BETA ZEN
Beta Piscis Austrini
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| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Piscis Austrinus |
| Right ascension | 22h 31m 30.33038s[1] |
| Declination | −32° 20′ 45.8653″[1] |
| Apparent magnitude (V) | +4.29[2] |
| Characteristics | |
| Spectral type | A1 V[3] |
| U−B color index | +0.02[2] |
| B−V color index | +0.01[2] |
| Astrometry | |
| Radial velocity (Rv) | 5.5±0.5[4] km/s |
| Proper motion (μ) | RA: +59.12 mas/yr[1] Dec.: −18.83 mas/yr[1] |
| Parallax (π) | 22.84±0.21 mas[1] |
| Distance | 143 ± 1 ly (43.8 ± 0.4 pc) |
| Absolute magnitude (MV) | 1.00[5] |
| Details[6] | |
| Mass | 2.20±0.03 M☉ |
| Radius | 2.20±0.21 (equatorial) 1.75 (polar) R☉ |
| Luminosity | 26.2+1.9 −2.4 L☉ |
| Surface gravity (log g) | 3.78+0.10 −0.13 (equatorial) 4.29±0.05 (polar) cgs |
| Temperature | 8,275+317 −400 (equatorial) 10,300+200 −250 (polar) K |
| Rotational velocity (v sin i) | 26 km/s |
| Age | 141+113 −49 Myr |
| Other designations | |
| β PsA, 17 Piscis Austrini, CD−32°17126, FK5 1592, HD 213398, HIP 111188, HR 8576, SAO 213883, WDS J22315-3221A[7] | |
| Database references | |
| SIMBAD | data |
Beta Piscis Austrini is a star in the southern constellation of Piscis Austrinus that makes part of a binary star system. Its name is a Bayer designation that is Latinized from β Piscis Austrini, and abbreviated Beta PsA or β PsA. It is visible to the naked eye with an apparent visual magnitude of +4.29.[2] Based upon an annual parallax shift of 22.84 mas as seen from the Earth,[1] the star is located 143 light years from the Sun. These coordinates are a source of X-ray emission with a luminosity of 88.5×1020 W, which is most likely coming from an external source.[8]
Characteristics
Beta Piscis Austrini is a white-hued A-type main sequence star with a stellar classification of A1 V.[3] It has an estimated 2.20 times the mass of the Sun and spins with a rather slow projected rotational velocity of 26 km/s. However, the stellar equator is seen nearly pole-on, yielding an equatorial rotational velocity of 314+37
−43 km/s. As a result of its fast rotation, it has an oval shape, with the equatorial circumference being 26%±7% longer than the polar circumference, as well as an equatorial temperature 20%±4% cooler than the polar temperature, due to gravity darkening. The star is radiating 26 times the solar luminosity from its photosphere.[6]
The star is moving through the Galaxy at a speed of 14.4 km/s relative to the Sun. Its projected Galactic orbit carries it between 23,901 and 28,366 light-years from the center of the Galaxy.[9]
There is evidence for an infrared excess, indicating the presence of an orbiting debris disk. This has an estimated temperature of 188 K, indicating an orbital distance of 12 AU from the host star.[10]
Beta Piscis Austrini has a proper motion companion[11] named CD-32°17127, of apparent magnitude 7.04.[12] It is a G-type main-sequence star of spectral class G1V, with 1.04 times the mass of the Sun,[11] 1.03 times the Sun's radius, a luminosity 1.22 times solar and an effective temperature of 6,000 K.[13] This star is separated from β Piscis Austrini by 1,376 astronomical units.[11]
With Delta and Zeta it constituted Tien Kang ("heavenly rope") in China.[14][15]
References
- 1 2 3 4 5 6 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- 1 2 3 4 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series, 34: 1–49, Bibcode:1978A&AS...34....1N.
- 1 2 Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298.
- ↑ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ↑ Gerbaldi, M.; et al. (June 1999), "Search for reference A0 dwarf stars: Masses and luminosities revisited with HIPPARCOS parallaxes", Astronomy and Astrophysics Supplement, 137 (2): 273–292, Bibcode:1999A&AS..137..273G, doi:10.1051/aas:1999248.
- 1 2 Kane, Colin; White, Russel; Jones, Jeremy; Montesinos, Benjamin; Carrazco-Gaxiola, Sebastian; Johns, Tim; Kar, Aman; Jao, Wei-Chun; Henry, Todd (2026-07-02), "The Debris Disk Host β Piscis Austrinus is a Rapidly Rotating Star Seen Nearly Pole-On", arXiv:2607.02487 [astro-ph.SR].
- ↑ "bet PsA -- High proper-motion Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2017-05-27.
- ↑ Schröder, C.; Schmitt, J. H. M. M. (November 2007), "X-ray emission from A-type stars", Astronomy and Astrophysics, 475 (2): 677–684, Bibcode:2007A&A...475..677S, doi:10.1051/0004-6361:20077429.
- ↑ 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, S2CID 119257644.
- ↑ Patel, Rahul I.; et al. (May 2014), "A Sensitive Identification of Warm Debris Disks in the Solar Neighborhood through Precise Calibration of Saturated WISE Photometry", The Astrophysical Journal Supplement Series, 212 (1): 23, arXiv:1403.3435, Bibcode:2014ApJS..212...10P, doi:10.1088/0067-0049/212/1/10, S2CID 119219094, 10.
- 1 2 3 Waisberg, Idel; Klein, Ygal; Katz, Boaz (2023-06-01), "Binarity and beyond in A stars – I. Survey description and first results of VLTI/GRAVITY observations of VAST targets with high Gaia–Hipparcos accelerations", Monthly Notices of the Royal Astronomical Society, 521 (4): 5232–5254, arXiv:2206.05251, Bibcode:2023MNRAS.521.5232W, doi:10.1093/mnras/stad872, ISSN 0035-8711.
- ↑ "CD-32 17127". SIMBAD. Centre de données astronomiques de Strasbourg.
- ↑ Hardegree-Ullman, Kevin K.; Apai, Dániel; Bergsten, Galen J.; Pascucci, Ilaria; López-Morales, Mercedes (2023-06-01), "Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable-zone Exoplanets", The Astronomical Journal, 165 (6): 267, arXiv:2304.12490, Bibcode:2023AJ....165..267H, doi:10.3847/1538-3881/acd1ec, ISSN 0004-6256.
- ↑ Allen, Richard Hinckley (1963), Star Names — Their Lore and Meaning: Piscis Australis, the Southern Fish, retrieved 2017-05-27.
- ↑ Tien Kang was possibly derived from 天綱 (Tiān Gāng) meaning Materials for Making Tents. AEEA opinion is, δ Piscis Austrini marking itself and stand alone in this asterism. See (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 6 日 Archived 2011-05-21 at the Wayback Machine.
External links
- Kaler, James B. (November 12, 2009), "Beta Piscis Austrini", Stars, University of Illinois.
