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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Close encounters of the stellar kind / Gaia / Space Science / Our Activities / ESA
    http://www.esa.int/Our_Activities/Space_Science/Gaia/Close_encounters_of_the_stellar_kind

    The movements of more than 300 000 stars surveyed by ESA’s Gaia satellite reveal that rare close encounters with our Sun
    might disturb the cloud of comets at the far reaches of our Solar System, sending some towards Earth in the distant future.

    As the Solar System moves through the Galaxy, and as other stars move on their own paths, close encounters are inevitable –
    though ‘close’ still means many trillions of kilometres.

    A star, depending on its mass and speed, would need to get within about 60 trillion kilometres before it starts to have an
    effect on the Solar System’s distant reservoir of comets, the Oort Cloud, which is thought to extend out to 15 trillion
    kilometres from the Sun, 100 000 times the Sun–Earth distance.

    For comparison, the outermost planet Neptune orbits at an average distance of about 4.5 billion kilometres, or 30 Sun–Earth
    distances. The gravitational influence of stars that pass near the Oort Cloud could perturb the paths of comets residing there,
    jolting them onto orbits that bring them in to the inner Solar System.

    While this is thought to be responsible for some of the comets that appear in our skies every hundred to thousand years,
    it also has the potential to put comets on a collision course with Earth or other planets.

    Tracking stellar motions
    https://www.youtube.com/watch?v=KCEr8PqeLWI
    VIRGO
    VIRGO --- ---
    Hubble delivers first hints of possible water content of TRAPPIST-1 planets | ESA/Hubble
    http://www.spacetelescope.org/news/heic1713/

    An international team of astronomers used the NASA/ESA Hubble Space Telescope to estimate whether there might be water
    on the seven earth-sized planets orbiting the nearby dwarf star TRAPPIST-1. The results suggest that the outer planets
    of the system might still harbour substantial amounts of water. This includes the three planets within the habitable
    zone of the star, lending further weight to the possibility that they may indeed be habitable.

    Animation of the planets orbiting TRAPPIST-1
    https://www.youtube.com/watch?v=KPWnBhjXSd0
    VIRGO
    VIRGO --- ---
    Discovery of a Metal-Poor Little Cub
    http://aasnova.org/2017/08/30/discovery-of-a-metal-poor-little-cub/

    The discovery of an extremely metal-poor star-forming galaxy in our local universe, dubbed Little Cub,
    is providing astronomers with front-row seats to the quenching of a near-pristine galaxy.

    VIRGO
    VIRGO --- ---
    Ultraviolet light may be ultra important in search for life
    https://phys.org/news/2017-08-ultraviolet-ultra-important-life.html

    A new study by Sukrit Ranjan of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., and colleagues suggests
    that red dwarf stars might not emit enough UV light to kick-start the biological processes most familiar to our planet. For example,
    certain levels of UV might be necessary for the formation of ribonucleic acid, a molecule necessary for all forms of known life.

    VIRGO
    VIRGO --- ---
    NASA's Juno spacecraft will make its seventh science flyby over Jupiter's mysterious cloud tops on Friday, Sept. 1,
    at 2:49 p.m. PDT (5:49 p.m. EDT and 21:49 UTC). At the time of perijove (defined as the point in Juno's orbit when it is
    closest to the planet's center), the spacecraft will be about 2,200 miles (3,500 kilometers) above the planet's cloud tops.

    Juno Scientists Prepare for Seventh Science Pass of Jupiter | Mission Juno
    https://www.missionjuno.swri.edu/news/scientists-prepare-for-seventh-jupiter-pass
    VIRGO
    VIRGO --- ---
    Researchers Recover an Ancient Nova
    https://www.amnh.org/explore/news-blogs/research-posts/researchers-recover-an-ancient-nova

    On a cold March night in Seoul almost 600 years ago, Royal Imperial Astrologers spotted a bright new star in the tail of the constellation Scorpius.
    It was seen for just 14 days before fading from view. From these ancient records, modern astronomers determined that what the ancient astronomers
    saw in 1437 was a nova explosion, but they had been unable to find the binary star system that caused it—until now.

    A new study published today by the journal Nature pinpoints the location of the old nova, which now undergoes smaller-scale “dwarf nova” eruptions.
    The work supports that idea that novae go through a very long-term life cycle after erupting, fading to obscurity for thousands of years, then building
    back up to become full-fledged novae once more.

    “This is the first nova that’s ever been recovered with certainty based on the Chinese, Korean, and Japanese records of almost 2,500 years,”
    said the study’s lead author Michael Shara, a curator in the Museum’s Department of Astrophysics.

    http://www.nature.com/nature/journal/v548/n7669/full/nature23644.html

    VIRGO
    VIRGO --- ---
    Uff...Silný kafe takhle navečír. Pokud nejde o ojedinělý jev, pak by se v Galaxii mohlo vyskytovat
    až kolem 1B terestrických planet podobných Zemi. Sladké sny! Ať žije Drakeova rovnice :))

    System: YZ Ceti
    Discovered by: European Southern Observatory
    Found on: August 14, 2017
    Key Facts: Three Earth-mass worlds found around a small red star only 12 light-years away.

    NASA's perspective: YZ Ceti is the nearest multi-planet system found orbiting a red dwarf star or "M dwarf."
    While the three planets are outside their star's habitable zone, they are all about the same mass as Earth.
    YZ Ceti b, c, and d are the lowest mass planets found with the planet-hunting method radial velocity. NASA's
    TESS and James Webb telescopes will study more exoplanets around nearby stars in 2018, in hopes of finding
    another Earth.

    https://exoplanets.nasa.gov/news/1451/discovery-alert-three-earth-mass-neighbors/

    https://arxiv.org/pdf/1708.03336.pdf

    VIRGO
    VIRGO --- ---
    House-sized near Earth objects rarer than we thought
    https://phys.org/news/2017-08-house-sized-earth-rarer-thought.html

    A survey for NEOs being carried out with DECam on the 4-m Blanco telescope at the Cerro Tololo Inter-American Observatory has now estimated the number of objects
    in near-Earth orbit that are similar in size to the Chelyabinsk impactor. Lori Allen, Director of the Kitt Peak National Observatory and the lead investigator on
    the study, explained, "There are around 3.5 million NEOs larger than 10 meters, a population ten times smaller than inferred in previous studies. About 90% of
    these NEOs are in the Chelyabinsk size range of 10-20 meters."

    The study, to be published in the Astronomical Journal, is the first to derive, from a single observational data set with no external model assumptions, the size
    distribution of NEOs from 1 kilometer down to 10 meters. A similar result was obtained in an independent study that analyzed multiple data sets (Tricarico 2017).

    House-Sized Near Earth Objects Rarer Than We Thought
    https://www.youtube.com/watch?v=XgQghDjaZwE
    VIRGO
    VIRGO --- ---
    Distant galaxy sends out 15 high-energy radio bursts | Berkeley News
    http://news.berkeley.edu/2017/08/30/distant-galaxy-sends-out-15-high-energy-radio-bursts/

    reakthrough Listen, an initiative to find signs of intelligent life in the universe, has detected 15 brief but
    powerful radio pulses emanating from a mysterious and repeating source – FRB 121102 – far across the universe.

    Fast radio bursts are brief, bright pulses of radio emission from distant but largely unknown sources, and FRB
    121102 is the only one known to repeat: more than 150 high-energy bursts have been observed coming from the object,
    which was identified last year as a dwarf galaxy about 3 billion light years from Earth.

    VIRGO
    VIRGO --- ---
    Repríza JPL telkonu "Grande Finale"
    NASA Live: JPL - Previewing Cassini's Grand Finale
    https://www.youtube.com/watch?v=Y5MqidJ_HfA
    VIRGO
    VIRGO --- ---
    Researchers hypothesize how the universe became filled with light | Iowa Now
    https://now.uiowa.edu/2017/08/researchers-hypothesize-how-universe-became-filled-light

    Black holes may have punctured darkened galaxies, allowed light to escape

    Soon after the Big Bang, the universe went completely dark.

    The intense, seminal event that created the cosmos churned up so much hot, thick gas that light was completely trapped.
    Much later—perhaps as many as one billion years after the Big Bang—the universe expanded; became more transparent;
    and eventually filled up with galaxies, planets, stars, and other objects that give off visible light. That’s the universe
    we know today.

    How it emerged from the cosmic dark ages to a clearer, light-filled state remains a mystery.

    In a new study, researchers at the University of Iowa offer a theory of how that happened. They think black holes that dwell
    in the center of galaxies fling out matter so violently that the ejected material pierces its cloudy surroundings, allowing light
    to escape. The researchers arrived at their theory after observing a nearby galaxy from which ultraviolet light is escaping.

    VIRGO
    VIRGO --- ---
    ALMA nalezla mohutné skryté zásoby plynu ve vzdálené galaxii | ESO Česko
    http://www.eso.org/public/czechrepublic/news/eso1727/?lang

    První pozorování molekul CH+ ve vzdálené galaxii s aktivní hvězdotvorbou poskytují nový pohled na historii vzniku hvězd ve vesmíru

    Zooming in on the Cosmic Eyelash
    https://www.youtube.com/watch?v=4KytNHz30AY


    Astronomové využili radioteleskop ALMA k pozorování turbulentních rezervoárů chladného plynu obklopujících vzdálené galaxie, ve kterých probíhá
    prudký vývoj nových hvězd. Díky tomu, že se vědcům poprvé v historii podařilo v těchto galaxiích detekovat molekulu CH+, otevírá tento výzkum
    zcela nové okno umožňující zkoumat kritické fáze vývoje hvězd ve vesmíru. Přítomnost těchto molekul přináší nový pohled na způsob, jakým galaxie
    dosáhnou prodloužení období bouřlivé hvězdotvorby. Výsledky byly publikovány v prestižním vědeckém časopise Nature.

    VIRGO
    VIRGO --- ---
    TOXYGEN: Včerejší 10h srážení iontů olova na LHC (detektor ALICE provádí srážky
    většinou poslední týden v měsíci), a úhrnná vzdálenost, kterou částice urazily.
    TOXYGEN
    TOXYGEN --- ---
    VIRGO: co to je?
    VIRGO
    VIRGO --- ---
    Zajímavý vývoj kardinální otázky...
    Cassini hints at young age for Saturn's rings - BBC News
    http://www.bbc.com/news/science-environment-41091333

    The spectacular rings of Saturn may be relatively young, perhaps just 100 million years or so old.
    This is the early interpretation of data gathered by the Cassini spacecraft on its final orbits of the giant world.
    If confirmed, it means we are looking at Saturn at a very special time in the age of the Solar System.
    Cassini is scheduled to make only two more close-in passes before driving itself to destruction in Saturn's atmosphere on 15 September.

    VIRGO
    VIRGO --- ---
    What Spacecraft Saw During the 2017 Solar Eclipse
    https://www.youtube.com/watch?v=7RmczjiDlwE
    VIRGO
    VIRGO --- ---
    The end-Cretaceous mass extinction was rather unpleasant | Ars Technica
    https://arstechnica.com/science/2017/08/the-end-cretaceous-mass-extinction-was-rather-unpleasant/

    Climate simulation shows how long soot blotted out the Sun.

    There are a few hellish episodes in Earth’s unfathomably long history that make even Hollywood’s most bombastic disaster movie
    look like a sunny picnic. The end-Cretaceous extinction is the most well-known, since it wiped out the dinosaurs (minus the birds,
    of course) and opened the door for the mammalian revolution—which most human beings regard as generally a good thing.

    Though the story is probably familiar, there are still significant questions about exactly what happened during that cataclysm.
    Many species were seemingly in trouble before that colossal meteoroid crashed into the coastal Yucatan, perhaps partly because of
    a long-lived series of massive volcanic eruptions in what is now India. This has led some to question whether the impact was as
    deadly as it's made out to be. But we've also filled in some details of just how the meteoroid impact would mess up the Earth,
    and these include mind-blowing tsunamis, rampant wildfires, and see-sawing climate effects. So how lethal was the impact?

    VIRGO
    VIRGO --- ---
    VIRGO: NASA’s Johnson Space Center Closes Through Labor Day for Tropical Storm Harvey
    https://www.nasa.gov/...sa-s-johnson-space-center-closes-through-labor-day-for-tropical-storm-harvey

    VIRGO
    VIRGO --- ---
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