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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    Scientists reduce the chances of life on exoplanets in so-called habitable zones around red stars
    https://www.princeton.edu/...sts-reduce-chances-life-exoplanets-so-called-habitable-zones-around-red

    Is there life beyond Earth in the cosmos? Astronomers looking for signs have found that our Milky Way galaxy teems with exoplanets, some with conditions that could be right
    for extraterrestrial life. Such worlds orbit stars in so-called “habitable zones,” regions where planets could hold liquid water that is necessary for life as we know it.

    However, the question of habitability is highly complex. Researchers led by space physicist Chuanfei Dong of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics
    Laboratory (PPPL) and Princeton University have recently raised doubts about water on — and thus potential habitability of — frequently cited exoplanets that orbit red dwarfs,
    the most common stars in the Milky Way.

    In two papers in The Astrophysical Journal Letters, the scientists develop models showing that the stellar wind — the constant outpouring of charged particles that sweep out
    into space — could severely deplete the atmosphere of such planets over hundreds of millions of years, rendering them unable to host surface-based life as we know it.

    “Traditional definition and climate models of the habitable zone consider only the surface temperature,” Dong said. “But the stellar wind can significantly contribute to
    the long-term erosion and atmospheric loss of many exoplanets, so the climate models tell only part of the story.”

    To broaden the picture, the first paper looks at the timescale of atmospheric retention on Proxima Centauri b (PCb), which orbits the nearest star to our solar system,
    some four light years away. The second paper questions how long oceans could survive on “water worlds” — planets thought to have seas that could be hundreds of miles deep.
    VIRGO
    VIRGO --- ---
    +3
    Tak tohle bude (doufám) velký! Sledoval jsem přípravy už skoro 2 měsíce, zítra ve 20:05 h to vypukne na čt24:

    Hyde Park Civilizace - Evropská jižní observatoř v chilské poušti Atacama

    La Silla, Paranal a ALMA. Observatoře ESO, které provozují nejmodernější teleskopy na planetě.
    S lidmi, kteří je řídí, natáčel přímo na místě Daniel Stach. Sobotní Hyde Park Civilizace bude
    celý z téměř opačné strany Země, z míst, ze kterých je jeden z nejlepších výhledů na Jižní oblohu...
    Dívejte se v sobotu ve 20:05 na ČT24.

    Hyde Park Civilizace: Evropská jižní observatoř v chilské poušti Atacama — Česká televize
    http://www.ceskatelevize.cz/porady/10441294653-hyde-park-civilizace/217411058091202/

    https://www.facebook.com/hydeparkcivilizace/

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/press-release/goddard/2017/dance-preserves-oceans

    Heat generated by the gravitational pull of moons formed from massive collisions could extend the lifetimes of liquid water oceans beneath the surface
    of large icy worlds in our outer solar system, according to new NASA research. This greatly expands the number of locations where extraterrestrial life
    might be found, since liquid water is necessary to support known forms of life and astronomers estimate there are dozens of these worlds.
    VIRGO
    VIRGO --- ---
    1 odpověď+3
    Pěkný render. Srovnání velikostí některých kosmických roverů, sond a nosičů. Autor: Álvaro Gracia Montoya

    Space vehicles size Comparison
    https://www.youtube.com/watch?v=FiCreWWkDiI
    VIRGO
    VIRGO --- ---
    Are Spinning Black Holes Louder?
    http://aasnova.org/2017/11/29/are-spinning-black-holes-louder/

    Some distant active galaxies are louder in radio wavelengths than others. A new study explores whether
    this difference could be due to how quickly the supermassive black holes at their centers are spinning.

    VIRGO
    VIRGO --- ---
    First Finding of China's DAMPE May Shed Light on Dark Matter Research---Chinese Academy of Sciences
    http://english.cas.cn/head/201711/t20171120_186326.shtml

    The DArk Matter Particle Explorer (DAMPE, also known as Wukong) mission published its first scientific results on Nov. 30 in Nature,
    presenting the precise measurement of cosmic ray electron flux, especially a spectral break at ~0.9 TeV. The data may shed light on
    the annihilation or decay of particle dark matter.

    DAMPE is a collaboration of more than a hundred scientists, technicians and students at nine institutes in China, Switzerland and Italy,
    under the leadership of the Purple Mountain Observatory (PMO) of the Chinese Academy of Sciences (CAS). The DAMPE mission is funded by
    the strategic priority science and technology projects in space science of CAS.

    DAMPE, China’s first astronomical satellite, was launched from China’s Jiuquan Satellite Launch Center into sun-synchronous orbit on Dec.
    17th, 2015. At an altitude of about 500 km, DAMPE has been collecting data since a week after its launch.

    In its first 530 days of science operation through June 8 of this year, DAMPE has detected 1.5 million cosmic ray electrons and positrons
    above 25 GeV. The electron and positron data are characterized by unprecedentedly high energy res and low particle background contamination.

    VIRGO
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    https://www.nasa.gov/feature/goddard/2017/wasp-18b-has-smothering-stratosphere-without-water

    A NASA-led team has found evidence that the oversized planet WASP-18b is wrapped in a smothering stratosphere loaded with carbon monoxide
    and devoid of water. The findings come from a new analysis of observations made by the Hubble and Spitzer space telescopes.

    The formation of a stratosphere layer in a planet’s atmosphere is attributed to “sunscreen”-like molecules, which absorb UV and visible
    radiation coming from the star and then release that energy as heat. The new study suggests that the “hot Jupiter” WASP-18b, a massive
    planet that orbits very close to its host star, has an unusual composition, and the formation of this world might have been quite
    different from that of Jupiter as well as gas giants in other planetary systems.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/...re/jpl/pia22118/honeycomb-textured-landforms-in-northwestern-hellas-planitia

    This image from NASA's Mars Reconnaissance Orbiter (MRO) targets a portion of a group of honeycomb-textured landforms
    in northwestern Hellas Planitia, which is part of one of the largest and most ancient impact basins on Mars.

    VIRGO
    VIRGO --- ---
    Instituto de Astrofísica de Canarias - IAC - Educational Outreach
    http://www.iac.es/divulgacion.php?op1=16&id=1313&lang=en

    A study led by a researcher at the IAC and published today in Nature Astronomy points to the role of the magnetic field as responsible
    for decelerating the formation of massive stars in the center of galaxies. Without this process the Big Bang would be questioned.

    Simulación de formación estelar en la galaxia NGC1097
    https://www.youtube.com/watch?v=xLQk9--VU7c
    VIRGO
    VIRGO --- ---
    +1
    Star predicted to explode in 2022 | Space | EarthSky
    http://earthsky.org/space/star-predicted-to-explode-in-2022

    Astronomer Larry Molnar and his colleagues and students have made an unprecedented prediction of a star explosion – due in the year 2022, or thereabouts, they say –
    that’ll become visible from Earth, even to those without telescopes. The star system is an eclipsing binary system (one star passes in front of the other as seen
    from Earth) called known as KIC 9832227. New evidence suggests that these two very close stars are getting closer and will merge explosively, soon. Molnar is
    presenting his findings today (January 6, 2017) at the 229th meeting of the American Astronomical Society in Texas.

    He said the prediction, originally made in 2015, of the merging of the two stars in the KIC 9832227 system is “progressing from theory to reality” and he added:

    It’s a one-in-a-million chance that you can predict an explosion. It’s never been done before.

    VIRGO
    VIRGO --- ---
    +1
    MUSE zkoumá neprobádaná zákoutí Hubbleova ultrahlubohého pole | ESO Česko
    http://www.eso.org/public/czechrepublic/news/eso1738/

    Astronomové dokončili dosud nejhlubší spektroskopickou přehlídku

    Astronomové využívající přístroj MUSE na dalekohledu ESO/VLT v Chile provedli dosud nejhlubší spektroskopickou přehlídku vybrané části oblohy.
    Zaměřili se na oblast známou jako Hubbleovo ultrahluboké pole (Hubble Ultra Deep Field, HUDF), ve které změřili vzdálenost a zkoumali vlastnosti
    pro 1 600 velmi slabých dalekých galaxií. Nalezli také 72 dosud nepozorovaných objektů – galaxií, které nebyly zaznamenány ani na originálním
    snímku HUDF. Na základě těchto průlomových pozorování bylo vypracováno deset vědeckých prací, které budou publikovány ve speciálním vydání
    odborného časopisu Astronomy & Astrophysics. Tato studnice informací astronomům poskytuje nový pohled na průběh formování hvězd v raném vesmíru
    a umožňuje jim zkoumat pohyby i další vlastnosti mladých galaxií – vše díky mimořádnému spektroskopickému výkonu přístroje MUSE.

    Tým projektu MUSE HUDF Survey pod vedením Rolanda Bacona (Centre de recherche astrophysique de Lyon, CNRS/Université Claude Bernard Lyon 1/
    ENS de Lyon, France) využil přístroj MUSE (Multi Unit Spectroscopic Explorer) k pozorování oblasti známé jako Hubbleovo ultrahluboké pole (Ultra
    Deep Field, heic0406), což je jedno z nejdůkladněji prozkoumaných míst na jižní obloze v souhvězdí Pec (Fornax). Výsledkem provedených pozorování
    je nejhlubší spektroskopická přehlídka, jaká byla dosud provedena. Detailní informace byly získány pro celkem 1 600 vzdálených galaxií, což je
    desetkrát více objektů, než v tomto poli s obtížemi napozorovali všechny dalekohledy na povrchu Země během celé poslední dekády.

    ESOcast 140 Light: MUSE Dives into the Hubble Ultra Deep Field
    https://www.youtube.com/watch?v=5jIyoYZ2Lr4


    VIRGO
    VIRGO --- ---
    +1
    Traces of life on nearest exoplanets may be hidden in equatorial trap
    http://www.ras.org.uk/.../3074-traces-of-life-on-nearest-exoplanets-may-be-hidden-in-equatorial-trap

    New simulations show that the search for life on other planets may well be more difficult than previously assumed, in research published today in the journal
    Monthly Notices of the Royal Astronomical Society. The study indicates that unusual air flow patterns could hide atmospheric components from telescopic
    observations, with direct consequences for formulating the optimal strategy for searching for (oxygen-producing) life such as bacteria or plants on exoplanets.

    Current hopes of detecting life on planets outside of our own Solar System rest on examining the planet’s atmosphere to identify chemical compounds that may be
    produced by living beings. Ozone – a variety of oxygen – is one such molecule, and is seen as one of the possible tracers that may allow us to detect life on
    another planet from afar.

    In Earth's atmosphere, this compound forms the ozone layer that protects us from the Sun's harmful UV radiation. On an alien planet, ozone could be one piece
    in the puzzle that indicates the presence of oxygen-producing bacteria or plants.

    But now researchers, led by Ludmila Carone of the Max Planck Institute for Astronomy in Germany, have found that these tracers might be better hidden than we
    previously thought. Carone and her team considered some of the nearest exoplanets that have the potential to be Earth-like: Proxima b, which is orbiting the star
    nearest to the Sun (Proxima Centauri), and the most promising of the TRAPPIST-1 family of planets, TRAPPIST-1d.

    These are examples of planets that orbit their host star in 25 days or fewer, and as a side effect have one side permanently facing their star, and the other side
    permanently facing away. Modelling the flow of air within the atmospheres of these planets, Carone and her colleagues found that this unusual day-night divide can
    have a marked effect on the distribution of ozone across the atmosphere: at least for these planets, the major air flow may lead from the poles to the equator,
    systematically trapping the ozone in the equatorial region.

    VIRGO
    VIRGO --- ---
    +2
    News | NASA Builds its Next Mars Rover Mission
    https://www.jpl.nasa.gov/news/news.php?feature=7011

    At a glance, it looks a lot like its predecessor, the Curiosity Mars rover. But there's no doubt it's a souped-up science machine:
    It has seven new instruments, redesigned wheels and more autonomy. A drill will capture rock cores, while a caching system with a miniature
    robotic arm will seal up these samples. Then, they'll be deposited on the Martian surface for possible pickup by a future mission.

    This new hardware is being developed at NASA's Jet Propulsion Laboratory, Pasadena, California, which manages the mission for the agency.
    It includes the Mars 2020 mission's cruise stage, which will fly the rover through space, and the descent stage, a rocket-powered "sky crane"
    that will lower it to the planet's surface. Both of these stages have recently moved into JPL's Spacecraft Assembly Facility.

    NASA Begins Building Next Mars Rover Mission
    https://www.youtube.com/watch?v=s595S1Vf3PE
    JULIANNE
    JULIANNE --- ---
    VIRGO: Bohužel ne, ale snad někdy příště!
    VIRGO
    VIRGO --- ---
    Universitat de Barcelona - The study of a galactic microquasar provides the explanation for the structure of faraway radio galaxies
    http://www.ub.edu/web/ub/en/menu_eines/noticies/2017/11/048.html

    Researchers from the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and the University of Jaén have described,
    for the first time, the structure of a Z-shaped galactic microquasar. This astronomical object is considered to be a small-scale version
    of a winged radio galaxy, so far considered one of the distant sources which are potential emitters of gravitational waves. In this sense,
    the main conclusion of the study, published in Nature Communications, says that not all winged radio galaxies would be the source of
    gravitational waves, unlike what was thought so far.

    VIRGO
    VIRGO --- ---
    +1
    Astronomers create most detailed radio image of nearby dwarf galaxy - ANU
    http://www.anu.edu.au/...ll-news/astronomers-create-most-detailed-radio-image-of-nearby-dwarf-galaxy

    Astronomers at ANU have created the most detailed radio image of nearby dwarf galaxy, the Small Magellanic Cloud,
    revealing secrets of how it formed and how it is likely to evolve.

    This image was taken by CSIRO's powerful new radio telescope, the Australian Square Kilometre Array Pathfinder
    (ASKAP), and its innovative radio camera technology, known as phased array feeds.

    VIRGO
    VIRGO --- ---
    +1
    ALMA Discovers Infant Stars Surprisingly Near Galaxy’s Supermassive Black Hole - National Radio Astronomy Observatory
    https://public.nrao.edu/news/2017-alma-lmstars/

    Earliest phase of star formation ever observed in highly hostile environment

    At the center of our galaxy, in the immediate vicinity of its supermassive black hole, is a region wracked by powerful tidal forces
    and bathed in intense ultraviolet light and X-ray radiation. These harsh conditions, astronomers surmise, do not favor star formation,
    especially low-mass stars like our sun. Surprisingly, new observations from ALMA suggest otherwise.

    ALMA has revealed the telltale signs of eleven low-mass stars forming perilously close — within three light-years — to the Milky Way’s
    supermassive black hole, known to astronomers as Sagittarius A* (Sgr A*). At this distance, tidal forces driven by the supermassive
    black hole should be energetic enough to rip apart clouds of dust and gas before they can form stars.

    The presence of these newly discovered protostars (the formative stage between a dense cloud of gas and a young, shining star) suggests
    that the conditions necessary to birth low-mass stars may exist even in one of the most turbulent regions of our galaxy and possibly in
    similar locales throughout the universe.

    VIRGO
    VIRGO --- ---
    1 odpověď
    JULIANNE: Klasická nestíhačka. Bude záznam na YT?
    JULIANNE
    JULIANNE --- ---
    1 odpověď
    Tak už dnes :).

    https://www.facebook.com/events/871761692977769
    VIRGO
    VIRGO --- ---
    http://www.utu.fi/...Measure-Neutron-Star-Size-Uses-Modelling-Based-on-Thermonuclear-Explosions.aspx

    Neutron stars are made out of cold ultra-dense matter. How this matter behaves is one of the biggest mysteries in modern nuclear physics.
    Researchers developed a new method for measuring the radius of neutron stars which helps them to understand what happens to the matter
    inside the star under extreme pressure.

    [1709.09120] Neutron star mass and radius measurements from atmospheric model fits to X-ray burst cooling tail spectra
    https://arxiv.org/abs/1709.09120
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