Double star
hideIn observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because the pair forms a binary system of stars in mutual orbit, gravitationally bound to each other, or because it is an optical double, a chance alignment of two stars in the sky that lie at different distances. Binary stars are important to stellar astronomers as knowledge of their motions allows direct calculation of stellar mass and other stellar parameters.
Since the beginning of the 1780s, both professional and amateur double star observers have telescopically measured the distances and angles between double stars to determine the relative motions of the pairs. If the relative motion of a pair determines a curved arc of an orbit, or if the relative motion is small compared to the common proper motion of both stars, it may be concluded that the pair is in mutual orbit as a binary star. Otherwise, the pair is optical. Multiple stars are also studied in this way, although the dynamics of multiple stellar systems are more complex than those of binary stars.
For more information about Double star, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with double stars
Radio telescope images reveal planet-forming disk orbiting twin suns
Jun 10, 2009 |
4.3 / 5 (10) |
2
Astronomers are announcing today that a sequence of images collected with the Smithsonian's Submillimeter Array (SMA) clearly reveals the presence of a rotating molecular disk orbiting the young binary star ...
Astronomers spot cosmic dust fountain
Feb 05, 2009 |
4.7 / 5 (12) |
0
(PhysOrg.com) -- Space dust annoys astronomers just as much as the household variety when it interferes with their observations of distant stars. And yet space dust also poses one of the great mysteries of ...
Jupiter-like planets could form around twin suns
Jan 05, 2009 |
4 / 5 (5) |
0
(PhysOrg.com) -- Life on a planet ruled by two suns might be a little complicated. Two sunrises, two sunsets. Twice the radiation field.
Search results for double stars
'Avatar' video game to expand film's alien world
10 hours ago |
4 / 5 (1) |
0
(AP) -- James Cameron was thinking beyond the big screen when he created the alien world of Pandora. The "Titanic" director worked in tandem with video game developer Ubisoft Montreal on the game based on ...
Herschel takes a peek at the ingredients of the galaxies
10 hours ago |
4.5 / 5 (4) |
0
(PhysOrg.com) -- The European Space Agency has today released spectacular new observations from the Herschel Space Observatory, including the UK-led SPIRE instrument. Spectrometers on board all three Hershel ...
New climate targets may not change daily life much
16 hours ago |
3.8 / 5 (10) |
3
(AP) -- Americans' day-to-day lives won't change noticeably if President Barack Obama achieves his newly announced goal of slashing carbon dioxide pollution by one-sixth in the next decade, experts say.
Diabetes cases to double and costs to triple by 2034
18 hours ago |
not rated yet |
1
In the next 25 years, the number of Americans living with diabetes will nearly double, increasing from 23.7 million in 2009 to 44.1 million in 2034. Over the same period, spending on diabetes will almost triple, rising from ...
Heavy drinkers exercise to burn off alcohol: British study
Nov 26, 2009 |
not rated yet |
0
More than a quarter of drinkers in England who exercise regularly do so in an attempt to make up for bingeing on alcohol, according to a survey published Thursday.
Plasma produces KO cocktail for MRSA
Nov 26, 2009 |
4.9 / 5 (13) |
2
MRSA (methicillin-resistant Staphylococcus Aureus) and other drug-resistant bacteria could face annihilation as low-temperature plasma prototype devices have been developed to offer safe, quick, easy and un ...
Physicians Explore Link Between Vitamin D Deficiency and Hypertension
Nov 25, 2009 |
5 / 5 (1) |
1
(PhysOrg.com) -- Drs. William White and Pooja Luthra at the University of Connecticut Health Center are investigating a possible link between vitamin D deficiency and high blood pressure.
Cosmic 'Dig' Reveals Vestiges of the Milky Way's Building Blocks
Nov 25, 2009 |
4.6 / 5 (17) |
1
(PhysOrg.com) -- Peering through the thick dust clouds of our galaxy's "bulge" (the myriads of stars surrounding its center), a team of astronomers has unveiled an unusual mix of stars in the stellar grouping ...
Autism treatment: Risky alternative therapies have little basis in science
Nov 24, 2009 |
3 / 5 (2) |
0
James Coman's son has an unusual skill. The 7-year-old, his father says, can swallow six pills at once. Diagnosed with autism as a toddler, the Chicago boy had been placed on an intense regimen of supplements and medications ...
Infrared Image of Circumstellar Disk Illuminates Massive Star Formation Process
Nov 24, 2009 |
4.5 / 5 (4) |
1
(PhysOrg.com) -- A team of astronomers from Ibaraki University, Japan Aerospace Exploration Agency, Kanagawa University, University of Tokyo, Academica Sinica, and National Astronomical Observatory of Japan ...
List of search results for double stars
