36 Ophiuchi
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| Observation data Epoch J2000 |
|
|---|---|
| Constellation (pronunciation) |
Ophiuchus |
| Right ascension | A: 17h 15m 20.851s B: 17h 15m 20.978s C: 17h 16m 13.3626s[1] |
| Declination | A: -26° 36′ 09.04″ B: -26° 36′ 10.18″ C: -26° 32′ 46.128″[1] |
| Apparent magnitude (V) | 5.29/5.33/6.34[1] |
| Characteristics | |
| Spectral type | K0 V/K1 V/K5 V[1] |
| U-B color index | 0.51(AB)/1.04 |
| B-V color index | 0.86(AB)/1.15 |
| Variable type | C: RS CV |
| Astrometry | |
| Radial velocity (Rv) | -0.6/0.0/-1.6[1] km/s |
| Proper motion (μ) | RA: -488.2/-473/-479.72[1] mas/yr Dec.: -1156.0/-1143/-1123.37[1] mas/yr |
| Parallax (π) | 167.56 ± 1.06[1] mas |
| Distance | 19.5 ± 0.1 ly (5.97 ± 0.04 pc) |
| Visual binary orbit | |
| Companion | 36 Ophiuchi B |
| Period (P) | 568.9 yr |
| Semimajor axis (a) | 14.7" |
| Eccentricity (e) | 0.922 |
| Inclination (i) | 99.6° |
| Longitude of the node (Ω) | -83.6° |
| Periastron epoch (T) | 1763.39 |
| Details | |
| Mass | 0.85/0.85/0.71 M☉ |
| Radius | 0.81/0.81/0.72 R☉ |
| Luminosity | 0.28/0.27/0.09 L☉ |
| Temperature | 5125/5100/4550 K |
| Metallicity | A: 50-98%Sun B: 120-250%Sun C: 46-100%Sun |
| Rotation | ? |
| Age | ? years |
| Other designations | |
36 Ophiuchi is a triple star system 19.5 light years away from Earth. It is in constellation Ophiuchus.
The primary and secondary stars are nearly identical orange main sequence dwarves of spectral type K0/K1 and the tertiary star is an orange main sequence dwarf of spectral type K5.
Star C is separated from the A-B pair by 700 arc seconds, compared to a minimum of 4.6 arcsec for A-B, so it has a negligible effect on the movements of the A-B pair. Both A and B have active chromospheres.
[edit] See also
[edit] References
- ^ a b c d e f g h SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved on 2007-06-19.
- A.W. Irwin et al, "36 Ophiuchi AB: Incompatibility of the Orbit and Precise Radial Velocities", Publications of the Astronomical Society of the Pacific, July, 1996.
- G. Cayrel de Strobel, Y. Lebreton, M.-N. Perrin, R. Cayrel, "A thorough spectroscopic study of the very nearby triple system - 36 Ophiuchi", Astronomy and Astrophysics, vol. 225, no. 2, Nov. 1989, p. 369-380.
[edit] External links
- 36 Ophiuchi. SolStation. Retrieved on 3 November, 2005.
