Epsilon Leporis
Star in the constellation Lepus
From Wikipedia, the free encyclopedia
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]
 | |
| 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] |
| 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 | |
| ε Lep, 2 Leporis, NSV 1826, BD−22°1000, FK5 186, HD 32887, HIP 23685, HR 1654, SAO 170051[8] | |
| Database references | |
| SIMBAD | data |
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]