| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 03 46 08.53581 |
| Declination | −12° 06′ 05.7282″ |
| Apparent magnitude (V) | 4.40 (4.38 - 4.44) |
| Characteristics | |
| Evolutionary stage | asymptotic giant branch |
| Spectral type | M1 III |
| U−B color index | +1.96 |
| B−V color index | +1.61 |
| Variable type | Lb? |
| Astrometry | |
| Radial velocity (Rv) | 45.2±0.1 km/s |
| Proper motion (μ) | RA: +55.98 mas/yr Dec.: +59.28 mas/yr |
| Parallax (π) | 6.78 ± 0.53 mas |
| Distance | 480 ± 40 ly (150 ± 10 pc) |
| Absolute magnitude (MV) | −1.40 |
| Details | |
| Radius | 77 R☉ |
| Luminosity | 1,123 L☉ |
| Temperature | 3,841 K |
| Other designations | |
| π Eridani, π Eri, 26 Eridani, BD-12° 707, HD 23614, HIP 17593, HR 1162, SAO 149158. | |
| Database references | |
| SIMBAD | data |
Pi Eridani, Latinized from π Eridani, is a star in the constellation Eridanus. It has an apparent visual magnitude of 4.40, which is bright enough to be seen on a dark, clear night. Based upon parallax measurements, it is located roughly 480 light years from the Sun.
This is an evolved red giant star with a stellar classification of M1 III, and is currently on the asymptotic giant branch. It is a slow irregular variable type LB that can increase in magnitude up to 4.38. The measured angular diameter of this star is 4.8±0.5 mas. At the estimated distance of Pi Eridani, this yields a physical size of about 77 times the radius of the Sun. It shines with 1,123 times the luminosity of the Sun from an outer atmosphere at an effective temperature of 3,841 K.
References
- ^ 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.
- ^ Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
- ^ Samus, N. N.; Durlevich, O. V.; et al. (2007), Combined General Catalogue of Variable Stars (GCVS4.2), retrieved 2016-09-30. VizieR On-line Data Catalog: B/gcvs.
{{citation}}: External link in|postscript= - ^ Eggen, O. J. (1992), "Asymptotic giant branch stars near the sun", The Astronomical Journal, 104: 275, Bibcode:1992AJ....104..275E, doi:10.1086/116239.
- ^ Houk, N.; Smith-Moore, M. (1988), Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars, vol. 4, Bibcode:1988mcts.book.....H.
- 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, S2CID 119231169.
- 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.
- ^ Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3 ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R*) is given by:
- ^ McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- "* pi. Eri". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-11.
{{cite web}}: CS1 maint: postscript (link) - Mennessier, M. O.; et al. (August 2001), "Long period variable stars: galactic populations and infrared luminosity calibrations", Astronomy and Astrophysics, 374 (3): 968–979, arXiv:astro-ph/0105552, Bibcode:2001A&A...374..968M, doi:10.1051/0004-6361:20010764, S2CID 15721872.
- Richichi, A.; Percheron, I. (May 2005), "First results from the ESO VLTI calibrators program", Astronomy and Astrophysics, 434 (3): 1201–1209, arXiv:astro-ph/0501532, Bibcode:2005A&A...434.1201R, doi:10.1051/0004-6361:20042257, S2CID 2847613.
