Epsilon Leporis

ε Leporis
Location of ε Leporis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
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]
Distance209 ± 1 ly
(64.1 ± 0.4 pc)
Absolute magnitude (MV)–1.02 ± 0.10[6]
Details[6]
Mass1.70±0.19 M☉
Radius40.1±3.2 R☉
Luminosity372[7] L☉
Surface gravity (log g)1.43±0.09 cgs
Temperature4,131 K
Metallicity [Fe/H]–0.02 dex
Age1.72±0.47 Gyr
Other designations
ε Lep, 2 Leporis, NSV 1826, BD−22° 1000, FK5 186, HD 32887, HIP 23685, HR 1654, SAO 170051[8]
Database references
SIMBADdata

Epsilon Leporis, Latinized from ε Leporis, 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.[9] 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.[10]

  1. ^ a b c d e Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference sps1966 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference scfs was invoked but never defined (see the help page).
  5. ^ 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.
  6. ^ a b c d Cite error: The named reference aaa458_2_609 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference esa_sp_624 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference csiro was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference msai77_510 was invoked but never defined (see the help page).