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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Very bright fireball spotted over Gilgit-Baltistan region, in Northern Pakistan on March 15, 2017

    “Meteor” crossing over parts of Gilgit-Baltistan spreads fear and panic
    https://www.youtube.com/watch?v=LukuQwTV0TA
    VIRGO
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    There’s a supernova occurring right now in NGC 5643 | Astronomy.com
    http://astronomy.com/news/2017/03/supernova-ngc-5643
    Meet “Bob,” the second Type Ia supernova in the galaxy since 2013

    Announced by Rachael Beaton at the the Observatories of the Carnegie Institution for Science in Pasadena, CA, and known as 2017cbv
    (though Beaton has nicknamed it Bob), the explosion was spotted in NGC 5643, a spiral galaxy in the constellation Lupus. The area of
    the sky it inhabits is also part of the area covered by the Carnegie-Irvine Galaxy Survey, a project aimed at gathering optical and near-
    infrared images of bright Southern Hemisphere galaxies. NGC 5643 was also the home galaxy of SN 2013aa, which occurred in early 2013.

    VIRGO
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    VIRGO
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    Experiments Show Titan Lakes May Fizz with Nitrogen
    https://www.nasa.gov/feature/jpl/experiments-show-titan-lakes-may-fizz-with-nitrogen

    A recent NASA-funded study has shown how the hydrocarbon lakes and seas of Saturn's moon Titan might occasionally erupt with dramatic patches of bubbles.

    For the study, researchers at NASA's Jet Propulsion Laboratory in Pasadena, California, simulated the frigid surface conditions on Titan, finding that
    significant amounts of nitrogen can be dissolved in the extremely cold liquid methane that rains from the skies and collects in rivers, lakes and seas.
    They demonstrated that slight changes in temperature, air pressure or composition can cause the nitrogen to rapidly separate out of solution, like the
    fizz that results when opening a bottle of carbonated soda.

    NASA's Cassini spacecraft has found that the composition of Titan's lakes and seas varies from place to place, with some reservoirs being richer in ethane
    than methane. "Our experiments showed that when methane-rich liquids mix with ethane-rich ones -- for example from a heavy rain, or when runoff from
    a methane river mixes into an ethane-rich lake -- the nitrogen is less able to stay in solution," said Michael Malaska of JPL, who led the study.

    The result is bubbles. Lots of bubbles.

    VIRGO
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    Fossil or inorganic structure? Scientists dig into early life forms
    https://phys.org/news/2017-03-fossil-inorganic-scientists-early-life.html

    An international team of researchers discovered that inorganic chemicals can self-organize into complex structures that mimic primitive life on Earth.

    Florida State University Professor of Chemistry Oliver Steinbock and Professor Juan Manuel Garcia-Ruiz of the Consejo Superior de Investigaciones Cientificas
    (Spanish National Research Council) in Granada, Spain published an article in Wednesday's edition of Science Advances that shows fossil-like objects grew in
    natural spring water abundant in the early stages of the planet. But they were inorganic materials that resulted from simple chemical reactions.

    This complicates the identification of Earth's earliest microfossils and redefines the search for life on other planets and moons.

    "Inorganic microstructures can potentially be indistinguishable from ancient traces of life both in morphology and chemical composition," Garcia-Ruiz said.

    Scientists had seen hints of this in past lab work, but now through Steinbock and Garcia-Ruiz's research, it is clear that this also happened in nature.

    VIRGO
    VIRGO --- ---
    VIRGO:
    Dark Matter Less Influential in Galaxies in Early Universe | ESO United Kingdom
    http://www.eso.org/public/unitedkingdom/news/eso1709/?lang

    VIRGO
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    Comparison of rotating disc galaxies in the distant Universe and the present day | ESO United Kingdom
    https://www.eso.org/public/unitedkingdom/videos/eso1709c/

    Comparison of rotating disc galaxies in the distant Universe and the present day. The imaginary galaxy on the left is in the nearby Universe
    and the stars in its outer parts are orbiting rapidly due to the presence of large amounts of dark matter around the central regions. On the
    other hand the galaxy at the right, which is in the distant Universe, and seen as it was about ten billion years ago, is rotating more slowly
    in its outer parts as dark matter is more diffuse.

    The size of the difference is exaggerated in this schematic view to make the effect clearer. The distribution of dark matter is shown in red.

    Comparison of rotating disc galaxies in the distant Universe and the present day
    https://www.youtube.com/watch?v=gjBcCYl27iM
    VIRGO
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    VIRGO
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    Protostar Blazes Bright, Reshaping Its Stellar Nursery - NRAO: Revealing the Hidden Universe
    https://public.nrao.edu/news/pressreleases/2017-alma-protostar-outburst

    A massive protostar, deeply nestled in its dust-filled stellar nursery, recently roared to life, shining nearly 100 times brighter than before. This outburst, apparently triggered by
    an avalanche of star-forming gas crashing onto the surface of the star, supports the theory that young stars can undergo intense growth spurts that reshape their surroundings.

    Astronomers made this discovery by comparing new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile with earlier observations from the Submillimeter
    Array (SMA) in Hawaii.

    "We were amazingly fortunate to detect this spectacular transformation of a young, massive star,” said Todd Hunter, an astronomer at the National Radio Astronomy Observatory (NRAO)
    in Charlottesville, Va., and lead author on a paper published in the Astrophysical Journal Letters. "By studying a dense star-forming cloud with both ALMA and the SMA, we could see
    that something dramatic had taken place, completely changing a stellar nursery over a surprisingly short period of time."

    VIRGO
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    Quantum Entanglement Documentary Atomic Physics and Reality
    https://www.youtube.com/watch?v=SEjte11wPeI
    VIRGO
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    Early Earth Had a Hazy, Methane-filled Atmosphere | College of Computer, Mathematical, and Natural Sciences
    http://cmns.umd.edu/news-events/features/3826
    Thick clouds of methane forced hydrogen to leave the atmosphere, enabling today’s oxygen-rich air to develop

    More than 2.4 billion years ago, Earth’s atmosphere was inhospitable, filled with toxic gases that drove wildly fluctuating surface
    temperatures. Understanding how today’s world of mild climates and breathable air took shape is a fundamental question in Earth science.

    New research from the University of Maryland, the University of St. Andrews, NASA’s Jet Propulsion Laboratory, the University of Leeds
    and the Blue Marble Space Institute of Science suggests that long ago, Earth’s atmosphere spent about a million years filled with a methane-
    rich haze. This haze drove a large amount of hydrogen out of the atmosphere, clearing the way for massive amounts of oxygen to fill the air.
    This transformation resulted in an atmosphere much like the one that sustains life on Earth today.
    VIRGO
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    VIRGO
    VIRGO --- ---
    Looking for signs of the first stars
    https://phys.org/news/2017-03-stars.html

    It may soon be possible to detect the universe's first stars by looking for the blue colour they emit on explosion.

    he universe was dark and filled with hydrogen and helium for 100 million years following the Big Bang. Then, the first stars appeared,
    and metals were created by thermonuclear fusion reactions within stars.

    These metals were spread around the galaxies by exploding stars or 'supernovae'. Studying first-generation supernovae, which are more
    than 13 billion years old, provides a glimpse into what the universe might have looked like when the first stars, galaxies and super-
    massive black holes formed. But to-date, it has been difficult to distinguish a first-generation supernova from a later one.

    New research, led by Alexey Tolstov from the Kavli Institute for the Physics and Mathematics of the Universe, has identified characteristic
    differences between these supernovae types after experimenting with supernovae models based on observations of extremely metal-poor stars.

    VIRGO
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    https://www.nasa.gov/image-feature/goddard/2017/nasas-webb-telescope-ghostly-lights-out-inspection

    What happens when the lights are turned out in the enormous clean room that currently houses NASA's James Webb Space Telescope? The technicians who are inspecting
    the telescope and its expansive golden mirrors look like ghostly wraiths in this image as they conduct a "lights out inspection" in the Spacecraft Systems Development
    and Integration Facility (SSDIF) at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

    The clean room lights were turned off to inspect the telescope after it experienced vibration and acoustic testing. The contamination control engineer used a bright
    flashlight and special ultraviolet flashlights to inspect for contamination because it's easier to find in the dark.

    NASA photographer Chris Gunn said "The people have a ghostly appearance because it's a long exposure." He left the camera's shutter open for a longer than normal time
    so the movement of the technicians appear as a blur. He also used a special light "painting" technique to light up the primary mirror.

    VIRGO
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    Scientists identify a black hole choking on stardust | MIT News
    http://news.mit.edu/2017/black-hole-choking-stardust-0315
    Data suggest black holes swallow stellar debris in bursts.

    In the center of a distant galaxy, almost 300 million light years from Earth, scientists have discovered a supermassive black hole
    that is “choking” on a sudden influx of stellar debris.

    In a paper published today in Astrophysical Journal Letters, researchers from MIT, NASA’s Goddard Space Flight Center, and elsewhere
    report on a “tidal disruption flare” — a dramatic burst of electromagnetic activity that occurs when a black hole obliterates a nearby
    star. The flare was first discovered on Nov. 11, 2014, and scientists have since trained a variety of telescopes on the event to learn
    more about how black holes grow and evolve.

    The MIT-led team looked through data collected by two different telescopes and identified a curious pattern in the energy emitted by
    the flare: As the obliterated star’s dust fell into the black hole, the researchers observed small fluctuations in the optical and UV bands
    of the electromagnetic spectrum. This very same pattern repeated itself 32 days later, this time in the X-ray band.

    VIRGO
    VIRGO --- ---
    Astronomers discover 16 new high-redshift quasars
    https://phys.org/news/2017-03-astronomers-high-redshift-quasars.html

    Using a new color selection technique, astronomers have detected 16 new luminous, high-redshift quasars. The discovery could be very important for
    understanding of the early universe, as such high-redshift, quasi-stellar objects provide essential clues on the evolution of the intergalactic medium,
    quasar evolution and early super-massive black hole growth. The findings were presented in a paper published Mar. 10 on the arXiv pre-print repository.

    JULIANNE
    JULIANNE --- ---
    Astrobiologie: Přístroje pro sondy JUICE a ExoMars 2020 - Kalendář akcí | Přírodovědci.cz
    https://www.prirodovedci.cz/kalendar-akci/astrobiologie-pristroje-pro-sondy-juice-a-exomars-2020
    JULIANNE
    JULIANNE --- ---
    Prof. Aharon Oren přednese na naší fakultě dvě přednášky — Přírodovědecká fakulta UK
    https://www.natur.cuni.cz/...ulta/aktuality/prof-aharon-ohren-prednese-na-nasi-fakulte-dve-prednasky
    VIRGO
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    https://www.nasa.gov/image-feature/jpl/pia17213/farewell-to-mimas
    In its season of "lasts," NASA's Cassini spacecraft made its final close approach to Saturn's moon Mimas on January 30, 2017. At closest approach,
    Cassini passed 25,620 miles (41,230 kilometers) from Mimas. All future observations of Mimas will be from more than twice this distance.

    This mosaic is one of the highest resolution views ever captured of the icy moon. Close approaches to Mimas have been somewhat rare during Cassini's
    mission, with only seven flybys at distances of less than 50 000 kilometers.

    VIRGO
    VIRGO --- ---
    Starquakes reveal surprises about birth of stars in our galaxy | UNSW Newsroom
    http://newsroom.unsw.edu.au/...science-tech/starquakes-reveal-surprises-about-birth-stars-our-galaxy

    A study of the internal sound waves created by starquakes, which make stars ring like a bell, has provided
    unprecedented insights into conditions in the turbulent gas clouds where stars were born 8 billion years ago.

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