Epsilon Scorpii

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description

ε Scorpii
Template:Location mark
Location of ε Sco (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Scorpius
Right ascension Template:RA[1]
Declination Template:DEC[1]
Apparent magnitude (V) 2.24 - 2.35[2]
Characteristics
Evolutionary stage red clump[3]
Spectral type K1 III[4]
U−B Template:Engvar +1.147[5]
B−V Template:Engvar +1.150[5]
Variable type suspected[2]
Astrometry
Radial velocity (Rv)−2.5[6] km/s
Proper motion (μ) RA: −614.85[1] mas/yr
Dec.: −255.98[1] mas/yr
Parallax (π)51.19±0.22 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)Template:Val[7]
Details
Mass1.31[8] Template:Solar mass
Radius11.6[9] Template:Solar radius
Luminosity60[8] Template:Solar luminosity
Surface gravity (log g)2.34[8] cgs
Temperature4,560[10] K
Metallicity [Fe/H]−0.17[10] dex
Rotational velocity (v sin i)Template:Val[11] km/s
Age3.92[8] Gyr
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
Wei, Larawag, 26 Scorpii, CD−34 11285, FK5 628, GCTP 3823.00, Gl 639.1, GJ 9579, HD 151680, HIP 82396, HR 6241, LHS 3244, SAO 208078[12]
Database references
SIMBADdata

Script error: No such module "Check for unknown parameters".

Epsilon Scorpii (ε Scorpii, abbreviated Eps Sco, ε Sco), formally named Larawag Template:IPAc-en,[13] is a star in the southern zodiac constellation of Scorpius. It has an apparent visual magnitude of +2.3,[5] making it the fifth-brightest member of the constellation. Parallax measurements made during the Hipparcos mission provide an estimated distance to this star of around Template:Convert from the Sun.[1]

Epsilon Scorpii has a stellar classification of K1 III,[4] which indicates it has exhausted the supply of hydrogen at its core and evolved into a giant star. The interferometry-measured angular diameter of this star, after correcting for limb darkening, is Template:Val,[14] which, at its estimated distance, equates to a physical radius of nearly 12 times the radius of the Sun. Presently it is generating energy through the nuclear fusion of helium at its core, which, considering the star's composition, places it along an evolutionary branch termed the red clump.[3] The star's outer atmosphere has an effective temperature of 4,560 K,[10] giving it the orange hue of a cool K-type star.

ε Scorpii is classified as a suspected variable star,[2] although a study of Hipparcos photometry showed a variation of no more than 0.01–0.02 magnitudes.[3] It is an X-ray source with a luminosity of Template:Val.[7][15]

Nomenclature

ε Scorpii (Latinised to Epsilon Scorpii) is the star's Bayer designation.

The star bore the traditional name Larawag in the culture of the Wardaman people of the Northern territory of Australia,[16] meaning clear sighting.[17] In 2016, the IAU organized a Working Group on Star Names (WGSN)[18] to catalog and standardize proper names for stars. The WGSN approved the name Larawag for Epsilon Scorpii on 19 November 2017 and it is now so included in the List of IAU-approved Star Names.[13]

Patrick Moore introduced the name Wei as Chinese name for this star.[19] However, this seems to be a misreading, as Chinese Script error: No such module "Lang". (Script error: No such module "Lang"., English Tail) refers to an asterism (i.e. Chinese constellation) consisting of Epsilon Scorpii, Mu¹ Scorpii, Zeta¹ Scorpii and Zeta² Scorpii, Eta Scorpii, Theta Scorpii, Iota² Scorpii and Iota¹ Scorpii, Kappa Scorpii, Lambda Scorpii and Upsilon Scorpii.[20] Consequently, the name for Epsilon Scorpii itself is Script error: No such module "Lang". (Script error: No such module "Lang".), which means "the Second Star of Tail".[21][22]

In culture

Epsilon Scorpii appears on the flag of Brazil, symbolising the state of Ceará.[23]

References

Template:Reflist

Template:Stars of Scorpius

  1. a b c d e f Cite error: Invalid <ref> tag; no text was provided for refs named aaa474_2_653
  2. a b c Cite error: Invalid <ref> tag; no text was provided for refs named gcvs
  3. a b c Cite error: Invalid <ref> tag; no text was provided for refs named ba10_593
  4. a b Cite error: Invalid <ref> tag; no text was provided for refs named aj132_1_161
  5. a b c Cite error: Invalid <ref> tag; no text was provided for refs named apjs15_459
  6. Cite error: Invalid <ref> tag; no text was provided for refs named scfs
  7. a b Cite error: Invalid <ref> tag; no text was provided for refs named aaa335_591
  8. a b c d Cite error: Invalid <ref> tag; no text was provided for refs named Luck2015
  9. Cite error: Invalid <ref> tag; no text was provided for refs named mcdonald2017
  10. a b c Cite error: Invalid <ref> tag; no text was provided for refs named ajss74_1075
  11. Cite error: Invalid <ref> tag; no text was provided for refs named aj135_3_892
  12. Cite error: Invalid <ref> tag; no text was provided for refs named SIMBAD
  13. a b Script error: No such module "citation/CS1".
  14. Cite error: Invalid <ref> tag; no text was provided for refs named aaa431_773
  15. Cite error: Invalid <ref> tag; no text was provided for refs named aaa352_217
  16. Script error: No such module "citation/CS1".
  17. Script error: No such module "citation/CS1".
  18. Script error: No such module "citation/CS1".
  19. Cite error: Invalid <ref> tag; no text was provided for refs named moore1983
  20. Template:In lang 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, Template:ISBN.
  21. Template:In lang 香港太空館 - 研究資源 - 亮星中英對照表 Template:Webarchive, Hong Kong Space Museum. Accessed on line November 23, 2010.
  22. Ridpath, Ian, Star Tales.
  23. Script error: No such module "citation/CS1".