Menkar

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Star
Menkar (α Ceti)
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation whale
Right ascension 03 h 02 m 16.77 s
declination + 04 ° 05 ′ 23.1 ″
Apparent brightness 2.53 (2.45 to 2.54) mag
Typing
B − V color index +1.64 
U − B color index +1.93 
R − I index +1.16 
Spectral class M1.5 IIIa
Astrometry
Radial velocity -26.08 ± 0.02  km / s
parallax 13.09 ± 0.44  mas
distance 249 ± 8  ly
76 ± 3  pc
Visual absolute brightness M vis -3.2 ± 0.3  mag
Proper movement 
Rec. Share: −10.41 ± 0.51  mas / a
Dec. portion: −76.85 ± 0.36  mas / a
Physical Properties
Dimensions 2.3 ± 0.2  M ☉
radius 89 ± 5  R ☉
Luminosity

1455 ± 328  L ☉

Effective temperature 3,795 ± 70  K
Metallicity [Fe / H] 0.00 ± 0.30
Other names
and catalog entries
Bayer name α Ceti
Flamsteed name 92 Ceti
Bonn survey BD + 03 ° 419
Bright Star Catalog HR 911 [1]
Henry Draper Catalog HD 18884 [2]
Hipparcos catalog HIP 14135 [3]
SAO catalog SAO 110920 [4]
Tycho catalog TYC 58-1618-1 [5]
2MASS catalog 2MASS J03021680 + 0405226 [6]
Other names Menkar, FK5 107

Menkar ( Arabic منخر الحوت, DMG Manḫar al-Ḥūt  , nostril of the whale ') is the name of the star α Ceti (Alpha Ceti ). Menkar is a red giant of the spectral type M1.5IIIa about 250 light years away with about twice the solar mass and almost 90 times the solar radius. The correspondingly large area of ​​Menkar's photosphere ensures, despite its very low surface temperature of around 3800 K, a luminosity that is around 1500 times greater than that of the smaller but hotter sun. Like many red giants , the star is variable , it probably belongs to the slowly irregularly variable stars .

Despite its Bayer designation , it is not the brightest star in the constellation Cetus: Beta Ceti is even brighter with a brightness of 2.04.

The star is also known under the historical proper names Menkab , Mekab , Monkar and Al Minhar . The IAU Working Group on Star Names (WGSN) defined the proper name Menkar as the standardized proper name for this star on June 30, 2016 .

See also

Web links

Individual evidence

  1. ^ A b F. van Leeuwen: Validation of the new Hipparcos reduction . In: Astronomy and Astrophysics . 474, No. 2, November 2007, pp. 653-664. arxiv : 0708.1752 . bibcode : 2007A & A ... 474..653V . doi : 10.1051 / 0004-6361: 20078357 .
  2. ↑ a b T. Tsuji: Cool luminous stars: the hybrid nature of their infrared spectra . In: Astronomy and Astrophysics . 489, No. 3, October 2008, pp. 1271-1289. arxiv : 0807.4387 . bibcode : 2008A & A ... 489.1271T . doi : 10.1051 / 0004-6361: 200809869 .
  3. ↑ alf Cet. In: VSX. AAVSO, accessed October 29, 2018 .
  4. ↑ a b c H. L. Johnson, B. Iriarte, RI Mitchell, WZ Wisniewskj: UBVRIJKL photometry of the bright stars . In: Communications of the Lunar and Planetary Laboratory . 4, No. 99, 1966. bibcode : 1966CoLPL ... 4 ... 99J .
  5. ↑ a b alf Cet. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed October 29, 2018 .
  6. ↑ B. Famaey, A. Jorissen, X. Luri, M. Mayor, S. Udry, H. Dejonghe, C. Turon: Local kinematics of K and M giants from CORAVEL / Hipparcos / Tycho-2 data. Revisiting the concept of superclusters . In: Astronomy and Astrophysics . 430, No. 1, January 2005, pp. 165-186. arxiv : astro-ph / 0409579 . bibcode : 2005A & A ... 430..165F . doi : 10.1051 / 0004-6361: 20041272 .
  7. ↑ a b c d e M. Wittkowski, JP Aufdenberg, T. Driebe, V. Roccatagliata, T. Szeifert, B. Wolff: Tests of stellar model atmospheres by optical interferometry. IV. VINCI interferometry and UVES spectroscopy of Menkar . In: Astronomy and Astrophysics . 460, No. 3, December 2006, pp. 855-864. arxiv : astro-ph / 0610150 . bibcode : 2006A & A ... 460..855W . doi : 10.1051 / 0004-6361: 20066032 .
  8. ↑ Bulletin of the IAU Working Group on Star Names, No. 1, July 2016. (PDF) Retrieved November 9, 2016 (English, 184 KiB).