Epsilon Leporis
  | |
| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Lepus |
| Right ascension | 05h 05m 27.66537s[1] |
| Declination | −22° 22′ 15.7239″[1] |
| Apparent magnitude (V) | +3.166[2] |
| Characteristics | |
| Spectral type | K4 III[3] |
| U−B color index | +1.783[2] |
| B−V color index | +1.478[2] |
| Astrometry | |
| Radial velocity (Rv) | +1.0[4] km/s |
| Proper motion (μ) | RA: +21.13[1] mas/yr Dec.: −73.11[1] mas/yr |
| Parallax (π) | 15.5999±0.1074 mas[5] |
| Distance | 209 ± 1 ly (64.1 ± 0.4 pc) |
| Absolute magnitude (MV) | −1.02±0.10[6] |
| Details[6] | |
| Mass | 1.70±0.19 M☉ |
| Radius | 40.1±3.2 R☉ |
| Luminosity | 372[7] L☉ |
| Surface gravity (log g) | 1.43±0.09 cgs |
| Temperature | 4,131 K |
| Metallicity [Fe/H] | −0.02 dex |
| Age | 1.72±0.47 Gyr |
| Other designations | |
| Ping, ε Lep, 2 Leporis, NSV 1826, BD−22°1000, FK5 186, HD 32887, HIP 23685, HR 1654, SAO 170051[8] | |
| Database references | |
| SIMBAD | data |
Epsilon Leporis, Latinized from ε Leporis, formally named Ping,[9] is a third-magnitude star in the southern constellation Lepus. The apparent visual magnitude of +3.166[2] places it third in brightness among the stars in this constellation. Based upon parallax measurements, it is located at a distance of around 213 light-years (65 parsecs) from Earth.[1]
This is an evolved giant star with a stellar classification of K4 III[3] that has expanded to 40 times the Sun's radius. It is about 1.72 billion years old and has 1.70 times the mass of the Sun, with a luminosity 372[7] times as great. The outer atmosphere is cooler than the Sun's with an effective temperature of 4,131 K,[6] giving it the orange hue of a K-type star.[10] In terms of its composition, this star shows a similar abundance of elements other than hydrogen and helium to the Sun.[6]
The envelope of this star is undergoing oscillations that show up as changes in the star's radial velocity. Over long durations these follow a linear trend, in combination with shorter period oscillations occurring over a few days. These oscillations are unlikely to be the result of rotational module as that would imply a high rotation rate, which would display itself through strong X-ray emissions. Instead, they may be the result of solar-like and Mira-like oscillations.[11]
Nomenclature
[edit]Epsilon Leporis, Latinized from ε Leporis, is the star's Bayer designation.
In Chinese astronomy, ε Leporis forms with μ Leporis the asterism Ping (屏), representing a screen in front of a toilet.[12] The IAU Working Group on Star Names approved the name Ping for ε Leporis on 22 March 2026.[9]
References
[edit]- 1 2 3 4 5 van Leeuwen, F. (November 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 Gutierrez-Moreno, Adelina; et al. (1966), "A System of photometric standards", Publications of the Department of Astronomy University of Chile, 1, Publicaciones Universidad de Chile, Department de Astronomy: 1–17, Bibcode:1966PDAUC...1....1G
- 1 2 Houk, Nancy; Smith-Moore, M. (1978), "Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars", Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars, 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
- ↑ Wielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veröffentlichungen des Astronomischen Rechen-Instituts Heidelberg, 35 (35), Astronomisches Rechen-Institut Heidelberg: 1, Bibcode:1999VeARI..35....1W
- ↑ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- 1 2 3 4 da Silva, L.; et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars", Astronomy and Astrophysics, 458 (2): 609–623, arXiv:astro-ph/0608160, Bibcode:2006A&A...458..609D, doi:10.1051/0004-6361:20065105, S2CID 9341088.
- 1 2 di Mauro, M. P.; Cardini, D. (October 2006), "Asteroseismology of K giants", in Fletcher, Karen; Thompson, Michael (eds.), Proceedings of SOHO 18/GONG 2006/HELAS I, Beyond the spherical Sun (ESA SP-624), vol. 624, Sheffield, UK, p. 118, Bibcode:2006ESASP.624E.118D
{{citation}}: CS1 maint: location missing publisher (link) - ↑ "eps Lep". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2006-10-29.
- 1 2 "IAU Catalog of Star Names". Retrieved 23 March 2026.
- ↑ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on 2012-03-18, retrieved 2012-01-16
- ↑ Setiawan, J.; et al. (2006), "Multi-periodic oscillations of HD 32887 and HD 81797", Memorie della Società Astronomica Italiana, 77: 510, arXiv:astro-ph/0505184, Bibcode:2006MmSAI..77..510S
- ↑ Ridpath, Ian. "Star Tales – Lepus". Retrieved 23 March 2026.
