Tento web používá soubory cookie. Dalším používáním webu s tímto souhlasíte.
jméno
heslo
přihlásit
zaregistrujte se
zapomněli jste heslo?
Cosmos In Brief - Aktualní novinky vesmírného výzkumu v kostce
VIRGO
Máte k tomu co říct? Vložte se do diskuze.
VIRGO --- 19:40:18 19.9.2017
Forming Planetesimals in a Dust and Gas Vortex
http://aasnova.org/2017/09/19/forming-planetesimals-in-a-dust-and-gas-vortex/

Planet formation still holds many mysteries for today’s astronomers. One of the biggest unknown is how pebbles and dust clump together to form planetesimals
rather than drifting in towards the star due to its strong gravitational pull. A possible solution is dust traps — in a circumstellar disk, the inward drift
of the pebbles and particles can be stopped by high pressure in the gaseous disk. A dust trap like this would be an ideal place to form planetesimals. The
authors of today’s paper look at a circumstellar disks around AB Aur. They create hydrodynamical simulations of the dust and gas to see if there is a dust
trap with the possible formation of small planets.

Circumstellar disks are the link between bunches of dust around a star and fully formed planetesimals. There are a few types of circumstellar disks —
protoplanetary, transition, and debris. A transition disk is exactly what it sounds like — a transition from protoplanetary to debris, which means that
planets would likely be forming in a transition disk. About 450 light-years away from us, AB Aur hosts an asymmetric transition disk. The unevenness of ¨
the disk could indicate a dust trap or gas vortex. At about 120 AU from the central star, the cold dust emission disk creates an asymmetric ring in the disk.

[http://aasnova.org/wp-content/uploads/2017/09/fig3-2.jpg]
VIRGO --- 19:30:54 19.9.2017
Nanosat fleet proposed for voyage to 300 asteroids – Europlanet Outreach
http://www.europlanet-eu.org/nanosat-fleet-proposed-to-300-asteroids/

A fleet of tiny spacecraft could visit over 300 asteroids in just over three years, according to a mission study led by the Finnish Meteorological Institute.
The Asteroid Touring Nanosat Fleet concept comprises 50 spacecraft propelled by innovative electric solar wind sails (E-sails) and equipped with instruments
to take images and collect spectroscopic data on the composition of the asteroids. Each nanosat would visit six or seven asteroids before returning to Earth
to deliver the data. The concept will be presented by Dr Pekka Janhunen at the European Planetary Science Congress 2017 in Riga on Tuesday 19th September.

[http://www.europlanet-eu.org/wp-content/uploads/2017/09/fig32a-768x727.png]
VIRGO --- 19:25:53 19.9.2017
Expect the unexpected from the big-data boom in radio astronomy
https://theconversation.com/expect-the-unexpected-from-the-big-data-boom-in-radio-astronomy-84059

Radio astronomy is undergoing a major boost, with new technology gathering data on objects in our universe faster than astronomers can analyse.

Expect the unexpected from the big-data boom in radio astronomy
https://www.youtube.com/watch?v=VfDcTp5cqlI


[https://theconversation.imgix.net/files/186309/original/file-20170918-27951-19m8q3b.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754]
VIRGO --- 17:59:22 19.9.2017
Size matters in the detection of exoplanet atmospheres – Europlanet Outreach
http://www.europlanet-eu.org/size-matters-in-the-detection-of-exoplanet-atmospheres/

A group-analysis of 30 exoplanets orbiting distant stars suggests that size, not mass, is a key factor
in whether a planet’s atmosphere can be detected. The largest population-study of exoplanets to date
successfully detected atmospheres around 16 ‘hot Jupiters’, and found that water vapour was present
in every case.

[http://www.europlanet-eu.org/wp-content/uploads/2017/09/exoplanet-3-768x522.jpg]
VIRGO --- 17:56:35 19.9.2017
ESA Science & Technology: The cosmic water trail uncovered by Herschel
http://sci.esa.int/herschel/59494-the-cosmic-water-trail-uncovered-by-herschel/

ESA's Herschel Space Observatory, an extraordinary mission that was launched in 2009 and that observed the sky at far-infrared
and sub-millimetre wavelengths for almost four years, took a comprehensive approach, tracing water from stars and planets in
the forming across our Milky Way galaxy to planets and minor Solar System bodies in our own neck of the woods.

Herschel: water
https://www.youtube.com/watch?v=z0mpVrFYOMM
VIRGO --- 16:14:02 19.9.2017
New mirror-coating technology promises dramatic improvements in telescopes
https://news.ucsc.edu/2017/09/mirror-coating.html

Materials scientist Nobuhiko Kobayashi wasn't quite sure why the astronomer he met at a wine-tasting several years
ago was so interested in his research, but as he learned more about telescope mirrors it began to make sense.

[https://news.ucsc.edu/2017/09/images/drew-nobby-dave-410.jpg]
VIRGO --- 16:09:33 19.9.2017
VLASS:
VLA Begins Huge Project of Cosmic Discovery – National Radio Astronomy Observatory
https://public.nrao.edu/news/vla-begins-huge-project/

Astronomers have embarked on the largest observing project in the more than four-decade history of the National Science Foundation’s
Karl G. Jansky Very Large Array (VLA) — a huge survey of the sky that promises a rich scientific payoff over many years.

Over the next 7 years, the iconic array of giant dish antennas in the high New Mexico desert will make three complete scans of the sky
visible from its latitude — about 80 percent of the entire sky. The survey, called the VLA Sky Survey (VLASS), will produce the sharpest
radio view ever made of such a large portion of the sky, and is expected to detect 10 million distinct radio-emitting celestial objects,
about four times as many as are now known.

[https://public.nrao.edu/wp-content/uploads/2017/09/nrao17df09a-1170x600.jpg]
VIRGO --- 15:56:03 19.9.2017
Chandra :: Photo Album :: V745 Sco :: September 18, 2017
http://chandra.harvard.edu/photo/2017/v745/

A new 3D model of an explosion from the V745 Sco system is helping astronomers learn more about this volatile system.

V745 Sco is a binary system where a red giant and a white dwarf star are in very close orbit around one another.

A Quick Look at V745 Sco
https://www.youtube.com/watch?v=MJZU15yg5cQ


The intense gravitational forces from the white dwarf pull the outer layers of the red dwarf onto the smaller star’s surface, triggering explosions.

Astronomers observed V745 Sco about two weeks after its most recent outburst in 2014 with Chandra, enabling them to generate this new 3D model.

[http://chandra.harvard.edu/photo/2017/v745/v745_labeled_525.jpg]
VIRGO --- 15:41:49 19.9.2017
New quasar discovered by astronomers
https://phys.org/news/2017-09-quasar-astronomers.html

A team of astronomers led by Jacob M. Robertson of the Austin Peay State University in Clarksville, Tennessee has detected
a new quasi-stellar object (QSO). They found the new quasar, designated SDSS J022155.26-064916.6, as a result of an analysis
of available spectroscopic data. The finding is reported in a paper published Sept. 10 on the arXiv pre-print server.

To date, astronomers have identified more than 200,000 quasars, most of them from the Sloan Digital Sky Survey (SDSS). SDSS
is an imaging and spectroscopic redshift survey, which utilizes the 2.5-m wide-angle optical telescope at the Apache Point
Observatory (APO) located in New Mexico. It is regarded as one of the most successful astronomical surveys, having produced
the most detailed three-dimensional maps of the universe ever made.

Now, a group of researchers led by Robertson reports the discovery of another quasar from the SDSS data. They found that the
object known as SDSS J022155.26-064916.6, which was initially imaged by SDSS and classified as a star with a cosmic ray hit,
is in fact a quasar at redshift of about 0.8.

[1709.03166] Discovery of a New Quasar: SDSS J022155.26-064916.6
https://arxiv.org/abs/1709.03166

[https://3c1703fe8d.site.internapcdn.net/newman/csz/news/800/2017/newquasardis.jpg]
HERRICH --- 9:30:19 17.9.2017
https://www.nasa.gov/feature/goddard/2017/hubble-captures-blistering-pitch-black-planet

NASA's Hubble Space Telescope has observed a planet outside our solar system that looks as black as fresh asphalt because it eats light rather than reflecting it back into space. This light-eating prowess is due to the planet's unique capability to trap at least 94 percent of the visible starlight falling into its atmosphere.

[https://www.nasa.gov/sites/default/files/thumbnails/image/hubblestscihp1738af4500x3600.jpg]