"Eltanin" and "Etamin" redirect here. For other uses, see Eltanin (disambiguation) and Etamin (disambiguation).
Gamma Draconis
Location of γ Draconis (circled)
Observation data Epoch J2000 Equinox J2000
Constellation
Draco
Right ascension
17h 56m 36.36988s[1]
Declination
+51° 29′ 20.0242″[1]
Apparent magnitude (V)
2.23[2]
Characteristics
Spectral type
K5 III[3]
U−B color index
+1.87[2]
B−V color index
+1.53[2]
Astrometry
Radial velocity (Rv)
–28.19 ± 0.36[4] km/s
Proper motion (μ)
RA: –8.48[1] mas/yr Dec.: –22.79[1] mas/yr
Parallax (π)
21.14 ± 0.10 mas[1]
Distance
154.3 ± 0.7 ly (47.3 ± 0.2 pc)
Absolute magnitude (MV)
−1.93 ± 0.07[5]
Details
Mass
1.72[6]M☉
Radius
48.15 ± 1.09[5]R☉
Luminosity
471 ± 30[5]L☉
Surface gravity (log g)
1.55[5] cgs
Temperature
3,930[5] K
Metallicity [Fe/H]
–0.14[7] dex
Rotational velocity (v sin i)
6.0[4] km/s
Other designations
Eltanin, 33 Draconis, BD +51°2282, FK5 676, HD 164058, HIP 87833, HR 6705, SAO 30653
Database references
SIMBAD
data
Gamma Draconis (γ Draconis, abbreviated Gamma Dra, γ Dra), formally named Eltanin/ɛlˈteɪnɪn/,[8][9] is a star in the northern constellation of Draco. Contrary to its gamma-designation (historically third-ranked), it is the brightest object in Draco at magnitude 2.2,[1] outshining Beta Draconis by nearly half a magnitude and Alpha Draconis by over a magnitude.
Gamma Draconis is at a distance of 154.3 light-years (47.3 parsecs) from the Sun,[1] as determined by parallax measurements from the Hipparcos astrometry satellite.[10][11] In 1728, while unsuccessfully attempting to measure the parallax of this star, the English astronomer James Bradley discovered the aberration of light resulting from the relative movement of the Earth. Bradley's discovery apparently confirmed Copernicus' theory that the Earth revolved around the Sun.[12] It is drifting closer to the Solar System with a radial velocity of about –28 km/s.
In 1.5 million years, Gamma Draconis will pass within 28 light-years of Earth. For a period, if its current absolute magnitude does not change, it will be the brightest star in the night sky, nearly as bright as Sirius is at present.[12][13] It is by far the brightest star having a zenith above a point near London which led to its vaunting in these places as the "zenith star".[14] Nearby this red star to the south-southeast is Vega, a bright, well-known star in Lyra.
^ abcdefgCite error: The named reference LEEUWEN was invoked but never defined (see the help page).
^ abcOja, T. (August 1991). "UBV photometry of stars whose positions are accurately known. VI". Astronomy and Astrophysics Supplement Series. 89 (2): 415–419. Bibcode:1991A&AS...89..415O.
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^Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub. ISBN 978-1-931559-44-7.
^"IAU Catalog of Star Names". Retrieved 28 July 2016.
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^ abCite error: The named reference KALER was invoked but never defined (see the help page).
^Tomkin, Jocelyn (April 1998). "Once and Future Celestial Kings". Sky and Telescope. 95 (4): 59–63. Bibcode:1998S&T....95d..59T. – based on computations from HIPPARCOS data. (The calculations exclude stars whose distance or proper motion is uncertain.) PDF[permanent dead link]
^Cite error: The named reference allen1963 was invoked but never defined (see the help page).
GammaDraconis (γ Draconis, abbreviated Gamma Dra, γ Dra), formally named Eltanin /ɛlˈteɪnɪn/, is a star in the northern constellation of Draco. Contrary...
constellation, GammaDraconis (Eltanin), which Bayer placed in his tertiae magnitude class although its current apparent magnitude is 2.24. α Draconis (Latinised...
Beta Draconis, a name Latinized from β Draconis, is a binary star system and the third-brightest star in the northern circumpolar constellation of Draco...
Mu Draconis (μ Draconis, abbreviated Mu Dra, μ Dra) is a multiple star system near the head of the constellation of Draco. With a combined magnitude of...
City of Illusions is a 1967 science fiction novel by American writer Ursula K. Le Guin. It is set on Earth in the distant future, and is part of her Hainish...
engagements against the NTF are about to commence, an incident in the GammaDraconis system leads to the 3rd Fleet of the GTVA being reassigned to the star...
Angeles Media Fund. The story is set on Werel, the third planet of the GammaDraconis system. The planet has an orbital period of 60 Earth years, and is approaching...
"the Four" الربع, العوائذ الْرُّبَع, الْعَوَائِذ GammaDraconis, Xi Draconis, Nu Draconis, Beta Draconis al-ʽAwwād the Lutanist / Lute Player العواد الْعَوَّاد...
Iota Draconis (ι Draconis, abbreviated Iota Dra, ι Dra), also named Edasich /ˈɛdəsɪk/, is a star in the northern circumpolar constellation of Draco. A...
as a ring of mother camels – Beta Draconis (Rastaban), GammaDraconis (Eltanin), Nu Draconis (Kuma) and Xi Draconis (Grumium) – surrounding a foal (the...
2.14 Lambda Velorum Star 2.23 Gamma Cygni Star Suspected variable star 2.23 Alpha Cassiopeiae Star 2.230 GammaDraconis Star 2.24 2.21 Alpha Coronae Borealis...
Xi Draconis (ξ Draconis, abbreviated Xi Dra, ξ Dra) is a double or binary star in the northern circumpolar constellation of Draco. It has an apparent visual...
distance from Earth to a star other than the Sun. Hooke selected the star GammaDraconis and chose the method of parallax determination. In 1669, after several...
1979. The pieces are all named after stars Alpha Centauri Beta Cygni GammaDraconis Delta Orionis The cycle was premiered by Gilbert Kalish and Paul Jacobs...
for his work with Bradley in attempting to measure the parallax of GammaDraconis leading to the discovery of the aberration of light. Molyneux was interested...
observatory to begin their observations of stellar parallax of the star GammaDraconis. The observations, which start on December 3, lead to Bradley's pioneering...
Molyneux until Molyneux's death in 1728, trying to measure the parallax of GammaDraconis. This stellar parallax ought to have shown up, if it existed at all...
Eta Draconis (η Draconis, abbreviated Eta Dra, η Dra) is a binary star in the northern circumpolar constellation of Draco. Despite having an apparent visual...
1728 best known for his work in attempting to measure the parallax of GammaDraconis leading to the discovery of the aberration of light Geminiano Montanari...
Zeta Draconis (ζ Draconis, abbreviated Zet Dra, ζ Dra) is a binary star in the northern circumpolar constellation of Draco. With an apparent visual magnitude...
Pictoris is the south pole star of Mercury while Omicron Draconis is its north star. 42 Draconis is the closest star to the north pole of Venus. Eta1 Doradus...
postulates. 1674 – Robert Hooke makes his observations of the GammaDraconis star, or γ Draconis for short. He proves a variation in its position on the sky...
observatory to begin their observations of stellar parallax of the star GammaDraconis. The observations, which start on December 3, lead to Bradley's pioneering...
CX Draconis is an interacting binary star system in the northern constellation of Draco, abbreviated CX Dra. It has the designation HD 174237 in the Henry...
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