Skip to main content

Home/ Astronomy/ Group items tagged Star

Rss Feed Group items tagged

Filter: All | Bookmarks | Topics Simple Middle
Sandra Flores

Archaeology in the universe - 0 views

image

started by Sandra Flores on 30 Oct 14 no follow-up yet
Kalyan Roy

Why Are Quark Stars So Strange? : Discovery News - 1 views

news.discovery.com/...re-quark-stars-so-strange.html

Astronomy

shared by Kalyan Roy on 20 Jan 10 - Cached
  • First things first, neutron stars, quark stars and black holes are all born via the same mechanism: a supernova. But each of the three are progressively more massive, so they originate from supernovae produced by progressively more massive stars. So, what if a star exploded, producing something a little too massive to be called a neutron star? Well, neutron stars resist collapsing under their own gravitational pull by a characteristic of matter known as neutron degeneracy. This produces an outward force called neutron degeneracy pressure. What if the neutron star born after a supernova is too massive for this neutron degeneracy pressure to hold up against the neutron star's own gravity? In this case, it's up to the quarks that make up the neutrons to take over, preventing the body from collapsing any further. Single neutrons are composed of three quarks (two "down" quarks and one "up" quark). When quark degeneracy pressure kicks in, a quark star may be produced; the free "up" and "down" quarks get converted into "strange" quarks. Therefore, a quark star (also known as a "strange star") is made up of strange matter.
  • Using what we know from the Standard Model of particle physics, a massive quark star may have enough gravitational energy to start 'burning' strange matter. The quarks inside the core of the quark star may be abused so badly by gravitational pressure that the quarks will be converted into pure energy and neutrinos.
  • The fascinating thing with this scenario is that the quark star matter will be so dense that even the neutrinos cannot escape. However, this release of energy and generation of neutrinos creates an outward pressure countering the relentless inward gravitational pull.
  • ...2 more annotations...
  • Dai calls this extreme strange matter-burning quark star an "electroweak star"
  • Saving the best till last, the electroweak star's core would therefore be as extreme as the universe was only 10-10 seconds (that's 0.0000000001 seconds) after the Big Bang. These extreme objects would be like mini-Big Bang laboratories, maintaining a pressure where the electromagnetic and weak forces are so intertwined, they cannot be distinguished.
Sandra Flores

Star Formation - 0 views

Heated gas stream at a cool star formation?In the inner regions of a galaxy cluster, astronomers found by Michael McDonald from the Massachusetts Institute of Technology in the USA further evidence...

stars cosmos astronomy

started by Sandra Flores on 02 Nov 14 no follow-up yet
Janos Haits

Chrome Experiments - "100,000 Stars" by Google Data Arts Team - 3 views

www.chromeexperiments.com/...100000-stars

astronomy stars science space planetary galactic cosmology universe chrome

shared by Janos Haits on 01 Aug 13 - No Cached
  • Janos Haits on 01 Aug 13
     
    100,000 Stars is an interactive visualization of the stellar neighborhood created for the Google Chrome web browser. It shows the real location of over 100,000 nearby stars. Zooming in reveals 87 major named stars and our solar system. The galaxy view is an artist's rendition.
Sandra Flores

Strange stars on the heel - 0 views

Strange stars on the heelA new star strange lurks perhaps in our galaxy - and an astrophysicist at the Weizmann Institute is close on the track. Prof. Vladimir Usov from the Weizmann Institute...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Sandra Flores

Strange stars on the heel - 0 views

Strange stars on the heelA new star strange lurks perhaps in our galaxy - and an astrophysicist at the Weizmann Institute is close on the track. Prof. Vladimir Usov from the Weizmann Institute...

started by Sandra Flores on 09 Jan 15 no follow-up yet
Learn Astronomy

REGULUS BINARY STAR SYSTEM - 1 views

In a starry night with clear skies above us, we see beautiful stars dotted with the sky. Many of these stars can be easily recognized. Regulus is one of them. Regulus looks like a single star to th...

started by Learn Astronomy on 20 Jan 21 no follow-up yet
Sandra Flores

Revealing pattern without planets - 0 views

Revealing pattern without planets Planets around young suns are formed in a disk of gas and dust orbiting the star just created. Many such disks have now been detected around young stars. In some y...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Janos Haits

Welcome to the NASA Star and Exoplanet Database - 1 views

nsted.ipac.caltech.edu

nasa database Astronomy science universe planetary cosmology space

shared by Janos Haits on 23 Aug 11 - No Cached
  • Janos Haits on 23 Aug 11
     
    he NASA Star and Exoplanet Database (NStED) collects and serves public data to support the search for and characterization of extra-solar planets (exoplanets) and their host stars. The data include published light curves, images, spectra and parameters, and time-series data from surveys that aim to discover transiting exoplanets. All data are validated by the NStED science staff and traced to their sources. NStED is the U.S. data portal for the CoRoT mission.
Sandra Flores

How big are neutron stars? - 0 views

How big are neutron stars?With the help of X-ray pulses can soon be determined by the diameter of neutron stars.Neutron stars are in the list of the most remarkable celestial body is a one of the t...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Sandra Flores

Planetary Nebulae - 0 views

Hubble Gallery of planetary nebulaeSo far, the end of a sun-like star was regarded as a fairly simple process: The star gets rid of dignified a shell glowing gas and then settles down to a long ret...

started by Sandra Flores on 05 Jan 15 no follow-up yet
Sandra Flores

How big are neutron stars? - 0 views

How big are neutron stars?With the help of X-ray pulses can soon be determined by the diameter of neutron stars.Neutron stars are in the list of the most remarkable celestial body is a one of the t...

started by Sandra Flores on 09 Jan 15 no follow-up yet
Sandra Flores

Planetary Nebulae - 0 views

Hubble Gallery of planetary nebulaeSo far, the end of a sun-like star was regarded as a fairly simple process: The star gets rid of dignified a shell glowing gas and then settles down to a long ret...

started by Sandra Flores on 09 Jan 15 no follow-up yet
Janos Haits

Star Shadows Remote Observatory Home Page - 1 views

www.starshadows.com

star shadows remote observatory Astronomy Science space cosmology planetary universe galactic

shared by Janos Haits on 05 Apr 12 - No Cached
  • Janos Haits on 05 Apr 12
     
    Located at New Mexico Skies and CTIO, Star Shadows Remote Observatory (SSRO) is a cooperative astro-imaging venture operated by Lewis Garrett, Jacob Gerritsen, Rick Gilbert,  Jack Harvey, Steve Mazlin, Michael Smith, Teri Smoot, and Daniel Verschatse.
Todd Suomela

Astronomers Crowdsource the Definition of a Galaxy - Technology Review - 2 views

www.technologyreview.com/...26292

citizen-science crowdsourcing science astronomy galaxies galactic classification definition taxonomy

shared by Todd Suomela on 05 Feb 11 - No Cached
  • So what to do? Today, Duncan Forbes at Swinburne University in Australia and Pavel Kroup at the University of Bonn in Germany put forward a novel solution. They outline the various characteristics that astronomers think about when classifying galaxies. These include factors such as the presence of stars, so gas clouds can't be defined as galaxies; being gravitationally bound, so materials that has been stripped away by another galaxy wouldn't count; whether the system is stable or not; whether it hosts a good variety of different types of star, which excludes globular clusters which contain only similar stars; and whether it is held together by dark matter, which many galaxies seem to be. There are other factors too, of course. (Although they do not include the presence of a black hole at the centre of a galaxy as a defining characteristic , which is odd given the growing interest in the link between galactic evolutoin and black holes.) Forbes and Kroup go on to suggest that the best way to achieve consensus is to crowdsource the problem. In other works, they want to use the wisdom of the crowd to determine what factors are important what aren't.
1 - 20 of 86 Next › Last »
Showing 20▼ items per page