3 Piscis Austrini
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Microscopium |
| Right ascension | 21h 13m 17.32730s[1] |
| Declination | −27° 37′ 09.7106″[1] |
| Apparent magnitude (V) | 5.39±0.01[2] |
| Characteristics | |
| Spectral type | K3 III[3] |
| B−V color index | +1.42[4] |
| Astrometry | |
| Radial velocity (Rv) | −46.2±2.4[5] km/s |
| Proper motion (μ) | RA: +98.513 mas/yr[1] Dec.: −110.906 mas/yr[1] |
| Parallax (π) | 8.0734 ± 0.1733 mas[1] |
| Distance | 404 ± 9 ly (124 ± 3 pc) |
| Absolute magnitude (MV) | +0.19[6] |
| Details | |
| Mass | 1.58[7] M☉ |
| Radius | 31.3±1.6[8] R☉ |
| Luminosity | 184+9 −8[1] L☉ |
| Surface gravity (log g) | 1.86[9] cgs |
| Temperature | 4,225±123[10] K |
| Metallicity [Fe/H] | −0.17[9] dex |
| Rotational velocity (v sin i) | <1[11] km/s |
| Age | 2.59+0.83 −1.90[1] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
3 Piscis Austrini, also known as HD 201901 or simply 3 PsA, is an astrometric binary[14] (100% chance[15]) located in the southern constellation Microscopium. It was once part of Piscis Austrinus, the southern fish. The system has a combined apparent magnitude of 5.39,[2] making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of 404 light years[1] and it is currently approaching the Solar System with a heliocentric radial velocity of −46.2 km/s.[5] At its current distance, 3 PsA's brightness is diminished by 0.12 magnitudes due to extinction from interstellar dust[16] and it has an absolute magnitude of +0.19.[6]
The visible component is an evolved red giant with a stellar classification of K3 III.[3] The interferometry-measured angular diameter of the star, after correcting for limb darkening, is 2.03±0.04 mas,[17] which, at its estimated distance, equates to a physical radius of about 20 times the radius of the Sun.[18] However, its actual empirical radius is 31.3 R☉.[8] It has 1.58 times the mass of the Sun[7] and is radiating 184 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,225 K.[10] 3 PsA is metal deficient with an iron abundance 68% that of the Sun ([Fe/H] = −0.17)[9] and it spins too slowly for its projected rotational velocity to be measured accurately.[11] It is estimated to be 2.59 billion years old based on Gaia DR3 models.[1]
References
[edit]- ^ a b c d e f g h i Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361. S2CID 17128864.
- ^ a b Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Volume III: Declinations −40° to −26°. Bibcode:1982mcts.book.....H.
- ^ Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
- ^ a b Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
- ^ a b Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361. S2CID 131780028.
- ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants. Surface brightness relations calibrated by interferometry". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. eISSN 1432-0746. ISSN 0004-6361. S2CID 6077801.
- ^ a b c McWilliam, Andrew (December 1990). "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances". The Astrophysical Journal Supplement Series. 74: 1075. Bibcode:1990ApJS...74.1075M. doi:10.1086/191527. eISSN 1538-4365. ISSN 0067-0049.
- ^ a b Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
- ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars V: Southern stars *". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361. S2CID 54046583.
- ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
- ^ "HD 201901". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-11.
- ^ Eggleton, P. P.; Tokovinin, A. A. (11 September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. eISSN 1365-2966. ISSN 0035-8711. S2CID 14878976.
- ^ Frankowski, A.; Jancart, S.; Jorissen, A. (19 December 2006). "Proper-motion binaries in the Hipparcos catalogue: Comparison with radial velocity data". Astronomy & Astrophysics. 464 (1): 377–392. arXiv:astro-ph/0612449. Bibcode:2007A&A...464..377F. doi:10.1051/0004-6361:20065526. eISSN 1432-0746. ISSN 0004-6361. S2CID 14010423.
- ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711. S2CID 118879856.
- ^ Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005). "CHARM2: An updated Catalog of High Angular Resolution Measurements". Astronomy & Astrophysics. 431 (2): 773–777. Bibcode:2005A&A...431..773R. doi:10.1051/0004-6361:20042039. eISSN 1432-0746. ISSN 0004-6361. S2CID 122267643.
- ^ Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R*) is given by:
