85 Pegasi

From Wikipedia, the free encyclopedia
Jump to: navigation, search
85 Pegasi A/B
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pegasus
Right ascension 00h 02m 10.16s[1]
Declination +27° 04′ 56.1″[1]
Apparent magnitude (V) 5.75 / 8.89
Characteristics
Spectral type G5Vb / K7V
Apparent magnitude (B) 6.42 / 11.0
Apparent magnitude (R) 5.38
Apparent magnitude (I) 4.96
Apparent magnitude (J) 4.702
Apparent magnitude (H) 4.179
Apparent magnitude (K) 4.068
U−B color index 0.05 / ?
B−V color index 0.67 / ?
V−R color index 0.37 / ?
R−I color index 0.42 / ?
Variable type None
Astrometry
Radial velocity (Rv) -36.2 km/s
Proper motion (μ) RA: 780.22 ± 2.01[1] mas/yr
Dec.: -917.75 ± 1.20[1] mas/yr
Parallax (π) 82.5 ± 0.8[2] mas
Distance 39.5 ± 0.4 ly
(12.1 ± 0.1 pc)
Absolute magnitude (MV) 5.28 / 8.54
Orbit
Companion 85 Pegasi B
Period (P) 26.28 yr
Semi-major axis (a) 0.83"
Eccentricity (e) 0.38
Inclination (i) 49°
Details
Mass 0.88 / 0.55 M
Radius 0.91 / 0.67 R
Luminosity 0.61 / 0.05 L
Surface gravity (log g) 4.45 / 4.58 cgs
Temperature 5550 / 4200 K
Metallicity 58–75%
Age 3.8–4.4[3] Gyr
Other designations
BDS 12701, HR 9088, HD 224930, LFT 1848, LHS 101, LTT 17088, SAO 91669, HIP 171.

85 Pegasi A

ADS 17175 A, GJ 914 A, BD +26°4734 A, BU 733 A.

85 Pegasi B

ADS 17175 B, GJ 914 B, BD +26°4734 B, BU 733 B.
Database references
SIMBAD data
Exoplanet Archive data
ARICNS data

85 Pegasi is a multiple star system 39.5 light years away[2] in the constellation of Pegasus. The primary component is sixth magnitude 85 Pegasi A, which is a yellow dwarf like our Sun. The secondary component, 85 Pegasi B, is a ninth magnitude orange dwarf that takes 26.28 years to orbit at 10.3 AU around the primary in an elliptical orbit. The orbital distance ranges from 6.4 AU at periastron to 14.2 AU at apastron. 85 Peg BA may have a close, faint red dwarf companion 85 Peg BB within 2 AU from BA. The mass would be 11% solar mass. All components in the star system including Star A are smaller, cooler and less massive, luminous, and metallic than our Sun and 51 Pegasi.

References[edit]

  1. ^ a b c d van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.  Vizier catalog entry
  2. ^ a b Söderhjelm, S. (1999). "Visual binary orbits and masses POST HIPPARCOS". Astronomy and Astrophysics 341: 121–140. Bibcode:1999A&A...341..121S.  Vizier catalog entry
  3. ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal 687 (2): 1264–1293. arXiv:0807.1686. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785. 

External links[edit]