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Cosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
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VIRGO --- 23:15:04 30.11.2015
Cosmic Cryptography
Often “random” numbers are only pseudo-random. They look like random numbers, but use a particular algorithm to simulate randomness.
To get better random numbers, you can use thermal fluctuations in your computer, or noise in weather data. Or, as in the case of a new paper,
data from the cosmic microwave background. It might seem like the CMB is a really bad choice. After all, it can be seen by everyone, so if
you use CMB data to create a random number why can’t someone else get the same number? But it turns out that’s not a problem.
The basic idea is to take a patch of sky and measure the distribution of energy from the CMB, specifically what’s known as the power spectrum.
That spectrum is then compared to the theoretical ideal, and the difference creates a random number. Even if someone measured exactly the same
patch of sky, they wouldn’t get the exact same result, and therefore wouldn’t get the same number. While the authors use the CMB as an example,
they point out a similar method could be used to generate random numbers from the 21 centimeter line, supernova remnants, radio galaxies and
other astrophysical phenomena. All you need is a basic radio telescope, and you have a random number generator.
It’s not likely that this astrophysical method is any better than what we use now. Thermal variations and weather patterns are pretty random
as it is. But it’s an interesting idea to use the secrets of the universe to keep your own secrets.
VIRGO --- 21:36:27 30.11.2015
Simulation Shows Key to Building Powerful Magnetic Fields | Caltech
When certain massive stars use up all of their fuel and collapse onto their cores, explosions 10 to 100 times brighter
than the average supernova occur. Exactly how this happens is not well understood. Astrophysicists from Caltech, UC Berkeley,
the Albert Einstein Institute, and the Perimeter Institute for Theoretical Physics have used the National Science Foundation's
Blue Waters supercomputer to perform three-dimensional computer simulations to fill in an important missing piece of our
understanding of what drives these blasts.

VIRGO --- 21:28:34 30.11.2015
Researchers employ supercomputers to create three-dimensional models of planetary storms
Simulating the jet streams and anticyclones of Jupiter and Saturn | EurekAlert! Science News
A University of Alberta researcher has successfully generated 3D simulations of deep jet streams and storms on Jupiter and Saturn,
helping to satiate our eternal quest for knowledge of planetary dynamics. The results facilitate a deeper understanding of planetary
weather and provide clues to the dynamics of Earth's weather patterns evidenced in jet streams and ocean currents.

VIRGO --- 20:57:13 30.11.2015
NASA's Webb "Pathfinder Telescope" Successfully Completes Second Super-Cold Optical Test
Recently, the James Webb Space Telescope's "pathfinder telescope," or “Pathfinder” completed its second super-cold optical test
that resulted in the first checkout of specialized optical test equipment designed to illuminate the telescope’s optics through
to the instrument focal planes, and the procedures used to operate this test equipment.

VIRGO --- 19:03:52 30.11.2015
New comet shape model | Rosetta - ESA's comet chaser
A new 3D shape model of Comet 67P/Churyumov-Gerasimenko has been released by ESA’s Rosetta archive
team today. The model includes images taken by Rosetta’s NAVCAM up until mid-late July 2015, and
reveals parts of the comet’s southern hemisphere that were not included in earlier shape models.
Interaktivní 3D: http://imagearchives.esac.esa.int/index.php?/page/navcam_3d_models

VIRGO --- 16:49:47 30.11.2015
European Space Agency, ESA
Tracking down under: take a look at images of our new 4.5m high-tech dish
antenna in New Norcia, Australia, part of the Estrack network.

VIRGO --- 16:29:24 30.11.2015
European payload selected for ExoMars 2018 surface platform / Space Science / Our Activities / ESA
Two European instruments and four European contributions on two Russian instruments have been selected for
the Russian-led science platform that will land on Mars as part of the ESA–Roscosmos ExoMars 2018 mission.
The first of the two ExoMars mission is in final preparation for launch next March. It consists of the Trace
Gas Orbiter, which will investigate the possible biological or geological origins of important trace gases
in the martian atmosphere, and Schiaparelli, an entry, descent and landing demonstrator module.
Schiaparelli will test key landing technologies and provide atmospheric and environmental data important
for ESA’s contributions to subsequent missions to Mars.

VIRGO --- 16:08:48 30.11.2015
NOVA | Invisible Universe Revealed - PBS Documentary 2015
VIRGO --- 15:48:11 30.11.2015
Bristol University | News | November: Earth’s first ecosystems
Computer simulations have allowed scientists to work out how a puzzling 555-million-year-old organism with no known modern relatives fed,
revealing that some of the first large, complex organisms on Earth formed ecosystems that were much more complex than previously thought.

The international team of researchers from Canada, the UK and the USA, including Dr Imran Rahman from the University of Bristol, studied
fossils of an extinct organism called Tribrachidium, which lived in the oceans some 555 million years ago. Using a computer modelling
approach called computational fluid dynamics, they were able to show that Tribrachidium fed by collecting particles suspended in water.
This is called suspension feeding and it had not previously been documented in organisms from this period of time.
Tribrachidium lived during a period of time called the Ediacaran, which ranged from 635 million to 541 million years ago. This period
was characterised by a variety of large, complex organisms, most of which are difficult to link to any modern species. It was previously
thought that these organisms formed simple ecosystems characterised by only a few feeding modes, but the new study suggests they were
capable of more types of feeding than previously appreciated.