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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    SLAPPY
    SLAPPY --- ---
    Probíhající, budoucí a plánované mise k planetkám:

    Malé planety neboli planetky, někdy nazývané také asteroidy, tvoří zdaleka nejpočetnější skupinu těles ve Sluneční soustavě. Od malých kamínků až po stakilometrové balvany jsou rozesety skoro po všech oblastech našeho systému. Jejich různé velikosti, odlišná složení i okolní podmínky vytváří téměř nekonečnou rozmanitost světů. Není proto divu, že se k různým typům těchto těles chystá hned několik průzkumných sond.


    Mise k blízkozemním psteroidům

    Kuiperův pás
    DARKMOOR
    DARKMOOR --- ---
    JULIANNE: Tak to jsem nečekal, zvlášť když planeta musí být celkem blízko...
    Já narazil akorát na jeden starší článek, kde je řešená síla hvězdného větru a co to dělá s oběžnou drahou různě velikých objektů (ale přiznávám, že na mě už to je poněkud složité, nemám dostatečné vědomosti :))
    https://luth.obspm.fr/~luthier/mottez/articles/2012_sf2a_PSR_planet.pdf

    VIRGO: To je pech :(
    VIRGO
    VIRGO --- ---
    Alan Stern‏ - "BIG DAY! We're kicking off the @NewHorizons2015 meetings to select flyby distance & other aim point parameters for 2014MU69 on 1 Jan 2019!"

    A quick prototype model showing New Horizons encountering the two-lobed 2014 MU69 from Kevin M. Gill.

    VIRGO
    VIRGO --- ---
    Giant ringed planet likely cause of mysterious eclipses
    http://www2.warwick.ac.uk/newsandevents/pressreleases/giant_ringed_planet

    A giant gas planet – up to 50x the mass of Jupiter, encircled by a ring of dust – is likely hurtling around a star
    over 1000 light years away from Earth, according to international team of astronomers, led by University of Warwick

    Light from young star - PDS 110 in the Orion constellation - is regularly blocked by large object, thought to be an orbiting planet

    Next eclipse predicted to take place in September this year, and amateur astronomers across the world will be able to witness it

    Moons may be forming in the habitable zone around the star – leading to possibility that life could thrive within system

    VIRGO
    VIRGO --- ---
    Physics - Viewpoint: Neutron-Star Implosions as Heavy-Element Sources
    https://physics.aps.org/articles/v10/89

    A dramatic scenario in which a compact black hole eats a spinning neutron star from inside might explain a nearby galaxy’s unexpectedly high abundance of heavy elements.

    The lightest of the chemical elements—hydrogen, helium, and lithium—were created in the hot, early phase of the Universe, about a minute after the big bang. Heavier elements
    were forged later—in the nuclear fires of many generations of stars and during supernova explosions. But the origin of many rare chemical species, particularly the heaviest
    elements, remains uncertain. In particular, recent observations of a nearby galaxy enriched with heavy elements challenge traditional nucleosynthesis models. George Fuller
    of the University of California, San Diego, and colleagues now propose a novel scenario for the origin of the heaviest elements, including gold, platinum, and uranium. Their
    hypothesis involves tiny black holes inducing neutron-star implosions and, if viable, would in one fell swoop offer solutions to other astrophysical riddles beyond heavy element
    synthesis.

    VIRGO
    VIRGO --- ---
    Čištění a výměna reflexní vrstvy prim. zrcadla VLT.
    Ani jsem nedýchal, když jsem na to koukal. Největší respekt!

    ESOcast 120: Chile Chill 10 – “VLT Main Mirror Recoating” | ESO Česko
    http://www.eso.org/public/czechrepublic/videos/esocast120a/

    ESOcast 120: Chile Chill 10 – “VLT Main Mirror Recoating”
    https://www.youtube.com/watch?v=vKAaFOuVvKs
    VIRGO
    VIRGO --- ---
    JULIANNE: Kdybych nebyl v práci, tak se u toho snad rozbrečím.
    Už víc než rok plánuji výpravu na start, v práci jsem zařídil termín, a teď vše padlo.
    Ta zpráva o kolizním start. okně se objevila už před několika měsíci, ale to ještě
    vypadalo optimisticky na volbu jiného nosiče. Dnes už nahlas mluví o několikaměsíčním
    zpoždění. Katastrofa. Delay se může natáhnout klidně i na půl roku.

    Jediná limitace start. okna JWST je zvýšená sluneční aktivita, jinak můžou letět kdykoliv.
    A je mi jasné, že chtějí mít ne 100 ale 1000% jistotu, že vše klapne. Ach jo... :-(((
    JULIANNE
    JULIANNE --- ---
    VIRGO: To snad ne :(!
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/jpl/pia21340/prometheus-and-the-ghostly-f-ring

    The thin sliver of Saturn's moon Prometheus lurks near ghostly structures in Saturn's narrow F ring in this view from NASA's Cassini spacecraft.
    Many of the narrow ring's faint and wispy features result from its gravitational interactions with Prometheus (86 kilometers, or 53 miles across).

    The view was acquired at a distance of approximately 680,000 miles (1.1 million kilometers) from Saturn. Image scale is 4 miles (6 kilometers) per pixel.

    VIRGO
    VIRGO --- ---
    Magnetic Fields in Massive, Star Formation Coressu201729 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201729

    Studies of molecular clouds have revealed that star formation usually occurs in a two step process. First, supersonic flows compress the clouds into dense
    filaments light-years long, after which gravity collapses the densest material in the filament into cores. In this scenario, massive cores (each more than
    about twenty solar–masses) preferentially form at intersections where filaments cross, producing sites of clustered star formation. The process sounds
    reasonable and is expected to be efficient, but the observed rate of star formation in dense gas is only a few percent of the rate expected if the material
    really were freely collapsing. To solve the problem, astronomers have proposed that magnetic fields support the cores against the collapse induced by self-gravity.

    VIRGO
    VIRGO --- ---
    Tak tohle je peklo. :((

    http://www.spaceflightinsider.com/...ssions/space-observatories/james-webb-space-telescope-delayed/

    The much delayed and over budget next-generation +James Webb Space Telescope (JWST) (JWST) has suffered another setback prior to its journey
    to the launch pad: the October 2018 launch may be in conflict with Europe’s BepiColombo mission to Mercury. Both spacecraft are to be flown
    on Ariane 5 boosters, but the spaceport at Kourou, French Guiana, cannot support two flights in the same month. BepiColombo has priority due
    to the tight launch window to reach Mercury. This will result in the JWST having its launch date pushed back to 2019 at the earliest.

    ---

    https://www.nasa.gov/.../2017/sunshield-layers-fully-integrated-on-nasa-s-james-webb-space-telescope

    The five sunshield layers responsible for protecting the optics and instruments of NASA’s James Webb Space Telescope are now fully installed.

    Northrop Grumman Corporation in Redondo Beach, California who designed the Webb telescope’s optics and spacecraft bus for NASA’s Goddard Space
    Flight Center in Greenbelt, Maryland, integrated the final flight layers into the sunshield subsystem. The team is now folding and stowing the
    layers, in preparation for deployment tests in August.

    The sunshield layers work together to reduce the temperatures between the hot and cold sides of the observatory by approximately 570 degrees
    Fahrenheit. Each successive layer of the sunshield, made of kapton, is cooler than the one below. All layers were installed and tested in June
    and July 2017 at Northrop Grumman Corporation’s Space Park facility in Redondo Beach.

    “This is a huge milestone for the Webb telescope as we prepare for launch,” said Jim Flynn, Webb sunshield manager, Northrop Grumman Aerospace
    Systems. “The groundbreaking tennis court sized sunshield will shield the optics from heat and assist in providing the imaging of the formation
    of stars and galaxies more than 13.5 billion years ago.”

    VIRGO
    VIRGO --- ---
    Home > OSHI - Online Showcase of Herschel Images
    http://oshi.esa.int/#detail=image.html?id=82

    An image from +European Space Agency, ESA's Herschel space observatory of the iconic Eagle Nebula. This is a three-colour composite with colours
    assigned as blue=70um, green=160um, red=250um. Herschel’s far infrared instruments were able for the first time to peer through the vast swathes
    of optically opaque material at this level of detail, showcasing the thermal emissions from the vast clouds and dust, which make up the nebula.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/...ard/2017/nasa-s-transiting-exoplanet-survey-satellite-passes-critical-review

    NASA’s Transiting Exoplanet Survey Satellite (TESS) has moved one step closer to launch after successfully passing its Systems
    Integration Review (SIR), an independent review from independent technical and scientific experts who have deemed the mission
    ready to begin installation of its scientific instrument onto the spacecraft.

    Scheduled for launch in March 2018, TESS will be NASA’s next planet-hunting mission, searching for planets orbiting stars outside
    our solar system, known as exoplanets. TESS will use four wide-field cameras to scan nearly the entire sky, monitoring the nearest
    and brightest stars for temporary dips in the light they emit that may indicate a planet passing in front — an event known as a transit.

    TESS Camera Mounting Timelapse
    https://www.youtube.com/watch?v=SOj1PCtG2yk
    VIRGO
    VIRGO --- ---
    An artificial eclipse for imaging extrasolar planets | Stanford News
    http://news.stanford.edu/2017/08/07/artificial-eclipse-imaging-extrasolar-planets/

    As anyone anticipating this month’s eclipse knows, one way to dim a star is to block it with something else – a moon,
    perhaps. Or in the case of distant stars whose light masks orbiting exoplanets, a shade-throwing satellite might do.

    JULIANNE
    JULIANNE --- ---
    JULIANNE: Tak zpět; jak jsem se v novém článku (Patruno & Kama 2017) dočetla dál, je to tam, i když jen jako maličká sekce (dva krátké odstavce a tabulka na str. 9). Zdá se, že proti ztrátě atmosféry by stačilo magnetické pole srovnatelné se zemským, což mě překvapuje.
    JULIANNE
    JULIANNE --- ---
    DARKMOOR: Vyloženě k planetám pulsarů jsem na to nenarazila, ale existuje dost modelů k planetám silně aktivních hvězd hlavní posloupnosti, které by se snad daly upravit pro příslušný účel. To bohužel neumím.
    DARKMOOR
    DARKMOOR --- ---
    JULIANNE: JULIANNE: Zkoušel někdo spočítat jak silné by muselo být planetární magnetické pole, aby ochránilo atmosféru planety u neutronové hvězdy?
    VIRGO
    VIRGO --- ---
    http://aasnova.org/2017/08/04/collisions-around-a-black-hole-mean-mealtime/

    When a normally dormant supermassive black hole burps out a brief flare, it’s assumed that a star was torn apart and
    fell into the black hole. But a new study suggests that some of these flares might have a slightly different cause.

    JULIANNE
    JULIANNE --- ---
    DARKMOOR: Ale mně to nevadí, jen mě to překvapilo :). Tomuhle tématu jsem se stejně alespoň protentokrát neměla v úmyslu do hloubky věnovat. A oni alespoň v prvním oddílu článku pracují s daty místo pouze teoretických předpovědí, co je ještě zachytitelné. Já jsem se momentálně zasekla na efektivní teplotě PSR B1257+12. Dostatečně jasnou hodnotu jsem zatím nedohledala, v různých pracích se liší i řádově a obecně teploty neutronových hvězd se liší přes několik řádů. Už se nedivím, že autoři nejnovější práce považují planety v systému za pravděpodobně zmrzlé, zatímco třeba Miller a Hamilton by je odpařili...
    DARKMOOR
    DARKMOOR --- ---
    JULIANNE: Je to jasné, vycucli ti tu myšlenku z hlavy. Pro příště neváhat, psát a publikovat ;)
    Kliknutím sem můžete změnit nastavení reklam