36 Ophiuchi
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | 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 mas[1] |
| Distance | 19.5 ± 0.1 ly (5.97 ± 0.04 pc) |
| Orbit | |
| Companion | 36 Ophiuchi B |
| Period (P) | 568.9 yr |
| Semi-major 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 | 0.6-1.8×109 [2][3] years |
| Other designations | |
36 Ophiuchi is a triple star system 19.5 light years away from Earth. It is in the 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.
Hunt for substellar objects
The McDonald Observatory team has set limits to the presence of one or more planets[2] around 36 Ophiuchi A with masses between 0.13 and 5.4 Jupiter masses and average separations spanning between 0.05 and 5.2 astronomical units, although the outermost stable orbits around either 36 Ophiuchi A or 36 Ophiuchi B are possible not beyond 1.5 AU.[4]
See also
References
- ^ a b c d e f g h "SIMBAD Astronomical Database". Centre de Données astronomiques de Strasbourg. Retrieved 2007-06-19.
- ^ a b Wittenmeyer et al. (2006).
- ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (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
{{citation}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Irwin et al. (1996).
Further reading
- Irwin, Alan W.; Yang, Stephenson L. S.; Walker, Gordon A. H. (1996), "36 Ophiuchi AB: Incompatibility of the Orbit and Precise Radial Velocities", Publications of the Astronomical Society of the Pacific, 108: 580, doi:10.1086/133768
{{citation}}: Unknown parameter|lastauthoramp=ignored (|name-list-style=suggested) (help) - Cayrel de Strobel, G.; Lebreton, Y.; Perrin, M.-N.; Cayrel, R. (1989), "A thorough spectroscopic study of the very nearby triple system - 36 Ophiuchi", Astronomy and Astrophysics, 225 (2): 369–380
{{citation}}: Unknown parameter|lastauthoramp=ignored (|name-list-style=suggested) (help) - Wittenmeyer, R. A.; Endl, Michael; Cochran, William D.; Hatzes, Artie P.; Walker, G. A. H.; Yang, S. L. S.; Paulson, Diane B. (2006), "Detection Limits from the McDonald Observatory Planet Search Program", Astronomical Journal, 132 (1): 177–188, doi:10.1086/504942
{{citation}}: Unknown parameter|lastauthoramp=ignored (|name-list-style=suggested) (help) - Barnes, Sydney A. (2007), "Ages for Illustrative Field Stars Using Gyrochronology: Viability, Limitations, and Errors", The Astrophysical Journal, 669 (2): 1167–1189, doi:10.1086/519295
{{citation}}: Cite has empty unknown parameter:|lastauthoramp=(help)
External links
- "36 Ophiuchi". SolStation. Retrieved 3 November 2005.
- http://arxiv.org/abs/astro-ph/0604171
