Double Star
Related Category: Astronomy: General
see binary star.
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Double star
This topic is about the astronomical phenomenon. For other uses, see double star (disambiguation).
The Double Star Programme (DSP)
The mission
An illustration of the Double Star spacecraft.
Dusty double stars aftermath of planetary collisions
DR EMILY BALDWIN
ASTRONOMY NOW
Posted: 25 August 2010 ...
Aitken Double Star Catalogue (ADS)
The name by which Robert Aitken's massive New General Catalogue of Double Stars within 120 degrees of the North Pole is generally known.
Double Star is a science fiction novel by Robert A. Heinlein, first serialized in Astounding Science Fiction and published in hardcover the same year....
s, the rotation of Saturn, and the mass of Mars.
Hall was born in Goshen, Connecticut ...
Double Stars
More than half of the stars in the sky are actually members of two-star (binary) systems or multiple-star systems.
Double Stars
A pair of stars close together in the sky. Not all double stars are necessarily in orbit around each other.
Double-Exhaust Model ...
double star
Two stars which are located in the same line of sight from the Earth. They may be binary stars or they may be unrelated and simply lie in the same area of the sky.
Double Star
a grouping of two stars. This grouping can be apparent, where the stars seem close together, or physical, such as a binary system.
Double star. A star made up of two components. They are either genuinely associated (binary stars) or they appear close by chance (optical pair or binary).
E ...
Double Star
(a) A ``system" of two stars that appear - because of coincidental alignment when viewed from Earth - to be close together; it is, however, an optical effect only, ...
The Double Star Library, at the U.S. Naval Observatory
Naming New Extrasolar Planets
Individual specimens
[edit] See also ...
This double star was included by Messier in his catalogue for unknown reasons - he observed it on October 24, 1764. Nebula was listed at this location by Hevelius in 1660. Its components, separated by 49 arcseconds, are magnitude 9.0 and 9.
Double star delta1/delta2 Tel
General:
One of the constellations of the southern hemisphere named by the LaCaille. South of Corona Australis this constellation stretches from RA=18h 10m to RA=20h 30m and DECL=54 degrees to DECL=63 degrees.
Double Stars, Variable Stars, Clusters and Nebulae
Our Sun is a single star with approximately constant brightness. In fact, in the universe, many stars are not alone, they interact with each other to form binary or multiple star systems.
Double stars in Canes Venatici:
Canes Venatici has two attractive binaries: alpha CVn and 25 CVn. Alpha2 and alpha1 CVn form a celebrated fixed double star system. Note that the primary is alpha2, since it is slightly east of its companion.
Double Star designated 61 in Cygnus the Swan
Claim to Fame:
Some of the closest stars to the sun(13th closest). Moving very rapidly through space as seen from Earth at a rate of ~45,000 miles per hour (72,000 km/hr) ...
Double stars: Gamma Arae is a fixed binary with rather faint companion: 3.5, 10; PA 328, separation 18". A second companion is twelfth magnitude: PA 66º, separation 41.6". (Burnham questions whether these form a true binary.) ...
double star (binary star): two stars that lie very close to, and often orbit, each other. Line-of-sight doubles are a consequence of perspective and aren't physically related. Most stars, however, are multiples gravitationally bound together.
DOUBLE STAR
A double star is two stars that appear close to one another in the sky. Some are true binaries (two stars that revolve around one another); others just appear together from the Earth because they are both in the same line-of-sight.
Double stars
A system of two stars that are gravitationally bound to each other. They orbit each other around a common center. They can also be called binary stars.
Dwarf Galaxy ...
A double star may be determined to be optical if its components have sufficiently different proper motions or radial velocities, or if parallax measurements reveal its two components to be at sufficiently different distances from the Earth.
A double star in Ursa Major. [A84]
MKK System
A classification of stellar spectra according to luminosity, devised by Morgan, Keenan and Kellman (see Luminosity Class).
In a double star system in which the two have significantly different masses (by far the most common), the higher mass star will use its internal hydrogen fuel the fastest and become a giant first.
Several double stars were observed during the 17th century, Ursae Majoris being the first on record. In 1784 Christian Mayer published a catalogue of all the double stars then known, which contained 89 pairs. Between 1825 and 1827 F. G. W.
Izar is a double star system. The B component is 2.19 magnitudes dimmer than A and separated from it by 2.867 sec of arc, corresponding to a projected distance of 184 AU (4.7 times the radius of the solar system out to Pluto.) ...
B. Name 10 double stars, clusters, nebulae or galaxies you have seen in binoculars or can point to in the sky.
C. It is 3 a.m. September 30th. Is Orion up?
Washington Double Star Catalog maintained by the United States Naval Observatory is the world's principal database of astrometric double and multiple star information. It provides data on over 98,000 star systems.
Applets, Activities and Software ...
Description: double star
Constellation: Ursa Major
Small Image
Large Image ...
Blazing star, Double star, Multiple star, Shooting star, etc. See under Blazing, Double, etc. -- Nebulous star Astron., a small well-defined circular nebula, having a bright nucleus at its center like a star. -- Star anise Bot.
Observation of double stars gained increasing importance during the 19th century. In 1834, Friedrich Bessel observed changes in the proper motion of the star Sirius, and inferred a hidden companion.
double stars (NASA Thesaurus / NASA SP-7, 1965) Stars which appear as single points of light to the eye but which can be resolved into two point by a telescope.
optical double star Two stars in nearly the same line of sight but differing greatly in distance from the observer, as distinguished from a physical double star. optical haze = terrestrial scintillation.
15 Aquilae is a double star consisting of a yellow 5th-magnitude star and a magnitude 7 companion star.
57 Aquilae is another binary, with two magnitude 6 components and an apparent magnitude of 5.28.
Best example of a double star, with one star shining red the other blue, magnificent.
Author: Alistair Thomson
Related Articles ...
Info: Zeta UMa is a double star that was often used to test the eyes. Sometimes it's called "Horse and Rider".
Eta
Name: Benetnasch (= "wailing women") ...
Double Star - A binary star; two or more stars orbiting each other.
Dust tail - the dust left behind a comet, reflecting sunlight.
Eclipse - When one "body" (like the moon) passes through the shadow of another.
As regards the size of the system, alpha Cen A is a double star with a period of 79.9 yrs. In terms of how the size of the system compares with ours, that is not a well defined question.
Van Biesbroeck (1880-1974) at the Victoria Double Star Conference in 1956 (16th magnitude, red, 1130" distant in 67 degrees and included as Gamma Leporis C in Luyten's LTT catalogue as LTT 2368). Although the published proper motion was given as 0.
Typical uses include viewing the Moon, other objects of the solar system such as Jupiter and Mars, and double stars.
Second in line along the tail is the wide double star Zeta Ursae Majoris. The two members of the double, visible separately with keen eyesight, are called Mizar and Alcor.
Double stars here are treated individually while other lists may combine their brightness
There are statistical variations in measured values
Some stars are actual variables. See the Legend below ...
19(b) compares the results of a pair of observations of a nearby double star called Castor. Spectroscopic observations long ago revealed the double nature of this object, which appears to be a binary-star system.
It is in fact a wide double star. The primary star, α2 Lib has a magnitude 2.7, the secondary, α1 Lib, is 5.2 so only 10% as bright.
A filar micrometer, an instrument normally used in conjunction with a telescope for visual measurement of the separations of double stars, was employed to estimate the diameters of the first four known asteroids.
In 1780, Sir William Herschel discovered that Polaris was a double star with a faint companion star. Polaris is a blue-green Cepheid variable star (its size brightness changes periodically, with period of 3.969778 days; it varyies between mag 1.
Herschel, Sir William 1738-1822 British astronomer who discovered Uranus and cataloged more than 800 double stars and 2,500 nebulae.
Barnard, who used a filar micrometer (an instrument normally employed for visual measurement of the separations of double stars) to estimate the diameters of the first four asteroids.
- The William Herschel Double Star Catalogs Restored - HTML splash page for my Herschel datasets.
- The Complete William Herschel Double Star Catalog - HTML list of all 805 of his confirmed double star discoveries, sorted by right ascension.
Binoculars reveal that it's a double star, with the dimmer one shining above its brighter companion. Zubenelgenubi is thought to be a true binary -- or two stars revolving around a common center of gravity.
Modification of Step One above: the observer would perhaps be better served by using the methodology described by Couteau in Chapter 4 of Observing Visual Double Stars where he explains in detail how to use artificial lighting and small ball ...
Enif(epsilon pegasi) is a double star resolvable in small telescopes. they are a 2.39 magnitude supergiant and a 9 magnitude companion.
Globular cluster M15 is very bright and nice to view in binoculars or small telescopes.
DoDz1 - small, few stars, the three brightest stars, each of which is a double star, form a triangle.
DoDz2 - small, few stars, unclear as to whether the 7th magnitude double star in the same field of view is part of the cluster.
Instruments able to detect such tiny shifts in visible light were developed in the late 1800s and proved especially useful for observing frequency shifts of double stars ("binaries").
a system of two stars that orbit a common center of gravity; also known as a double star
binoculars ...
Sirius The bright jewel of our stellar neighborhood - the "Dog Star'' in the constellation Canis Major - is really a double star, and each member is remarkable among local stars.
In addition to discovering the planet Uranus, he also observed and cataloged over 800 double stars and 2,500 nebulae. He was the first astronomer to correctly describe the spiral structure of our Milky Way Galaxy.
One common way to describe the resolution of a instrument is to state the minimum angular separation at which a double star, whose two components are fairly bright and have very nearly the same brightness, can be distinguished as two separate stars.
Herschel discovered Uranus and cataloged more than 800 double stars and 2,500 nebulae. Huygens, Christiaan 1629-1695 Dutch physicist and astronomer. Huygens first described the nature of Saturn's rings (1655) and discovered its moon Titan.
 See also: Star, Constellation, Sky, Light, Telescope
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