Astronomy:Beta Circini
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Circinus |
| Right ascension | 15h 17m 30.8488s[1] |
| Declination | −58° 48′ 04.3384″[1] |
| Apparent magnitude (V) | 4.069[2] |
| Characteristics | |
| Spectral type | A3 Va[2] |
| U−B color index | +0.09[3] |
| B−V color index | +0.09[3] |
| Astrometry | |
| Radial velocity (Rv) | 9.6 ± 2[2] km/s |
| Proper motion (μ) | RA: −96.742±0.491[1] mas/yr Dec.: −136.541±0.621[1] mas/yr |
| Parallax (π) | 35.1736 ± 0.4253[1] mas |
| Distance | 93 ± 1 ly (28.4 ± 0.3 pc) |
| Absolute magnitude (MV) | +1.64[4] |
| Details | |
| Radius | 1.3[5] R☉ |
| Luminosity | 19[4] L☉ |
| Surface gravity (log g) | 4.281[6] cgs |
| Temperature | 8676±33[7] K |
| Metallicity [Fe/H] | 0.16[4] dex |
| Rotational velocity (v sin i) | 59[3] km/s |
| Age | 370–500[7] 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.[2] It has an apparent visual magnitude of approximately 4.069,[2] which is bright enough to be viewed with the naked eye. Based upon an annual parallax shift of 35.17 mas as seen from the Earth,[2] it is located about 93 light years from the Sun.
With a stellar classification of A3 Va,[2] this is an A-type main-sequence star. It is between 370 and 500 million years old[7] with around 1.3[5] times the Sun's radius. The star is radiating 19[4] times the Sun's luminosity from its photosphere at an effective temperature of 8,676 K.[7] 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.[8][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 56.0±7.0 MJ.[8]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | 56.0 (± 7.0) MJ | 6656.0 | — | — | — | — |
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 "* bet Cir". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+bet+Cir.
- ↑ 3.0 3.1 3.2 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.
- ↑ 4.0 4.1 4.2 4.3 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 5.0 5.1 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.
- ↑
- ↑ 7.0 7.1 7.2 7.3 7.4 Smith, L. C. et al. (2015). "Discovery of a brown dwarf companion to the A3V star β Circini". Monthly Notices of the Royal Astronomical Society 454 (4): 4476–4483. doi:10.1093/mnras/stv2290. Bibcode: 2015MNRAS.454.4476S. https://academic.oup.com/mnras/article/454/4/4476/1003701.
- ↑ 8.0 8.1 8.2 "β Circini b". Extrasolar Planets Encyclopaedia. https://exoplanet.eu/catalog/beta_cir_b--2461/. Retrieved October 30, 2015.
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