanced Studies (FIAS) and professor of Theoretical Astrophysics at Goethe University Frankfurt, has now solved
    the problem that had remained unanswered for 40 years: With an accuracy of a few percent, the maximum mass of non-rotating
    neutron stars cannot exceed 2.16 solar masses.

    VIRGO
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    https://www.nasa.gov/...-feature/goddard/2018/hubble-weighs-in-on-mass-of-three-million-billion-suns

    In 2014, astronomers using the NASA/ESA Hubble Space Telescope found that this enormous galaxy cluster contains the mass of a staggering three million billion suns —
    so it’s little wonder that it has earned the nickname of “El Gordo” (“the Fat One” in Spanish)! Known officially as ACT-CLJ0102-4915, it is the largest, hottest,
    and brightest X-ray galaxy cluster ever discovered in the distant Universe.

    This image was taken by Hubble’s Advanced Camera for Surveys and Wide-Field Camera 3 as part of an observing program called RELICS (Reionization Lensing Cluster
    Survey). RELICS imaged 41 massive galaxy clusters with the aim of finding the brightest distant galaxies for the forthcoming James Webb Space Telescope to study.

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