HN Librae

HN Librae

A visual band light curve for HN Librae, adapted from Weis (1994)[1]
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Libra
Right ascension 14h 34m 16.81166s[2]
Declination −12° 31′ 10.4145″[2]
Apparent magnitude (V) 11.32[3]
Characteristics
Spectral type M4.0V[4]
B−V color index 1.633±0.052[3]
Variable type BY Dra
Astrometry
Radial velocity (Rv)−1.36±0.20[2] km/s
Proper motion (μ) RA: −355.138 mas/yr[2]
Dec.: 593.040 mas/yr[2]
Parallax (π)159.9225 ± 0.0546 mas[2]
Distance20.395 ± 0.007 ly
(6.253 ± 0.002 pc)
Absolute magnitude (MV)12.41[3]
Details[4]
Mass0.291±0.013 M☉
Radius0.299±0.009 R☉
Luminosity (bolometric)0.010106±0.000069 L☉
Surface gravity (log g)4.76±0.13 cgs
Temperature3347±50 K
Metallicity [Fe/H]−0.18±0.15 dex
Rotation96±2 d
Rotational velocity (v sin i)<2.0 km/s
Age0.8–8.0 Gyr
Other designations
HN Lib, BD−11 3759, GJ 555, HIP 71253, Ci 20 870, LFT 1120, LHS 2945, LPM 532, LTT 5759, NLTT 37751, PLX 3296, PM 14316-1219, Wolf 1481, TYC 5572-804-1, GSC 05572-00804, 2MASS J14341683-1231106[5]
Database references
SIMBADdata
HN Librae is located in the constellation Libra
HN Librae is located in the constellation Libra
HN Librae
Location of HN Librae in the constellation Libra

HN Librae, also known as Gliese 555, is a small star with one or more orbiting exoplanets in the constellation Libra. With an apparent visual magnitude of 11.32,[3] it can only be viewed through a telescope. The system is located at a distance of 20.4 light years based on parallax measurements, but is drifting closer to the Sun with a radial velocity of −1.4 km/s.[2] It does not appear to belong to any known stellar moving group or association.[4]

This is an M-type main-sequence star, a red dwarf, with a stellar classification of M4.0V. The chromosphere of this star is weakly active, causing starspots that vary the stellar luminosity as it rotates.[4] It has 29% of the mass of the Sun and 30% of the Sun's girth. On average, the star is radiating just 1% of the luminosity of the Sun from its photosphere at an effective temperature of 3,347 K. The star is spinning slowly with a rotation period of around 96 days.[4]

  1. ^ Cite error: The named reference Weis was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
  4. ^ a b c d e Cite error: The named reference González-Álvarez2023 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).