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Double star

Index Double star

In observational astronomy, a double star or visual double is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. [1]

60 relations: ADS 16402, Alpha Capricorni, Alpha Centauri, Alpha Crucis, Alpha1 Capricorni, Alpha2 Capricorni, Apparent magnitude, Astronomical spectroscopy, Astronomy, Bayer designation, Benedetto Castelli, Binary star, Binary stars in fiction, Capella, Castor (star), Crux, D. Reidel, Double Star (disambiguation), Earth, Edward Charles Pickering, Eta1 Coronae Australis, Eta2 Coronae Australis, Friedrich Georg Wilhelm von Struve, Galileo Galilei, Gamma Arietis, Gravity, James Dunlop, Joseph von Fraunhofer, Kappa1 Coronae Australis, Kappa2 Coronae Australis, Magnitude (astronomy), Nicolas-Louis de Lacaille, Occultation, Orbit, Otto Struve, P Eridani, Polaris, Position angle, Procyon, Proper motion, Proxima Centauri, Radial velocity, Robert Grant Aitken, Robert Hooke, Sherburne Wesley Burnham, Sirius, Star, Star system, Sydney Observatory, Telescope, ..., Theta Muscae, United States Naval Observatory, Ursa Major, Washington Double Star Catalog, William Herschel, Winnecke 4, Xi Centauri, Xi Sagittarii, Zeta Ursae Majoris, 44 Boötis. Expand index (10 more) »

ADS 16402

ADS 16402 is a binary star system, composed of two sun-like stars located approximately 525 light-years away in the constellation Lacerta.

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Alpha Capricorni

Alpha Capricorni (α Capricorni, abbreviated Alpha Cap, α Cap) is an optical double star in the constellation of Capricornus.

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Alpha Centauri

Alpha Centauri (α Centauri, abbreviated Alf Cen or α Cen) is the star system closest to the Solar System, being from the Sun.

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Alpha Crucis

Alpha Crucis (α Crucis, abbreviated Alpha Cru, α Cru) is a multiple star system located 321 light-years from the Sun in the constellation of Crux and part of the asterism known as the Southern Cross.

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Alpha1 Capricorni

Alpha1 Capricorni, Latinized from α1 Capricorni, is a double star in the southern constellation of Capricornus.

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Alpha2 Capricorni

Alpha2 Capricorni (α2 Capricorni), or Algedi, is a triple star system in the southern constellation of Capricornus.

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Apparent magnitude

The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.

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Astronomical spectroscopy

Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light and radio, which radiates from stars and other celestial objects.

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Astronomy (from ἀστρονομία) is a natural science that studies celestial objects and phenomena.

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Bayer designation

A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name.

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Benedetto Castelli

Benedetto Castelli (1578 – 9 April 1643), born Antonio Castelli, was an Italian mathematician.

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Binary star

A binary star is a star system consisting of two stars orbiting around their common barycenter.

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Binary stars in fiction

A significant number of science fiction works have explored the imaginative possibilities of binary or multiple star systems.

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Capella, also designated Alpha Aurigae (α Aurigae, abbreviated Alpha Aur, α Aur), is the brightest star in the constellation of Auriga, the sixth-brightest in the night sky, and the third-brightest in the northern celestial hemisphere after Arcturus and Vega.

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Castor (star)

Castor, also designated Alpha Geminorum (α Geminorum, abbreviated Alpha Gem, α Gem) is the second-brightest star in the constellation of Gemini and one of the brightest stars in the night sky.

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Crux is a constellation located in the southern sky in a bright portion of the Milky Way.

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D. Reidel


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Double Star (disambiguation)

Double Star is a novel by Robert Heinlein.

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Earth is the third planet from the Sun and the only astronomical object known to harbor life.

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Edward Charles Pickering

Prof Edward Charles Pickering FRS(For) HFRSE (July 19, 1846 – February 3, 1919) was an American astronomer and physicist and the older brother to William Henry Pickering.

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Eta1 Coronae Australis

Eta1 Coronae Australis (η1 CrA) is a star located in the constellation Corona Australis.

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Eta2 Coronae Australis

Eta2 Coronae Australis (η2 CrA), is a star located in the constellation Corona Australis.

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Friedrich Georg Wilhelm von Struve

Friedrich Georg Wilhelm von Struve (Василий Яковлевич Струве, trans. Vasily Yakovlevich Struve; 15 April 1793 –) was a German-Russian astronomer and geodesist from the famous Struve family.

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Galileo Galilei

Galileo Galilei (15 February 1564Drake (1978, p. 1). The date of Galileo's birth is given according to the Julian calendar, which was then in force throughout Christendom. In 1582 it was replaced in Italy and several other Catholic countries with the Gregorian calendar. Unless otherwise indicated, dates in this article are given according to the Gregorian calendar. – 8 January 1642) was an Italian polymath.

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Gamma Arietis

Gamma Arietis (γ Arietis, abbreviated Gamma Ari, γ Ari) is a binary star in the northern constellation of Aries.

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Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward (or gravitate toward) one another.

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James Dunlop

James Dunlop FRSE (31 October 1793 – 22 September 1848) was a Scottish astronomer, noted for his work in Australia.

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Joseph von Fraunhofer

Joseph Ritter von Fraunhofer (6 March 1787 – 7 June 1826) was a Bavarian physicist and optical lens manufacturer.

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Kappa1 Coronae Australis

Kappa1 Coronae Australis (κ1 CrA), is a star located in the constellation Corona Australis.

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Kappa2 Coronae Australis

Kappa2 Coronae Australis (K2 CrA), is a star located in the constellation Corona Australis.

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Magnitude (astronomy)

In astronomy, magnitude is a logarithmic measure of the brightness of an object in a defined passband, often in the visible or infrared spectrum, but sometimes across all wavelengths.

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Nicolas-Louis de Lacaille

Abbé Nicolas-Louis de Lacaille, formerly sometimes spelled de la Caille, (15 March 1713 – 21 March 1762) was a French astronomer.

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An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer.

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In physics, an orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star or a natural satellite around a planet.

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Otto Struve

Otto Struve (August 12, 1897 – April 6, 1963) was a Russian-American astronomer.

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P Eridani

p Eridani (6 Eri, DUN 5) is a binary star system in the constellation of Eridanus (the River) whose distance is approximately 26 light-years.

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Polaris, designated Alpha Ursae Minoris (Ursae Minoris, abbreviated Alpha UMi, UMi), commonly the North Star or Pole Star, is the brightest star in the constellation of Ursa Minor.

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Position angle

Position angle, usually abbreviated PA, is the convention for measuring angles on the sky in astronomy.

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Procyon, also designated Alpha Canis Minoris (α Canis Minoris, abbreviated Alpha CMi, α CMi), is the brightest star in the constellation of Canis Minor.

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Proper motion

Proper motion is the astronomical measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more distant stars.

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Proxima Centauri

Proxima Centauri, or Alpha Centauri C, is a red dwarf, a small low-mass star, about from the Sun in the constellation of Centaurus.

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Radial velocity

The radial velocity of an object with respect to a given point is the rate of change of the distance between the object and the point.

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Robert Grant Aitken

Robert Grant Aitken (December 31, 1864 – October 29, 1951) was an American astronomer.

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Robert Hooke

Robert Hooke FRS (– 3 March 1703) was an English natural philosopher, architect and polymath.

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Sherburne Wesley Burnham

Sherburne Wesley Burnham (December 12, 1838 – March 11, 1921) was an American astronomer.

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Sirius (a romanization of Greek Σείριος, Seirios,."glowing" or "scorching") is a star system and the brightest star in the Earth's night sky.

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A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.

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Star system

A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction.

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Sydney Observatory

Sydney Observatory is located on a hill now known as Observatory Hill in the centre of Sydney.

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A telescope is an optical instrument that aids in the observation of remote objects by collecting electromagnetic radiation (such as visible light).

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Theta Muscae

Theta Muscae (θ Muscae) is a multiple star system in the southern constellation Musca ("the Fly") with an apparent magnitude of 5.5.

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United States Naval Observatory

The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States, with a primary mission to produce Positioning, Navigation and Timing (PNT) for the United States Navy and the United States Department of Defense.

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Ursa Major

Ursa Major (also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory.

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Washington Double Star Catalog

The Washington Double Star Catalog, or WDS, is a catalog of double stars, maintained at the United States Naval Observatory.

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William Herschel

Frederick William Herschel, (Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer, composer and brother of fellow astronomer Caroline Herschel, with whom he worked.

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Winnecke 4

Winnecke 4 (also known as Messier 40 or WNC 4) is a double star in the constellation Ursa Major.

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Xi Centauri

The Bayer designation Xi Centauri (ξ Cen / ξ Centauri) is shared by two star systems, in the constellation Centaurus.

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Xi Sagittarii

The Bayer designation Xi Sagittarii (ξ Sagittarii) is shared by two stars, ξ1 Sagittarii and ξ² Sagittarii, in the constellation Sagittarius, separated by 0.46° in the sky.

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Zeta Ursae Majoris

Mizar is a 2nd magnitude star in the handle of the Big Dipper asterism in the constellation of Ursa Major.

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44 Boötis

44 Boötis or i Boötis is a triple star system in the constellation Boötes.

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Double star designation, Double star designations, Double stars, Double stars (astronomy), Double-star, Optical binary, Optical companion, Optical double, Optical double star, Visual companion, Visual companions.


[1] https://en.wikipedia.org/wiki/Double_star

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