Beta Circini
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Circinus |
Right ascension | 15h 17m 30.8494s[1] |
Declination | −58° 48′ 04.349″[1] |
Apparent magnitude (V) | 4.069[1] |
Characteristics | |
Spectral type | A3 Va[1] |
U−B color index | +0.09[2] |
B−V color index | +0.09[2] |
Astrometry | |
Radial velocity (Rv) | 9.6 ± 2[1] km/s |
Proper motion (μ) | RA: −98.39[1] mas/yr Dec.: −135.46[1] mas/yr |
Parallax (π) | 33.75 ± 0.75[1] mas |
Distance | 97 ± 2 ly (29.6 ± 0.7 pc) |
Absolute magnitude (MV) | +1.64[3] |
Details | |
Radius | 1.3[4] R☉ |
Luminosity | 19[3] L☉ |
Surface gravity (log g) | 4.281[5] cgs |
Temperature | 8,892[5] K |
Metallicity [Fe/H] | 0.16[3] dex |
Rotational velocity (v sin i) | 59[2] km/s |
Age | +212 −116 166[5] Myr |
Other designations | |
Database references | |
SIMBAD | data |
Beta Circini, Latinized from β Circini, is an A-type main sequence star and is the second-brightest star in the constellation of Circinus.[1] It has an apparent visual magnitude of approximately 4.069,[1] which is bright enough to be viewed with the naked eye. Based upon an annual parallax shift of 33.75 mas as seen from the Earth,[1] it is located about 97 light years from the Sun.
With a stellar classification of A3 Va,[1] this is an A-type main-sequence star. It is roughly 166[5] million years old with around 1.3[4] times the Sun's radius. The star is radiating 19[3] times the Sun's luminosity from its photosphere at an effective temperature of 8,892 K.[5] It has one known sub-stellar companion.
Planetary System
Beta Circini b is a distant brown dwarf companion orbiting the host star at a distance of 6,656 AU.[6][7] It has a surface temperature of 2,084.0 K. Its mass was estimated using the Spectrum method which concluded that the object has a mass of ±7.0 MJ. 56.0[6]
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
β Circini b | 56.0 (± 7.0) MJ | 6656.0 | — | — | — | — |
References
- 1 2 3 4 5 6 7 8 9 10 11 12 13 "* bet Cir". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 5, 2008.
- 1 2 3 HR 5670, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 5, 2008.
- 1 2 3 4 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015.
- 1 2 HD 135379, database entry, Catalog of Apparent Diameters and Absolute Radii of Stars (CADARS), 3rd edition, L. E. Pasinetti-Fracassini, L. Pastori, S. Covino, and A. Pozzi, CDS ID II/224. Accessed on line September 5, 2008.
- 1 2 3 4 5 Song, Inseok; et al. (February 2001), "Ages of A-Type Vega-like Stars from uvbyβ Photometry", The Astrophysical Journal, 546 (1): 352–357, arXiv:astro-ph/0010102, Bibcode:2001ApJ...546..352S, doi:10.1086/318269
- 1 2 3 "β Circini b". The Extrasolar Planet Encyclopaedia. Retrieved October 30, 2015.
- ↑ Discovery of a brown dwarf companion to the A3V star β Circini. Retrieved November 9, 2015.