Alpherg

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Star
Alpherg (η Piscium)
AladinLite
Observation
dates equinoxJ2000.0 , epoch : J2000.0
Constellation fishes
Right ascension 01 h 31 m 29.01 s
declination + 15 ° 20 ′ 45 ″
Apparent brightness 3.62 likes
Typing
B − V color index (0.98) 
U − B color index (0.72) 
R − I index (0.50) 
Spectral class G7 IIIa
Astrometry
Radial velocity (13.78 ± 0.07) km / s
parallax (12.03 ± 0.75)  mas
distance (270 ± 20)  ly
(83 ± 5)  pc
Proper movement 
Rec. Share: (25.94 ± 1.17)  mas / a
Dec. portion: (−4.96 ± 1.03)  mas / a
Physical Properties
Dimensions (3.78 ± 0.16)  M
radius (26.48 ± 2.15)  R
Luminosity

(460 ± 80)  L

Effective temperature (4937 ± 40)  K.
Metallicity [Fe / H] (−0.13 ± 0.06)
Age (220 ± 30) mill.  A
Other names
and catalog entries
Bayer name η Piscium
Flamsteed name 99 Piscium
Bonn survey BD + 14 ° 231
Bright Star Catalog HR 437 [1]
Henry Draper Catalog HD 9270 [2]
Hipparcos catalog HIP 7097 [3]
SAO catalog SAO 92484 [4]
2MASS catalog 2MASS J01312901 + 1520452 [5]
Other names FK5 50, Alpherg

Alpherg , Bayer name Eta Piscium (Piscium), Babylonian name Kullat Nunu is a star in the equatorial zone of the starry sky. It has an apparent magnitude of +3.62 mag and belongs to the spectral class G7IIIa. Alpherg is less than 300 light years from Earth and has a diameter that is 26 times larger than that of the Sun. There is evidence of a companion, but little is known about it so far.

Web links

Individual evidence

  1. a b c d e f g h i eta Psc. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed on September 3, 2018 .
  2. a b c d e f J. Maldonado, E. Villaver, C. Eiroa: The metallicity signature of evolved stars with planets . In: Astronomy & Astrophysics . 554, June 2013, p. 18. arxiv : 1303.3418 . A84. bibcode : 2013A & A ... 554A..84M . doi : 10.1051 / 0004-6361 / 201321082 .
  3. Epping J., Straßmaier JN: Astronomical things from Babylon or the knowledge of the Chaldeans about the starry sky. Voices from Maria Laach - Supplement 44. Herder, Freiburg i. Br. 1889. p. 117 ( online )