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    VIRGOCosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce




    For every complex question, there's a simple answer that's completely wrong.
    rozbalit záhlaví
    JULIANNE
    JULIANNE --- ---
    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 --- ---
    VIRGO
    VIRGO --- ---
    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 --- ---
    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 --- ---
    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 --- ---
    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 --- ---
    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 --- ---
    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.

    VIRGO
    VIRGO --- ---
    News | Deep Space Communications via Faraway Photons
    https://www.jpl.nasa.gov/news/news.php?feature=6967

    A spacecraft destined to explore a unique asteroid will also test new communication hardware that uses lasers instead of radio waves.

    The Deep Space Optical Communications (DSOC) package aboard NASA's Psyche mission utilizes photons -- the fundamental particle of visible
    light -- to transmit more data in a given amount of time. The DSOC goal is to increase spacecraft communications performance and efficiency
    by 10 to 100 times over conventional means, all without increasing the mission burden in mass, volume, power and/or spectrum.

    Tapping the advantages offered by laser communications is expected to revolutionize future space endeavors - a major objective of NASA's
    Space Technology Mission Directorate (STMD).

    The DSOC project is developing key technologies that are being integrated into a deep space-worthy Flight Laser Transceiver (FLT), high-tech
    work that will advance this mode of communications to Technology Readiness Level (TRL) 6. Reaching a TRL 6 level equates to having technology
    that is a fully functional prototype or representational model.

    VIRGO
    VIRGO --- ---
    Fermi Gamma-ray Burst Monitor Wakes the World to Smashing Stars | NASA
    https://www.nasa.gov/...fermi-gamma-ray-burst-monitor-wakes-the-world-to-smashing-neutron-stars.html

    An Ordinary Gamma-ray Burst with Extraordinary Consequences
    https://www.youtube.com/watch?v=nfWKBo2i8Dk
    VIRGO
    VIRGO --- ---
    https://lowell.edu/spinning-comet/

    Astronomers at Lowell Observatory observed comet 41P/Tuttle-Giacobini-Kresak last spring and noticed that the speed of its rotation was quickly slowing down.
    A research team led by David Schleicher studied the comet while it was closer to the Earth than it has ever been since its discovery. The comet rotational
    period became twice as long, going from 24 to more than 48 hours within six weeks, a far greater change than ever observed before in a comet. If it continues
    to slow down, it might stop completely and then begin rotating in the opposite direction.

    VIRGO
    VIRGO --- ---
    Samples brought back from asteroid reveal ‘rubble pile’ had a violent past - News and Events | Curtin University, Perth, Western Australia
    http://news.curtin.edu.au/...releases/samples-brought-back-asteroid-reveal-rubble-pile-violent-past/

    Curtin University planetary scientists have shed some light on the evolution of asteroids,
    which may help prevent future collisions of an incoming ‘rubble pile’ asteroid with Earth.

    The scientists studied two incredibly small particles brought back to Earth from the asteroid
    Itokawa, after they were collected in 2005 from the surface of the 500 metre-wide asteroid,
    by the Japanese Hayabusa spacecraft.

    The Geology-published research, Collisional history of asteroid Itokawa, used the Argon-Argon
    dating technique to investigate when impact crater events happened on Itokawa, offering a glimpse
    into the asteroid’s impact history.

    VIRGO
    VIRGO --- ---
    Cassini: The Grand Finale: NASA Team Finds Noxious Ice Cloud on Saturn’s Moon Titan
    https://saturn.jpl.nasa.gov/news/3128/nasa-team-finds-noxious-ice-cloud-on-saturns-moon-titan/

    Researchers with NASA’s Cassini mission have found evidence of a toxic hybrid ice in a wispy cloud high above the south pole of Saturn’s largest moon, Titan.
    The finding is a new demonstration of the complex chemistry occurring in Titan’s atmosphere—in this case, cloud formation in the giant moon’s stratosphere—and
    part of a collection of processes that ultimately helps deliver a smorgasbord of organic molecules to Titan’s surface.

    VIRGO
    VIRGO --- ---
    SwRI scientists dig into the origin of organics on Ceres | SwRI
    http://www.swri.org/press-release/swri-scientists-dig-origin-organics-ceres

    Since NASA’s Dawn spacecraft detected localized organic-rich material on Ceres, Southwest Research Institute (SwRI) has been digging into the data to explore different scenarios
    for its origin. After considering the viability of comet or asteroid delivery, the preponderance of evidence suggests the organics are most likely native to Ceres.

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