85 Pegasi
From Wikipedia, the free encyclopedia
| 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) | 82.17 ± 2.23[1] mas |
| Distance | 40 ± 1 ly (12.2 ± 0.3 pc) |
| Absolute magnitude (MV) | 5.28 / 8.54 |
| Orbit | |
| Companion | 85 Pegasi B |
| Period (P) | 26.28 yr |
| Semimajor 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 |
| Temperature | 5550 / 4200 K |
| Metallicity | 58–75% |
| Age | 3.8–4.4[2] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
85 Pegasi is a multiple star system 40.5 light years away 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.
As of 2010, no known extrasolar planets have been detected around 85 Pegasi, but 51 Pegasi has a hot Jupiter planet, which was the first exoplanet discovered to be orbiting around an ordinary star.
[edit] References
- ^ a b c d e van Leeuwen, F. (2007). "HIP 171". Hipparcos, the New Reduction. http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=I/311/hip2&recno=171. Retrieved 2010-12-20.
- ^ 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. Bibcode 2008ApJ...687.1264M. doi:10.1086/591785.
- J. Fernandes, P. Morel, Y. Lebreton (2002). "A calibration of the 85 Peg binary system". Astronomy and Astrophysics 392 (2): 529–533. Bibcode 2002A&A...392..529F. doi:10.1051/0004-6361:20020962. http://www.aanda.org/index.php?option=article&access=standard&Itemid=129&url=/articles/aa/full/2002/35/aa1948/aa1948.html. Retrieved 2007-06-06.
[edit] External links
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
||||||||||||||
 |
This binary or multiple star system–related article is a stub. You can help Wikipedia by expanding it. |
