Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Lepus |
Right ascension | 05h 28m 14.72316s [1] |
Declination | −20° 45′ 33.9878″ [1] |
Apparent magnitude (V) | 2.813 [2] |
Characteristics | |
Spectral type | G5 II [3] |
U−B color index | +0.47 [4] |
B−V color index | +0.808 [2] |
R−I color index | +0.44 [5] |
Astrometry | |
Radial velocity (Rv) | −13.6 ± 0.9 [6] km/s |
Proper motion (μ) |
RA: −5.02
[1]
mas/
yr Dec.: −85.92 [1] mas/ yr |
Parallax (π) | 20.34 ± 0.18 mas [1] |
Distance | 160 ± 1
ly (49.2 ± 0.4 pc) [1] |
Absolute magnitude (MV) | −0.65 [7] |
Details | |
Mass | 2.948±0.031 [2] M☉ |
Radius | 12.573±0.153 [2] R☉ |
Luminosity | 171 [8] L☉ |
Surface gravity (log g) | 2.88 [2] cgs |
Temperature | 5,398 [2] K |
Metallicity [Fe/H] | −0.08±0.02 [2] dex |
Rotational velocity (v sin i) | 11 [9] km/s |
Age | 391±11 [2] Myr |
Other designations | |
Database references | |
SIMBAD | data |
Beta Leporis (β Leporis, abbreviated Beta Lep, β Lep), formally named Nihal /ˈnaɪ.æl/, [10] [11] is the second brightest star in the constellation of Lepus. [12]
Beta Leporis is the star's Bayer designation. It is also known by the traditional named Nihal, Arabic for "quenching their thirst". The occasional spelling Nibal appears to be due to a misreading. [13] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) [14] to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 [15] included a table of the first two batches of names approved by the WGSN; which included Nihal for this star.
In Chinese, 廁 (Cè), meaning Toilet, refers to an asterism consisting of β Leporis, α Leporis, γ Leporis and δ Leporis. [16] Consequently, the Chinese name for β Leporis itself is 廁二 (Cè èr), "the Second Star of Toilet". [17]
Based on parallax measurements from the Hipparcos astrometry satellite, [18] this star is located about 160 light-years (49 parsecs) from the Earth. It has an apparent visual magnitude of 2.81 [2] and a stellar classification of G5 II. [3] The mass of this star is 3 times the mass of the Sun and it is about 390 million years old, [2] which is the sufficient time for a star this massive to consume the hydrogen at its core and evolve away from the main sequence, becoming a G-type bright giant. [3] Currently, it has expanded to 12.6 times the Sun's size [2] and is emitting 171 times its luminosity. [8]
This is a double star system and may be a binary, whereby the second star has a brightness of 7.34 mag. [19] Using adaptive optics on the AEOS telescope at Haleakala Observatory, the pair was found to be separated by an angle of 2.58 arcseconds at a position angle of 1.4°. [20] Component B has been observed to fluctuate in brightness and is catalogued as suspected variable star NSV 2008. [21]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Lepus |
Right ascension | 05h 28m 14.72316s [1] |
Declination | −20° 45′ 33.9878″ [1] |
Apparent magnitude (V) | 2.813 [2] |
Characteristics | |
Spectral type | G5 II [3] |
U−B color index | +0.47 [4] |
B−V color index | +0.808 [2] |
R−I color index | +0.44 [5] |
Astrometry | |
Radial velocity (Rv) | −13.6 ± 0.9 [6] km/s |
Proper motion (μ) |
RA: −5.02
[1]
mas/
yr Dec.: −85.92 [1] mas/ yr |
Parallax (π) | 20.34 ± 0.18 mas [1] |
Distance | 160 ± 1
ly (49.2 ± 0.4 pc) [1] |
Absolute magnitude (MV) | −0.65 [7] |
Details | |
Mass | 2.948±0.031 [2] M☉ |
Radius | 12.573±0.153 [2] R☉ |
Luminosity | 171 [8] L☉ |
Surface gravity (log g) | 2.88 [2] cgs |
Temperature | 5,398 [2] K |
Metallicity [Fe/H] | −0.08±0.02 [2] dex |
Rotational velocity (v sin i) | 11 [9] km/s |
Age | 391±11 [2] Myr |
Other designations | |
Database references | |
SIMBAD | data |
Beta Leporis (β Leporis, abbreviated Beta Lep, β Lep), formally named Nihal /ˈnaɪ.æl/, [10] [11] is the second brightest star in the constellation of Lepus. [12]
Beta Leporis is the star's Bayer designation. It is also known by the traditional named Nihal, Arabic for "quenching their thirst". The occasional spelling Nibal appears to be due to a misreading. [13] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) [14] to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 [15] included a table of the first two batches of names approved by the WGSN; which included Nihal for this star.
In Chinese, 廁 (Cè), meaning Toilet, refers to an asterism consisting of β Leporis, α Leporis, γ Leporis and δ Leporis. [16] Consequently, the Chinese name for β Leporis itself is 廁二 (Cè èr), "the Second Star of Toilet". [17]
Based on parallax measurements from the Hipparcos astrometry satellite, [18] this star is located about 160 light-years (49 parsecs) from the Earth. It has an apparent visual magnitude of 2.81 [2] and a stellar classification of G5 II. [3] The mass of this star is 3 times the mass of the Sun and it is about 390 million years old, [2] which is the sufficient time for a star this massive to consume the hydrogen at its core and evolve away from the main sequence, becoming a G-type bright giant. [3] Currently, it has expanded to 12.6 times the Sun's size [2] and is emitting 171 times its luminosity. [8]
This is a double star system and may be a binary, whereby the second star has a brightness of 7.34 mag. [19] Using adaptive optics on the AEOS telescope at Haleakala Observatory, the pair was found to be separated by an angle of 2.58 arcseconds at a position angle of 1.4°. [20] Component B has been observed to fluctuate in brightness and is catalogued as suspected variable star NSV 2008. [21]