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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
    VIRGO
    VIRGO --- ---
    +1
    https://www.nasa.gov/feature/jpl/dawn-finds-possible-ancient-ocean-remnants-at-ceres

    Minerals containing water are widespread on Ceres, suggesting the dwarf planet may have had a global ocean in the past.
    What became of that ocean? Could Ceres still have liquid today? Two new studies from NASA's Dawn mission shed light on these questions.

    VIRGO
    VIRGO --- ---
    Space in Images - 2017 - 10 - Cloudy with a chance of protons
    http://www.esa.int/spaceinimages/Images/2017/10/Cloudy_with_a_chance_of_protons

    In September, Gaia unexpectedly detected a large quantity of protons – subatomic particles – emitted by a solar flare.

    In this image, captured by Gaia’s Wave Front Sensor – a sort of ‘camera within a camera’ in its main star-sensing instrument –
    the streaks of ‘snow’ are trails of individual protons. During normal space weather conditions, the image would only include
    one or two proton trails. The long trail running horizontally across the image indicates a particularly energetic proton.

    This proton storm was also reported by NASA’s GOES weather satellite, which is equipped with a particle-sensing instrument.

    VIRGO
    VIRGO --- ---
    +2
    ESA Science & Technology: Rosetta finds comet plume powered from deep below
    http://sci.esa.int/rosetta/59702-rosetta-finds-comet-plume-powered-from-deep-below/

    The plume was seen by ESA's Rosetta spacecraft on 3 July 2016, just a few months before the end of the mission
    and as Comet 67P/Churyumov–Gerasimenko was heading away from the Sun at a distance of almost 500 million km.

    VIRGO
    VIRGO --- ---
    +2
    Astronomers Spot First-Known Interstellar "Comet" - Sky & Telescope
    http://www.skyandtelescope.com/astronomy-news/astronomers-spot-first-known-interstellar-comet/

    Telescopes only picked it up a week ago, but it's likely been traveling through interstellar space for millions of years.



    VIRGO
    VIRGO --- ---
    Comet Mission Reveals "Missing Link" in our Understanding of Planet Formation
    http://www.ras.org.uk/...comet-mission-reveals-missing-link-in-our-understanding-of-planet-formation

    The missing link in our understanding of planet formation has been revealed by the first ever spacecraft to orbit and land on a comet,
    say German scientists. The study is published in a recent edition of the journal Monthly Notices of the Royal Astronomical Society.

    Professor Blum explains the implications of the team's observations "Our results show that only a single model for the formation of
    larger solid bodies in the young solar system may be considered for Chury. According to this formation model, 'dust pebbles' are
    concentrated so strongly by an instability in the solar nebula that their joint gravitational force ultimately leads to a collapse."

    This process forms the missing link between the well-established formation of 'dust pebbles' ('planetary building blocks' formed in
    the solar nebula by sticking collisions between dust and ice particles) and the gravitational accretion of planetesimals into planets,
    which scientists have pondered over for years.

    JULIANNE
    JULIANNE --- ---
    +2
    VIRGO: Na podobnou notu:
    Clarkesworld Magazine - Science Fiction & Fantasy : An Optimist and Pessimist Tackle the Fermi Paradox by Julie Novakova and Tomas Petrasek
    http://clarkesworldmagazine.com/novakova-petrasek_10_17/
    VIRGO
    VIRGO --- ---
    1 odpověď
    Is there anybody out there? | The Planetary Society
    http://www.planetary.org/blogs/jason-davis/2017/20171025-seti-anybody-out-there.html
    VIRGO
    VIRGO --- ---
    +2
    Myslím, že je jí možná až moc. :) 5 prací na arXivu za jediný den...

    Speed of spacetime ripples rules out some alternatives to dark energy

    What detecting gravitational waves means for the expansion of the universe | Science News
    https://www.sciencenews.org/article/what-detecting-gravitational-waves-means-expansion-universe

    ...The cosmological constant idea matches observations of the wider universe, but it has some theoretical difficulties. Dark energy is about
    120 orders of magnitude weaker than theorists calculate it should be (SN Online: 11/18/13), a mismatch that makes scientists uncomfortable.

    Also, different methods for measuring the rate of expansion come up with slightly different numbers (SN: 8/6/16, p. 10). Measurements based on exploding stars
    suggest that distant galaxies are speeding away from each other at 73 kilometers per second for each megaparsec (about 3.3 million light-years) of space between
    them. But observations based on the cosmic microwave background, ancient light that encodes information about the conditions of the early universe, found that
    the expansion rate is 67 km/s per MP. The disagreement suggests that either one of the measurements is wrong, or the theory behind dark energy needs a tweak.

    XCHAOS
    XCHAOS --- ---
    -2
    https://www.nature.com/nature/journal/v493/n7430/pdf/nature11717.pdf
    Že by konečně náznak nové kosmologie / nové fyziky?
    VIRGO
    VIRGO --- ---
    Odhalování galaktických tajemství | ESO Česko
    https://www.eso.org/public/czechrepublic/news/eso1734/?lang

    Zooming in on the galaxy NGC 1316
    https://www.youtube.com/watch?v=hFboxodn7ZM


    Na obřím snímku, který zachycuje kupu galaxií v souhvězdí Pece, upoutá naši pozornost nespočet galaxií. Některé vypadají jen jako drobné tečky v pozadí,
    ale jiné dominují celému popředí záběru. Jedním z velkých objektů je hojně zkoumaná čočková galaxie NGC 1316. Bouřlivá minulost zanechala nápadné šrámy
    na jejím současném vzhledu – struktury smyček, oblouků a prstenů, které se nyní astronomům pomocí dalekohledu VST podařilo zachytit v jemnějších detailech,
    než bylo dosud možné. Tento pozoruhodně hluboký snímek rovněž odhaluje myriády slabších objektů.

    VIRGO
    VIRGO --- ---
    A super-precise measurement shows proton and antiproton have identical magnetic properties

    Universe shouldn’t exist, CERN physicists conclude | Cosmos
    https://cosmosmagazine.com/physics/universe-shouldn-t-exist-cern-physicists-conclude

    One of the great mysteries of modern physics is why antimatter did not destroy the universe at the beginning of time.

    To explain it, physicists suppose there must be some difference between matter and antimatter – apart from electric charge.
    Whatever that difference is, it’s not in their magnetism, it seems.

    Physicists at CERN in Switzerland have made the most precise measurement ever of the magnetic moment of an anti-proton –
    a number that measures how a particle reacts to magnetic force – and found it to be exactly the same as that of the proton
    but with opposite sign. The work is described in Nature.
    VIRGO
    VIRGO --- ---
    http://www.aei.mpg.de/2147555/stronger-tests-of-einstein-s-relativity

    Combining gravitational-wave observations and pulsar timing to study alternatives to the theory of general relativity

    Einstein's theory of general relativity has withstood 100 years of experimental scrutiny. However, these tests do not constrain how well the very strong gravitational fields
    produced by merging neutron stars obey this theory. New, more sophisticated techniques can now search for deviations from general relativity with unprecedented sensitivity.
    Scientists at the Max Planck Institutes for Gravitational Physics and for Radio Astronomy studied two foremost tools for testing the strong-field regime of gravity – pulsar
    timing and gravitational-wave observations – and demonstrated how combining these methods can put alternative theories of general relativity to the test.

    VIRGO
    VIRGO --- ---
    +1
    Jiří Grygar - Boj s lidskou hloupostí se nedá vyhrát | Neurazitelny.cz | Večery na FF UK
    https://www.youtube.com/watch?v=OI9-dNu9iz0
    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/image-feature/goddard/2017/hubble-unravels-a-twisted-cosmic-knot

    NGC 2623 gained its unusual and distinctive shape as the result of a major collision and subsequent merger between two separate galaxies.
    This violent encounter caused clouds of gas within the two galaxies to become compressed and stirred up, in turn triggering a sharp spike
    of star formation. This active star formation is marked by speckled patches of bright blue; these can be seen clustered both in the center
    and along the trails of dust and gas forming NGC 2623’s sweeping curves (known as tidal tails). These tails extend for roughly 50 000 light-
    years from end to end. Many young, hot, newborn stars form in bright stellar clusters — at least 170 such clusters are known to exist within
    NGC 2623.

    VIRGO
    VIRGO --- ---
    +3
    Vegetation Index of Earth with MapCam Color Image Overlaid - OSIRIS-REx Mission
    https://www.asteroidmission.org/vegindexcolorcompfadein/

    This vegetation index, created using images taken by OSIRIS-REx’s MapCam camera on Sept. 22, 2017, shows areas on Earth with abundant plant life.
    The overlay fading in is a color composite image captured by MapCam the same day. The bright green areas have higher densities of trees and other
    plants, and the darker green areas have lower densities. Hawaii stands out against the Pacific Ocean in the middle of the image. Australia, New
    Zealand and Papua New Guinea are visible in the lower left, and parts of China, Japan and Korea appear in the upper left.

    VIRGO
    VIRGO --- ---
    +4
    Scientist sees evidence of planet formation in narrow rings of other solar systems
    https://phys.org/news/2017-10-scientist-evidence-planet-formation-narrow.html

    Narrow dense rings of comets are coming together to form planets on the outskirts of at least
    three distant solar systems, astronomers have found in data from a pair of NASA telescopes.

    VIRGO
    VIRGO --- ---
    +1
    https://www.nasa.gov/feature/nasa-receives-findings-from-wfirst-independent-review-team

    NASA has received the report from an independent, external review of the Wide Field Infrared Survey Telescope (WFIRST) project. The review
    was commissioned by NASA to help ensure that the mission is well understood in terms of scope and required resources, and is executable.

    https://www.nasa.gov/sites/default/files/atoms/files/final-wietr_memo-signed-171019.pdf

    VIRGO
    VIRGO --- ---
    An Atmosphere Around the Moon? Research Indicates Yes | NASA
    https://www.nasa.gov/...nd-the-moon-nasa-research-suggests-significant-atmosphere-in-lunar-past.html

    Looking up at the Moon at night, Earth’s closest neighbor appears in shades of gray and white; a dry desert in the vacuum of space,
    inactive and dead for billions of years. Like many things, though, with the Moon, there is so much more than what meets the eye.

    Research completed by NASA Marshall Space Flight Center planetary volcanologist Debra Needham in Huntsville, Alabama, and planetary
    scientist David Kring at the Lunar and Planetary Institute in Houston, Texas, suggests that billions of years ago, the Moon actually
    had an atmosphere. The ancient lunar atmosphere was thicker than the atmosphere of Mars today and was likely capable of weathering
    rocks and producing windstorms. Perhaps most importantly, it could be a source for some, if not all, of the water detected on the Moon.

    VIRGO
    VIRGO --- ---
    Armagh Observatory
    http://star.arm.ac.uk/press/2017/MarsTr_Oct17_pr.html

    The planet Mars shares its orbit with a handful of small asteroids, the so-called Trojans. Among them, one finds a unique group, all moving in very similar orbits,
    suggesting that they originated from the same object. But the mechanism that produced this "family" has been a mystery. Now, an international team of astronomers
    believe they have identified the culprit: sunlight. Their findings, which highlight how small asteroids near the Sun may evolve, are to be presented at the annual
    Meeting of the Division of Planetary Sciences of the American Astronomical Society at Provo, Utah this week, by Dr. Apostolos Christou, a Research Astronomer at
    the Armagh Observatory and Planetarium in Northern Ireland, United Kingdom and leader of the research team.

    VIRGO
    VIRGO --- ---
    https://www.nasa.gov/content/goddard/hubble-s-messier-catalog

    While the Hubble Space Telescope has not produced images of every object in the Messier catalog, it has observed 93 of them as of August 2017.
    Some of Hubble's photographs offer views of a given object in its entirety, but many focus on specific areas of interest. While Hubble is able
    to magnify objects very effectively, it has a relatively small field of view. This means that, in some cases, Hubble would need to take many
    exposures to capture an entire object. Although this is not always an efficient use of its time, as is the case for the widely spaced “open”
    star clusters in the Messier catalog, many exposures are taken when the scientific value justifies the time spent. One of these objects is the
    Andromeda galaxy (designated M31 in Messier’s catalog). In order to create a mosaic image that depicts almost half of Andromeda, Hubble has
    taken nearly 7,400 exposures of the galaxy.

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