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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    An action shot of GMTelescope Mirror Segment 4 edge generating on the Large Optical Generator (LOG) machine.
    Taken in Feb. 2017 at the University of Arizona's Richard F. Caris Mirror Laboratory. Photo Credit: Damien Jemison.

    VIRGO
    VIRGO --- ---
    Weird, hairy microbes discovered on volcano soon after eruption | New Scientist
    https://www.newscientist.com/...8570-weird-hairy-microbes-discovered-on-volcano-soon-after-eruption/

    Gone today, hair tomorrow. Soon after an underwater volcano erupted and wiped out all nearby life forms,
    hardy bacteria moved in and covered the area in a huge mat of hair-like filaments.

    These strange colonies were found by an expedition to Tagoro Volcano, near the Canary Islands, in 2014,
    two years after an eruption that reshaped 9 square kilometres of the sea floor. The researchers explored
    the area via a robotic submarine equipped with cameras and arms for collecting samples.

    VIRGO
    VIRGO --- ---
    Asteroid shock waves could have provided the building blocks for RNA - ScienceAlert
    http://www.sciencealert.com/the-building-blocks-for-rna-could-be-the-result-of-asteroid-shock-waves

    A now famous experiment conducted by chemists Stanley Miller and Harold Urey back in 1952 showed that even if we don't know for sure how the first living
    cells formed, at least some of their molecular building blocks could have been produced by simple chemical reactions under conditions on ancient Earth.

    Now, more than half a century later, researchers from France and the Czech Republic have used a similar experiment to expand this list of potential
    ingredients to include all four RNA bases, filling in some possible stepping stones on the pathway from chemical soup to the origins of life.

    While the results don't show how life probably formed, they do demonstrate that conditions on Earth roughly 3.5 to 4 billion years ago could have been
    sufficient to produce the toolbox of compounds necessary for biochemistry.

    Those conditions include what was probably an atmosphere without oxygen – referred to as a reducing atmosphere – and warm bodies of water containing
    nitrogen and carbon-based molecules such as ammonia and methane.

    Miller and Urey dissolved these two compounds in a sterile flask of water with some hydrogen gas for their experiment, letting it sit for a week before
    shocking the solution with electricity to simulate lightning strikes.
    VIRGO
    VIRGO --- ---
    NASA VR: Cassini's Grand Finale (360 view)
    https://www.youtube.com/watch?v=hFjzFSidX3s
    VIRGO
    VIRGO --- ---
    Cassini: Mission to Saturn: Cassini Completes Final - and Fateful - Titan Flyby
    https://saturn.jpl.nasa.gov/news/3030/cassini-completes-final-and-fateful-titan-flyby/

    NASA's Cassini spacecraft has had its last close brush with Saturn's hazy moon Titan and is now beginning its final set of 22 orbits around the ringed planet.

    The spacecraft made its 127th and final close approach to Titan on April 21 at 11:08 p.m. PDT (2:08 a.m. EDT on April 22), passing at an altitude of about 608
    miles (979 kilometers) above the moon's surface.

    Cassini transmitted its images and other data to Earth following the encounter. Scientists with Cassini's radar investigation will be looking this week at their
    final set of new radar images of the hydrocarbon seas and lakes that spread across Titan's north polar region. The planned imaging coverage includes a region
    previously seen by Cassini's imaging cameras, but not by radar. The radar team also plans to use the new data to probe the depths and compositions of some of
    Titan's small lakes for the first (and last) time, and look for further evidence of the evolving feature researchers have dubbed the "magic island."

    VIRGO
    VIRGO --- ---
    Petr Horálek - Lovy skvostů temné oblohy (Pátečníci 10.6.2016)
    https://www.youtube.com/watch?v=2Kv-H1spCLU
    VIRGO
    VIRGO --- ---
    NASA’s Cassini, Voyager Missions Suggest New Picture of Sun’s Interaction with Galaxy
    https://www.nasa.gov/...assini-voyager-missions-suggest-new-picture-of-sun-s-interaction-with-galaxy

    New data from NASA’s Cassini mission, combined with measurements from the two Voyager spacecraft and NASA’s Interstellar Boundary Explorer, or IBEX,
    suggests that our sun and planets are surrounded by a giant, rounded system of magnetic field from the sun — calling into question the alternate view
    of the solar magnetic fields trailing behind the sun in the shape of a long comet tail.

    The sun releases a constant outflow of magnetic solar material — called the solar wind — that fills the inner solar system, reaching far past the orbit
    of Neptune. This solar wind creates a bubble, some 23 billion miles across, called the heliosphere. Our entire solar system, including the heliosphere,
    moves through interstellar space. The prevalent picture of the heliosphere was one of comet-shaped structure, with a rounded head and an extended tail.
    But new data covering an entire 11-year solar activity cycle show that may not be the case: the heliosphere may be rounded on both ends, making its
    shape almost spherical. A paper on these results was published in Nature Astronomy on April 24, 2017.

    VIRGO
    VIRGO --- ---
    Jellyfish-shaped galaxy found in Abell 2670 cluster
    https://phys.org/news/2017-04-jellyfish-shaped-galaxy-abell-cluster.html

    Using the Multi Unit Spectroscopic Explorer (MUSE), astronomers have identified a new elliptical jellyfish-like galaxy in the Abell 2670 cluster.
    The newly detected galaxy showcases spectacular one-sided tails of gas and young stars, which indicates intense ram-pressure stripping.
    The findings were presented Apr. 18 in a paper published on the arXiv pre-print server.

    VIRGO
    VIRGO --- ---
    Messier 78: HD View of A Reflective Nebula : VLT Telescope / Astronomy Video
    https://www.youtube.com/watch?v=cXtyRnUdBFM
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/jpl/pia20527/dark-chasm

    The low angle of the sun over Tethys' massive canyon, Ithaca Chasma (near the terminator, at right), highlights the contours of this enormous rift.

    Ithaca Chasma is up to 60 miles (100 kilometers) wide, and runs nearly three-fourths of the way around icy Tethys (660 miles or 1,062 kilometers across).
    The canyon has a maximum depth of nearly 2.4 miles (4 kilometers) deep.

    VIRGO
    VIRGO --- ---
    A Black Hole in a Low Mass X-Ray Binarysu201715 | www.cfa.harvard.edu/
    https://www.cfa.harvard.edu/news/su201715

    A globular cluster is a roughly spherical ensemble of stars (as many as several million) that are gravitationally bound together,
    and typically located in the outer regions of galaxies. Low mass X-ray binary stars (LMXBs) are systems in which one star is compact
    (a neutron star or black hole) and is accreting matter from a companion star. Astronomers have long noticed that there are fractionally
    many more LMXBs in globular clusters than elsewhere in the galaxy, an overabundance that is usually attributed to the high stellar
    density in globular clusters. But this calls attention to another unusual feature of the LMXBs in globulars. In the galactic field,
    most LXMBs are formed from binary stars as they age and evolve, but in globular clusters it has been shown that most LMXBs form when
    compact objects encounter and then capture another star. There are many neutron stars in clusters, but black holes that form in these
    dense stellar environments are expected either to sink down to the center of the cluster or else to be gravitationally ejected from
    the cluster after they are formed. Indeed, all of the LMXBs seen in globular clusters are of the type with a neutron star.

    VIRGO
    VIRGO --- ---
    NASA's Fermi Catches Gamma-ray Flashes from Tropical Storms
    https://www.nasa.gov/...ture/goddard/2017/nasas-fermi-catches-gamma-ray-flashes-from-tropical-storms

    About a thousand times a day, thunderstorms fire off fleeting bursts of some of the highest-energy light naturally found on Earth.
    These events, called terrestrial gamma-ray flashes (TGFs), last less than a millisecond and produce gamma rays with tens of millions
    of times the energy of visible light. Since its launch in 2008, NASA's Fermi Gamma-ray Space Telescope has recorded more than 4,000 TGFs,
    which scientists are studying to better understand how the phenomenon relates to lightning activity, storm strength and the life cycle of
    storms.

    Now, for the first time, a team of NASA scientists has analyzed dozens of TGFs launched by the largest and strongest weather systems on
    the planet: tropical storms, hurricanes and typhoons. A paper describing the research was published March 16 in the Journal of Geophysical
    Research: Atmospheres.

    NASA's Fermi Catches Gamma-ray Flashes from Tropical Storms
    https://www.youtube.com/watch?v=f3lx0yzZXNQ
    DARKMOOR
    DARKMOOR --- ---
    Pokračování seriálu o vodě ve Sluneční soustavě.
    Radioaktivita a gravitace. Proč i zmrzlé planety mají kapalnou vodu - iDNES.cz
    http://technet.idnes.cz/zmrzle-planety-maji-kapalnou-vodu-d5p-/veda.aspx?c=A170421_134752_veda_mla
    VIRGO
    VIRGO --- ---
    VIRGO
    VIRGO --- ---
    Ancient carvings show comet hit Earth and triggered mini ice age | New Scientist
    https://www.newscientist.com/...12-ancient-carvings-show-comet-hit-earth-and-triggered-mini-ice-age/

    Ancient symbols carved into stone at an archaeological site in Turkey tell the story
    of a devastating comet impact that triggered a mini ice age more than 13,000 years ago.

    Evidence from the carvings, made on a pillar known as the Vulture Stone, suggests that
    a swarm of comet fragments hit the Earth in around 11000 BC.

    VIRGO
    VIRGO --- ---
    Simulated galaxies provide fresh evidence of dark matter - Durham University
    https://www.dur.ac.uk/news/newsitem/?itemno=31169

    Further evidence of the existence of dark matter – the mysterious substance that is believed to hold the Universe together –
    has been produced by Cosmologists at Durham University.

    Using sophisticated computer modelling techniques, the research team simulated the formation of galaxies in the presence of
    dark matter and were able to demonstrate that their size and rotation speed were linked to their brightness in a similar way
    to observations made by astronomers.

    One of the simulations is pictured, showing the main ingredients that make up a galaxy: the stars (blue), the gas from which
    the stars are born (red), and the dark matter halo that surrounds the galaxy (light grey).

    VIRGO
    VIRGO --- ---
    Jeden z prvních snímků z úplně posledního průletu kolem Titanu. Fňuk...

    VIRGO
    VIRGO --- ---
    Quickest we could visit another star is 69 years – here’s how | New Scientist
    https://www.newscientist.com/.../2128443-quickest-we-could-visit-another-star-is-69-years-heres-how/

    René Heller at the Max Planck Institute for Solar System Research in Göttingen, Germany, says we could reach and orbit Sirius,
    the brightest star in our night sky, in just 69 years. This is despite the fact that it is twice as far away as our nearest stars
    in the Alpha Centauri system, which would take at least 90 years to reach.

    A private enterprise called Breakthrough Starshot is hoping to send a fleet of small, wafer-thin spacecraft to visit Alpha Centauri
    and explore its tantalising planets. Previous estimates by Breakthrough Starshot have indicated they could reach Alpha Centauri in
    just 20 years, travelling at a fifth of the speed of light. But this estimate was calculated for a flyby mission, passing by
    in just a few seconds.
    VIRGO
    VIRGO --- ---
    W. M. KECK OBSERVATORY ACHIEVES FIRST LIGHT WITH NEW INSTRUMENT
    INTEGRAL FIELD SPECTROGRAPH TO PROVIDE UNPRECEDENTED VIEW OF DEEP SPACE
    W. M. Keck Observatory Achieves First Light with KCWI W. M. Keck Observatory
    http://www.keckobservatory.org/recent/entry/kcwi_achieves_first_light

    W. M. Keck Observatory recently captured the very first successful science data from its newest, cutting-edge instrument, the Keck Cosmic Web Imager (KCWI).

    KCWI captures three-dimensional data, as opposed to the traditional two-dimensional image or spectrum of conventional instruments. In a single observation,
    it records an image of the object at multiple wavelengths allowing scientists to explore both the spatial dimension (as in an image) and the spectral
    dimension (or color) of an object.

    Maunakea Astronomy
    http://campaign.r20.constantcontact.com/...r?m=1101336625199&ca=06c51e0c-6f5e-4028-8b97-f0bc391e923d

    VIRGO
    VIRGO --- ---
    News | New Look at 2004's Martian Hole-in-One Site
    https://www.jpl.nasa.gov/news/news.php?feature=6824

    A new observation from NASA's Mars Reconnaissance Orbiter (MRO) captures the landing platform that the rover Opportunity left behind in Eagle Crater
    more than 13 years and 27 miles (or 44 kilometers) ago. A series of bounces and tumbles after initial touchdown plunked the airbag-cushioned lander
    into the crater, a mere 72 feet (22 meters) across, on Jan. 25, 2004, Universal Time (Jan. 24, PST). The scene includes Eagle Crater and Opportunity's
    nearby parachute and backshell, from the April 10, 2017, observation by MRO's High Resolution Imaging Science Experiment (HiRISE) camera.

    This is the first color view from HiRISE of the Eagle Crater scene. Mars Reconnaissance Orbiter began orbiting Mars more than two years after
    Opportunity's landing. One of the first images from HiRISE in 2006 showed Opportunity at the rim of a much larger crater, Victoria, nearly 4 miles
    (about 6 kilometers) south of the landing site. The camera also recorded a monochrome view of Eagle Crater that year.

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