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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    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.

    VIRGO
    VIRGO --- ---
    New phenomenon discovered in the night sky
    https://watchers.news/2017/04/21/new-phenomenon-discovered-in-the-night-sky/

    A new phenomenon seen as a giant purple streak of light in the night sky has been recently discovered and, for lack of a better word,
    named Steve. Steve was discovered thanks to scientists, citizen scientists, ground-based imagers and ESA's magnetic field Swarm mission.

    VIRGO
    VIRGO --- ---
    Intriguing "lake" of dust hanging out at the bottom of a multi-layered crater
    HiRISE | Slope Monitoring (ESP_049317_1675)
    http://www.uahirise.org/ESP_049317_1675

    VIRGO
    VIRGO --- ---
    Death by Asteroid: The Most Likely Ways for a Space Rock to Kill You
    http://www.space.com/36532-killer-asteroids-most-likely-death-causes.html

    If you live in fear of an asteroid strike, here's some detail to help flesh out your nightmares.

    A killer space rock is most likely to get you via violent winds that fling you against something hard or powerful shock waves that rupture your
    internal organs, according to a new study.

    "This is the first study that looks at all seven impact effects generated by hazardous asteroids and estimates which are, in terms of human loss,
    most severe," lead author Clemens Rumpf, a senior research assistant at the University of Southampton in the United Kingdom, said in a statement.

    Rumpf and his colleagues simulated 50 000 asteroid strikes around the globe using computer models. These artificial impacts involved space rocks
    15 to 400 meters — the size range that hits Earth most frequently, the scientists said.

    Then, the team estimated the percentage of deaths caused by each of the seven effects Rumpf referred to: shock waves, wind blasts, heat, flying
    debris, cratering, seismic shaking and tsunamis.

    Wind and shock waves were the most deadly, together accounting for more than 60 percent of all lives lost. (Though these two effects act in concert,
    wind blasts were far more devastating than shock waves, the study found.) The sizzling heat of an impact was responsible for nearly 30 percent of
    deaths, and tsunamis took most of the rest.

    Asteroid impact effects and their immediate hazards for human populations - Rumpf - 2017 - Geophysical Research Letters - Wiley Online Library
    http://onlinelibrary.wiley.com/doi/10.1002/2017GL073191/full

    Increase in average casualties per impactor size and the increasing contribution by each impact effect. First casualties due to wind blast and thermal radiation occurred at 18 m.
    Impactors of 40 m produced the first pressure losses, and first surface impacts were recorded for impactors larger than 56 m. (b) Impact effect dominance distribution over
    the asteroid size range up to 400 m.

    VIRGO
    VIRGO --- ---
    A creative way to scan for life on other Earths: Build a 60-mirror, 74-meter telescope called Colossus.
    Colossus Telescope
    http://the-colossus.com/technology.html

    VIRGO
    VIRGO --- ---
    BBC - Future - Infographic: Absolute zero to ‘absolute hot’
    http://www.bbc.com/future/story/20131218-absolute-zero-to-absolute-hot
    BBC Future takes the temperature of our planet – and the Universe – to find the hottest and coldest things ever measured.

    VIRGO
    VIRGO --- ---
    Approximate true color close-up of Saturn's rings seen by Cassini on April 19th with processing of Kevin Gill.
    Assembled from raw uncalibrated red, green, and ultraviolet (UV3) filtered images. Credits: NASA/JPL-Caltech/SSI/Kevin M. Gill
    Saturn - April 19 2017 | Assembled from raw uncalibrated red… | Flickr
    https://www.flickr.com/photos/kevinmgill/34049287211/

    VIRGO
    VIRGO --- ---
    The future of planetary defense
    By Amy Mainzer

    The future of planetary defense - Mainzer - 2017 - Journal of Geophysical Research: Planets - Wiley Online Library
    http://onlinelibrary.wiley.com/doi/10.1002/2017JE005318/full

    VIRGO
    VIRGO --- ---
    Tune in to 2 days of discussions on "newly discovered Earth-like 'exoplanets' in the Alpha
    Centauri and TRAPPIST-1 planetary systems" and what these discoveries mean for the search for life.

    Breakthrough Initiatives to Webcast Search for Life Conference on Newfound Exoplanets
    Breakthrough Initiatives
    https://breakthroughinitiatives.org/Events/DiscussConference

    You can watch it via FB: https://www.facebook.com/BreakthroughPrize

    The event will take place April 20 and 21, and will feature presentations and panel discussions that focus on two recent discoveries of
    potentially habitable planets orbiting stars relatively close to Earth's solar system, according to a statement from the organization.

    The entire conference will be webcast to the public via Facebook Live. The complete a list of speakers and the conference schedule can be
    found on the Breakthrough Initiatives website. The program begins at 9 a.m. PDT (12 p.m. EDT/1600GMT) each day, and runs until 5:50 p.m.
    PDT on April 20 and until 4:30 p.m. PDT on April 21.
    VIRGO
    VIRGO --- ---
    VIRGO:
    First detection of equatorial dark dust lane in a protostellar disk at submillimeter wavelength
    https://vimeo.com/213738858
    VIRGO
    VIRGO --- ---
    First clear image made of accretion disk surrounding young star
    https://phys.org/news/2017-04-image-accretion-disk-young-star.html

    A team of researchers from the U.S. and Taiwan has captured the first clear image of a young star surrounded by an accretion disk.
    In their paper published in the journal Science Advances, the team describes how the image was captured and details of their find.

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