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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Discovery about rare nitrogen molecules offers clues to makeup of other life-supporting planets | UCLA
    http://newsroom.ucla.edu/...trogen-molecules-offers-clues-to-makeup-of-other-life-supporting-planets

    team of scientists using a state-of-the-art UCLA instrument reports the discovery of a planetary-scale “tug-of-war” of life,
    deep Earth and the upper atmosphere that is expressed in atmospheric nitrogen.

    The Earth’s atmosphere differs from the atmospheres of most other rocky planets and moons in our solar system in that it is rich
    in nitrogen gas, or N2; the Earth’s atmosphere is 78 percent nitrogen gas. Titan, the largest of Saturn’s more than 60 moons, is
    the other body in our solar system with a nitrogen-rich atmosphere that resembles ours.

    Compared with other key elements of life — such as oxygen, hydrogen and carbon — molecular nitrogen is very stable. Two nitrogen
    atoms combine to form N2 molecules that stay in the atmosphere for millions of years.

    The majority of nitrogen has an atomic mass of 14. Less than one percent of nitrogen has an extra neutron. While this heavy isotope,
    nitrogen-15, is rare, N2 molecules that contain two nitrogen-15s — which chemists call 15N15N — are the rarest of all N2 molecules.

    The team of scientists measured the amount of 15N15N in air and discovered that this rare form of nitrogen gas is far more abundant
    than scientists had expected. The Earth’s atmosphere contains about two percent more 15N15N than can be accounted for by geochemical
    processes occurring near the Earth’s surface.

    “This excess was not known before because nobody could measure it,” said senior author Edward Young, a UCLA professor of geochemistry
    and cosmochemistry. “Our one-of-a-kind Panorama mass spectrometer allows us to see this for the first time. We conducted experiments
    showing that the only way for this excess of 15N15N to occur is by rare reactions in the upper atmosphere. Two percent is a huge excess.”

    Young said the enrichment of 15N15N in Earth’s atmosphere is a signature that’s unique to our planet. “But it also gives us a clue about
    what signatures of other planets might look like, especially if they are capable of supporting life as we know it.”
    VIRGO
    VIRGO --- ---
    Scientists observe supermassive black hole in infant universe | MIT News
    http://news.mit.edu/2017/scientists-observe-supermassive-black-hole-infant-universe-1206

    A team of astronomers, including two from MIT, has detected the most distant supermassive black hole ever observed.
    The black hole sits in the center of an ultrabright quasar, the light of which was emitted just 690 million years
    after the Big Bang. That light has taken about 13 billion years to reach us — a span of time that is nearly equal
    to the age of the universe.

    The black hole is measured to be about 800 million times as massive as our sun — a Goliath by modern-day standards
    and a relative anomaly in the early universe.

    VIRGO
    VIRGO --- ---
    Massive Primordial Galaxies Found Swimming in Vast Ocean of Dark Matter - National Radio Astronomy Observatory
    https://public.nrao.edu/news/2017-alma-galaxies-dark-matter/

    Astronomers expect that the first galaxies, those that formed just a few hundred million years after the Big Bang, would share many similarities with some of the dwarf
    galaxies we see in the nearby universe today. These early agglomerations of a few billion stars would then become the building blocks of the larger galaxies that came
    to dominate the universe after the first few billion years.

    Ongoing observations with the Atacama Large Millimeter/submillimeter Array (ALMA), however, have discovered surprising examples of massive, star-filled galaxies
    seen when the cosmos was less than a billion years old. This suggests that smaller galactic building blocks were able to assemble into large galaxies quite quickly.

    The latest ALMA observations push back this epoch of massive-galaxy formation even further by identifying two giant galaxies seen when the universe was only 780 million
    years old, or about 5 percent its current age. ALMA also revealed that these uncommonly large galaxies are nestled inside an even-more-massive cosmic structure, a halo
    of dark matter several trillion times more massive than the sun.

    The two galaxies are in such close proximity — less than the distance from the Earth to the center of our galaxy — that they will shortly merge to form the largest galaxy
    ever observed at that period in cosmic history. This discovery provides new details about the emergence of large galaxies and the role that dark matter plays in assembling
    the most massive structures in the universe.

    The researchers report their findings in the journal Nature.

    VIRGO
    VIRGO --- ---
    Clay minerals on Mars may have formed in primordial steam bath | News from Brown
    http://news.brown.edu/articles/2017/12/marsclay

    New research suggests that the bulk of clay minerals on Mars could have been formed as the planet’s crust
    cooled and solidified, not by later interactions with water on the surface as has long been assumed.

    VIRGO
    VIRGO --- ---
    Why is Earth Magnetized and Venus Not? - Sky & Telescope
    http://www.skyandtelescope.com/astronomy-news/why-is-earth-magnetized-and-venus-not-magnetized/

    A new analysis reveals that the gigantic impact that led to the Moon's formation might have also switched on Earth's magnetic field.

    VIRGO
    VIRGO --- ---
    První světlo pro ESPRESSO – lovce exoplanet nové generace | ESO Česko
    http://www.eso.org/public/czechrepublic/news/eso1739/?lang

    Spektrograf ESPRESSO úspěšně provedl svá první pozorování. Nový přístroj instalovaný na dalekohledu ESO/VLT v Chile bude díky dosud nedosažitelné
    přesnosti měření změn ve spektrech hvězd pátrat po jejich extrasolárních planetách. Zařízení bude navíc schopné získávat záření ze všech čtyř
    hlavních dalekohledů systému VLT najednou a tímto způsobem sesbírá tolik světla, jako jeden teleskop se zrcadlem o průměru 16 m.

    Přístrojem ESPRESSO (SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations), který byl nedávno instalován na dalekohled ESO/VLT
    na observatoři Paranal v severním Chile [1], prošlo první světlo. Tento nový echelletový spektrograf třetí generace je nástupcem úspěšného zařízení
    HARPS, které je stále v provozu na observatoři ESO/La Silla. Zatímco spektrograf HARPS je při měření rychlosti pomocí Dopplerova jevu schopen
    dosáhnout přesnosti kolem 1 m/s, ESPRESSO by mělo – díky technologickému vývoji a využití na dalekohledu s mnohem větším zrcadlem –
    provádět stejná měření s přesností v řádu několika centimetrů za sekundu.

    ESOcast 141 Light: ESPRESSO — the Next Generation Planet Hunter
    https://www.youtube.com/watch?v=99lcMp2dv_4


    ESPRESSO achieves First Light
    https://www.youtube.com/watch?v=AaDzvQFgdec


    VIRGO
    VIRGO --- ---
    What If the Big Bang Wasn't the Beginning? New Study Proposes Alternative
    https://www.space.com/38982-no-big-bang-bouncing-cosmology-theory.html

    ..."The Big Bang as the initial singularity is only a speculation," Silva Neves told Space.com.
    He said that "there are many observations in cosmology" that support the hypothesis that the
    universe went through a period of rapid expansion, but that there is no direct evidence that
    this expansion started with a singularity.

    In a paper published Aug. 29 in the journal General Relativity and Gravitation, Silva Neves,
    a researcher at the Mathematics, Statistics & Scientific Computation Institute (IMECC-UNICAMP)
    of the University of Campinas, in Brazil, proposes an alternative cosmological model that does
    away with the necessity of this original singularity. His model includes a concept known as
    bouncing cosmology.

    VIRGO
    VIRGO --- ---
    https://www.swri.org/press-release/collisions-after-moon-formation-remodeled-early-earth

    Southwest Research Institute scientists recently modeled the protracted period of bombardment following the Moon’s formation, when leftover planetesimals
    pounded the Earth. Based on these simulations, scientists theorize that moon-sized objects delivered more mass to the Earth than previously thought.

    Early in its evolution, Earth sustained an impact with another large object, and the Moon formed from the resulting debris ejected into an Earth-orbiting
    disk. A long period of bombardment followed, the so-called “late accretion,” when large bodies impacted the Earth delivering materials that were accreted
    or integrated into the young planet.

    “We modeled the massive collisions and how metals and silicates were integrated into Earth during this ‘late accretion stage,’ which lasted for hundreds
    of millions of years after the Moon formed,” said SwRI’s Dr. Simone Marchi, lead author of a Nature Geoscience paper outlining these results. “Based on
    our simulations, the late accretion mass delivered to Earth may be significantly greater than previously thought, with important consequences for
    the earliest evolution of our planet.”

    Previously, scientists estimated that materials from planetesimals integrated during the final stage of terrestrial planet formation made up about half
    a percent of the Earth’s present mass. This is based on the concentration of highly “siderophile” elements — metals such as gold, platinum and iridium,
    which have an affinity for iron — in the Earth’s mantle. The relative abundance of these elements in the mantle points to late accretion, after Earth’s
    core had formed. But the estimate assumes that all highly siderophile elements delivered by the later impacts were retained in the mantle.

    BLACKHEAD
    BLACKHEAD --- ---
    VIRGO: Measured in the time domain? Or how?
    VIRGO
    VIRGO --- ---
    Strejda Albert o5 bez ztráty kytičky
    In a first, Galileo’s gravity experiment is re-created in space | Science News
    https://www.sciencenews.org/article/first-galileo-gravity-experiment-re-created-space-einstein

    Galileo’s most famous experiment has taken a trip to outer space. The result? Einstein was right yet again.
    The experiment confirms a tenet of Einstein’s theory of gravity with greater precision than ever before.

    According to science lore, Galileo dropped two balls from the Leaning Tower of Pisa to show that they fell at the same rate no matter their composition.
    Although it seems unlikely that Galileo actually carried out this experiment, scientists have performed a similar, but much more sensitive experiment in
    a satellite orbiting Earth. Two hollow cylinders within the satellite fell at the same rate over 120 orbits, or about eight days’ worth of free-fall time,
    researchers with the MICROSCOPE experiment report Dec 4 in Physical Review Letters. The cylinders’ accelerations match within two-trillionths of a percent.

    VIRGO
    VIRGO --- ---
    Snellen - Exoplanets and the search for extraterrestrial life
    https://www.youtube.com/watch?time_continue=2&v=ZNkhILRp354
    VIRGO
    VIRGO --- ---
    VLT’s SPHERE spies rocky worlds | ESO United Kingdom
    http://www.eso.org/public/unitedkingdom/images/potw1749a/

    These images were taken by ESO’s SPHERE (Spectro-Polarimetric High-contrast Exoplanet REsearch) instrument, installed on ESO’s Very Large Telescope
    (VLT) at the Paranal Observatory, Chile. These strikingly-detailed views reveal four of the millions of rocky bodies in the main asteroid belt,
    a ring of asteroids between Mars and Jupiter that separates the rocky inner planets of the Solar System from the gaseous and icy outer planets.

    VIRGO
    VIRGO --- ---
    Astronomer’s map reveals location of mysterious fast-moving gas | University News : The University of Western Australia
    http://www.news.uwa.edu.au/...rnational/astronomer-s-map-reveals-location-mysterious-fast-moving-gas

    An Australian scientist has created the most detailed map ever of clouds of high-velocity gas in the Universe around us.

    The map covers the entire sky and shows curious clouds of neutral hydrogen gas that are moving at a different speed to
    the normal rotation of the Milky Way.

    It was created by astronomer Dr Tobias Westmeier, from The University of Western Australia node of the International Centre
    for Radio Astronomy Research, and published today in the leading journal Monthly Notices of the Royal Astronomical Society.

    Dr Westmeier said the map suggests that at least 13 per cent of the sky is covered by high-velocity clouds.

    VIRGO
    VIRGO --- ---
    Metal asteroid Psyche is all set for an early visit from NASA
    https://theconversation.com/metal-asteroid-psyche-is-all-set-for-an-early-visit-from-nasa-88044

    Three times further away from the sun than the Earth lies an enormous lump of metal. Around 252km in diameter,
    the metallic “M-class” asteroid 16 Psyche is the target of NASA’s next mission to the belt of giant rocks that
    encircles the inner solar system. And the space agency now plans to visit it much sooner than originally planned.

    Not only has the launch has been brought forward one year to the summer of 2022, but NASA’s scientists have also
    found a way to get to Psyche (pronounced SYKe-ee) much faster by taking a more efficient trajectory. The new route
    means the Psyche spacecraft won’t have to swing around the Earth to build up speed and won’t pass as close to the
    sun, so it needs less heat protection. It is now due to arrive in 2026, four years earlier than the original timeline.

    BROUKOID
    BROUKOID --- ---
    VIRGO: obavam se ze to je ale spatne - minimalne ten lunochod je moc malej. Ve skutecnosti ma prumer "talire" cca 2m.
    VIRGO
    VIRGO --- ---
    Recipe for a comet | Max Planck Society
    https://www.mpg.de/11813538/chemical-elements-rosetta-comet-67p?c=2249

    Rearchers analyse which chemical elements make up comet 67P/Churyumov-Gerasimenko

    The dust that comet 67P/Churyumov-Gerasimenko emits into space consists to about one half of organic molecules.
    The dust also belongs to the most pristine and carbon-rich material known in our solar system; it has hardly
    changed since its birth. These are the results of the COSIMA team, an instrument onboard the Rosetta spacecraft,
    which investigated the comet. In their current study, the involved researchers including scientists from the Max
    Planck Institute for Solar System Research analyze as comprehensively as never before, what chemical elements
    constitute cometary dust.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/jpl/pia21972/jupiter-blues

    The Juno spacecraft captured this image when the spacecraft was only 11,747 miles (18,906 kilometers) from the tops of Jupiter’s clouds —
    that’s roughly as far as the distance between New York City and Perth, Australia. The color-enhanced image, which captures a cloud system
    in Jupiter’s northern hemisphere, was taken on Oct. 24, 2017 at 10:24 a.m. PDT (1:24 p.m. EDT) when Juno was at a latitude of 57.57 degrees
    (nearly three-fifths of the way from Jupiter’s equator to its north pole) and performing its ninth close flyby of the gas giant planet.

    The spatial scale in this image is 7.75 miles/pixel (12.5 kilometers/pixel).

    Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager.

    VIRGO
    VIRGO --- ---
    The Mysterious Star MWC349su201744 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201744

    Molecular clouds in interstellar space can sometimes produce natural masers (the radio wavelength analogs of lasers) that shine with
    bright, narrow beams of radiation. Regions of active star formation generate some of the most spectacular such masers -- in one case
    radiating as much energy in a single spectral line as does our Sun in its entire visible spectrum. In these sources, the maser
    radiation comes from molecules like water or OH that are excited by collisions and the radiation environment around the young stars.

    VIRGO
    VIRGO --- ---
    Giant Black Hole Pair Photobombs Andromeda Galaxy | NASA
    https://www.nasa.gov/...on_pages/chandra/news/giant-black-hole-pair-photobombs-andromeda-galaxy.html

    It seems like even black holes can’t resist the temptation to insert themselves unannounced into photographs. A cosmic photobomb found as a background
    object in images of the nearby Andromeda galaxy has revealed what could be the most tightly coupled pair of supermassive black holes ever seen.

    Astronomers made this remarkable discovery using X-ray data from NASA’s Chandra X-ray Observatory and optical data from ground-based telescopes, Gemini-
    North in Hawaii and the Caltech’s Palomar Transient Factory in California.

    This unusual source, called LGGS J004527.30+413254.3 (J0045+41 for short), was seen in optical and X-ray images of Andromeda, also known as M31. Until
    recently, scientists thought J0045+41 was an object within M31, a large spiral galaxy located relatively nearby at a distance of about 2.5 million light
    years from Earth. The new data, however, revealed that J0045+41 was actually at a much greater distance, around 2.6 billion light years from Earth.

    “We were looking for a special type of star in M31 and thought we had found one,” said Trevor Dorn-Wallenstein of the University of Washington in Seattle,
    WA, who led the paper describing this discovery. “We were surprised and excited to find something far stranger!”

    Even more intriguing than the large distance of J0045+41 is that it likely contains a pair of giant black holes in close orbit around each other.
    The estimated total mass for these two supermassive black holes is about two hundred million times the mass of our Sun.

    Previously, a different team of astronomers had seen periodic variations in the optical light from J0045+41, and, believing it to be a member of M31,
    classified it as a pair of stars that orbited around each other about once every 80 days.

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