Mirfak

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Star
Mirfak (α Persei)
FindMirfak.png
Finding Mirfak in the sky
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Perseus
Right ascension 03 h 24 m 19.37 s
declination + 49 ° 51 ′ 40.3 ″
Apparent brightness 1.79 likes
Typing
B − V color index +0.48 
U − B color index +0.37 
R − I index +0.33 
Spectral class F5 Ib
Astrometry
Radial velocity (−2.0 ± 0.1) km / s
parallax (6.44 ± 0.17)  mas
distance (506 ± 13)  ly
(155.3 ± 4.1)  pc  
Visual absolute brightness M vis approx. −4.2 mag
Proper movement 
Rec. Share: (+23.75 ± 0.16)  mas / a
Dec. portion: (−26.23 ± 0.15)  mas / a
Physical Properties
Dimensions 11  M ☉
radius 56  R ☉
Effective temperature 6600  K
Other names
and catalog entries
Bayer name α Persei
Flamsteed name 33 Persei
Bonn survey BD + 49 ° 917
Bright Star Catalog HR 1017 [1]
Henry Draper Catalog HD 20902 [2]
Hipparcos catalog HIP 15863 [3]
SAO catalog SAO 38787 [4]
Tycho catalog TYC 3320-2808-1 [5]Template: Infobox star / maintenance / specification of the TYC catalog
Other names FK5  120
annotation
  1. ↑ Roughly estimated from apparent brightness and distance.

Mirfak ( α Persei , Alpha Persei ) lies in the center of the constellation Perseus and is its brightest star. Its apparent magnitude is around 1.8, making it one of the 50 brightest stars in the night sky . Mirfak is a yellow supergiant ; its mass is around eleven times that of the sun, its diameter around 56 times that of the sun.

You can easily find Alpha Persei in the sky if you extend the second line of the letter W , which is formed by the constellation Cassiopeia , about five times beyond the star Delta Cassiopeiae - it forms the first angle of the W. Mirfak is part of the five star series . In addition to Mirfak , another proper name is Algenib , which can lead to confusion with the star of the same name in the constellation Pegasus . Both names are of Arabic origin. Mirfak , also written Mirphak , comes from the Arabicالمرفق الثريا / al-mirfaq aṯ-ṯurayyā  / 'Elbow of the Pleiades '. Algenib , also Algeneb , Elgenab , Gęnib , Chenib or Alchemb , is derived fromالجنب / al-ǧanb orالجانب / al-ǧānib  / 'the flank'.

The IAU Working Group on Star Names (WGSN) established the proper name Mirfak as the standardized proper name for this star on July 20, 2016 .

Web links

Individual evidence

  1. ↑ a b c Hipparcos catalog (ESA 1997)
  2. ↑ a b c Bright Star Catalog
  3. ↑ Pulkovo radial velocities for 35493 HIP stars
  4. ↑ a b c Hipparcos, the New Reduction (van Leeuwen, 2007)
  5. ↑ Bulletin of the IAU Working Group on Star Names, No. 1, July 2016. (PDF) Retrieved November 9, 2016 (English, 184 KiB).