Gourt > Science > Astronomy > Stars > Binary Stars
A binary star is a stellar system consisting of two stars orbiting around their center of mass. For each star, the other is its companion star. Recent research suggests that a large percentage of stars are part of systems with at least two stars. Binary star systems are very important in astrophysics, because observing their mutual orbits allows their mass to be determined. The masses of many single stars are then determined by extrapolations made from the observation of binaries.
Binary stars are not the same as optical double stars, which appear to be close together as seen from Earth, but may not be bound by gravity. Binary stars can either be distinguished optically (visual binaries) or by indirect techniques, such as spectroscopy. If binaries happen to orbit in a plane containing our line of sight, they will eclipse each other; these are called eclipsing binaries.
The components of binary star systems can exchange mass, bringing their evolution to stages that single stars cannot attain. Examples of binaries are Algol (an eclipsing binary), Sirius, and Cygnus X-1 (of which one member is probably a black hole).
More on [ Binary star ]
GeoEye-1 Will Be A High-Res Eye In The Sky
Fri, 29 Aug 2008 14:29:00 -0400
The GeoEye-1 satellite will be capable of making out details on Earth just 16 inches across. It will be the highest resolution satellite run by a private company; it's images will be marketed to a range of governments and private customers.
Europe Considers Joining Space-Faring Nations
Tue, 19 Aug 2008 10:35:00 -0400
Europe's space agency reached two milestones earlier this year. A European-built lab was installed at the International Space Station, and Europe launched a robotic cargo vehicle that successfully docked with the station. The European Space Agency is thinking about converting the vehicle so it could take astronauts into orbit.
Tensions With Russia May Hurt NASA Program
Fri, 15 Aug 2008 16:18:00 -0400
The conflict with Russia over Georgia might affect NASA's ability to get astronauts to the international space station after the space shuttle gets retired in 2010. Congress must pass a special waiver by Sept. 30 so NASA can buy Soyuz capsule flights.
What Makes Our Solar System Special?
Fri, 08 Aug 2008 15:02:00 -0400
Researchers say that if the conditions had been slightly different for our solar system, planets could have careened into the sun or been expelled into deep space. Also: A volunteer astronomer spots a strange gaseous object some are calling a "cosmic ghost."
Phoenix Finds A Salt Compound On Mars
Fri, 08 Aug 2008 14:07:00 -0400
NASA's Phoenix Mars Lander has detected a salt found on Earth on the surface of Mars. The salt, called perchlorate, is used in fireworks and rocket fuel. The news follows the recent confirmation of the presence of water on the Red Planet.
Space Company Hopes To Cut Cost Of Launches
Thu, 07 Aug 2008 16:44:00 -0400
A private company called SpaceX has failed three times to reach orbit with one of its rockets. But the company says it's learning from its failures and still hopes to radically decrease the cost of putting objects in space.
Astronomical League Double Star Club - The purpose of the Double Star Club is to introduce observers to 100 of the finest double and multiple stars in the heavens.
Astronomy 101/103 Web Simulations - Includes two JAVA simulations of binary star systems.
Binary Star Simulation - This is a representation of the binary star on a graphical and easy way.
Binary Stars Astronomy Lecture - A single introductory astronomy lecture on Binary Stars, including several useful diagrams.
Double Stars to Follow - A five-part article by Martin Gaskell of the Prairie Astronomy Club.
Eclipsing Binary Stars - Information on binary stars and links to online articles.
Hubble Separates Stars In The Mira Binary System - Hubble Space Telescope News Release/Paper about the discovery of the atmospheric interaction between the giant star Mira and its white dwarf companion star.
Interacting Binary Stars - Nice click-through tour with some great animations about some of the complexities of Binary Systems.
International Astronomical Union - Organization based in Hungary that studies binary stars.
Mass Transfer in the Binary Star Algol - This site shows the dynamic hydrodynamic models have shown that the circumstellar flow in Algol is relatively independent of the initial speed and direction of the tidal stream. Rather, the flow dynamics are determined primarily by the strength of radiative cooling, which depends on the density of the gas in the mass transfer stream.
On The Mechanics of Star Formation - Binary Stars and Nemesis - Brief scientific paper on accretion disk polar jetting by Max Domaschko, PhD, So. Charleston, WV, USA. Also links to a small page of hubble photographs of jetstreams from young stars.
The Binary Pulsar: PSR 1913+16 - Information on the PSR 1013+16 pulsar, a part of a binary system, the discoverers of which won the Nobel Prize in 1993.
The Double Star Library - The Double Star Library hopes to be a means by which various types of binary and multiple star information can be easily disseminated among binary star astronomers in IAU Commission 26 and related commissions.
The Formation of Binary Stars - Recent observational investigations of the frequency of occurrence of pre-main-sequence binary stars have reinforced earlier suspicions that binary formation is the primary branch of the star-formation process
The Prosper Project - Observation program targeted to understand eclipsing binaries without known light ephemeris.
| of stars with eccentric orbits... All images shown have been done using real data about known binary star systems. ... 3d ... | |
| Next Video | |
