Barnard's star


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Related to Barnard's star: Proxima Centauri

Barnard's star,

star with the largest observed proper motionproper motion,
in astronomy, apparent movement of a star on the celestial sphere, usually measured as seconds of arc per year; it is due both to the actual relative motions of the sun and the star through space. Proper motion reflects only transverse motion, i.e.
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 (rate of motion across the sky with respect to other stars); located in the constellation Ophiuchus. The star's large proper motion, 10.28" per year (or half the moon's apparent diameter in a century), is due in part to the fact that it is the second-nearest star, being at a distance of 5.98 light-years. Barnard's star was discovered in 1916 by E. E. Barnard, an observer known also for his discoveries of 16 comets. It is a faint red dwarf star, apparent magnitudemagnitude,
in astronomy, measure of the brightness of a star or other celestial object. The stars cataloged by Ptolemy (2d cent. A.D.), all visible with the unaided eye, were ranked on a brightness scale such that the brightest stars were of 1st magnitude and the dimmest stars
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 9.5, of spectral classspectral class,
in astronomy, a classification of the stars by their spectrum and luminosity. In 1885, E. C. Pickering began the first extensive attempt to classify the stars spectroscopically.
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 M5, lying near the bottom of the main sequence in the Hertzsprung-Russell diagramHertzsprung-Russell diagram
[for Ejnar Hertzsprung and H. N. Russell], graph showing the luminosity of a star as a function of its surface temperature. The luminosity, or absolute magnitude, increases upwards on the vertical axis; the temperature (or some temperature-dependent
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. Slight oscillations in its motion indicate that it has at least one unseen companion.

Barnard's star

A red dwarf star in the constellation Ophiuchus that was discovered in 1916 by E.E. Barnard. The fourth-nearest star to the Sun, after the Alpha Centauri system, it has the largest known proper motion (10″.3 per year) and thus moves a distance equivalent to the Moon's diameter in 180 years. Observations of the star's position over many years show slight oscillating variations in right ascension and declination. It is thought that this wobbling motion is due to the presence of one or more planets orbiting the star. mv : 9.53; Mv : 13.21; spectral type: M4 V; distance: 1.83 pc.

Barnard's star

[′bär·nərdz ¦stär]
(astronomy)
A star 6.1 light-years away from earth, of visual magnitude 9.5 and proper motion of 10.31 seconds of arc annually.
References in periodicals archive ?
0) DOLIDZE 27 Open Cluster 16h36m5 -08 [degrees]56' NGC 6218-M12 Globular Cluster 16 47 2 -01 58 NGC 6240 Galaxy 16 53 0 +02 24 NGC 6254-M10 Globular Cluster 16 57 1 -04 06 NGC 6273-M19 Globular Cluster 17 02 6 -26 16 ESO 587-SC04 Open Cluster 17 04 4 -19 27 NGC 6284 Globular Cluster 17 04 5 -24 47 B 57 Dark Nebula 17 08 3 -22 50 NGC 6309 Planetary Nebula 17 14 1 -12 55 NGC 6333-M9 Globular Cluster 17 19 2 -18 31 B 78 Dark Nebula 17 21 1 -26 47 B 72 Dark Nebula 17 23 5 -23 38 BARNARD'S STAR Star 17 57 8 +04 44 Object Mag.
By comparison, Barnard's star resides 6 light-years away, and our nearest neighbor, at a distance of 4 light years, is the system of three stars collectively known as Alpha Centauri.
No one realized this until amateur astronomer and paper coauthor Kevin Apps alerted Muirhead and his team to the idea that KOI-961 bore a remarkable resemblance to another red dwarf called Barnard's Star, a nearby star that's one of the most well-studied.
The characteristics of Barnard's Star allowed the team to infer the properties of KOI-961, which is needed to deduce the nature of the planetary system from the star's light curve, a plot of how the star dims over time due to transiting planets.
Barnard's star is a particularly famous example of a star with such a wobble, and certain astronomers have followed its motions for decades.