HD 111395
Star in the constellation Coma Berenices
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HD 111395 is a single,[12] variable star in the northern constellation of Coma Berenices. It has the variable star designation LW Comae Berenices;[5] HD 111395 is the Henry Draper Catalogue designation. The star has a yellow hue and is just bright enough to be barely visible to the naked eye with an apparent visual magnitude that fluctuates around 6.29.[2] Based upon parallax measurements, it is located at a distance of 55.8 light years from the Sun.[3] The star is drifting closer with a radial velocity of −8.9 km/s.[6] It is a member of the Eta Chamaeleontis stellar kinematic group.[13]
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Coma Berenices[2] |
| Right ascension | 12h 48m 47.048s[3] |
| Declination | +24° 50′ 24.82″[3] |
| Apparent magnitude (V) | 6.29[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | G7V[4] |
| B−V color index | 0.703±0.002[2] |
| Variable type | BY Dra[5] |
| Astrometry | |
| Radial velocity (Rv) | −8.936±0.0064[6] km/s |
| Proper motion (μ) | RA: −334.908 mas/yr[3] Dec.: −105.517 mas/yr[3] |
| Parallax (π) | 58.4858±0.0293 mas[3] |
| Distance | 55.77 ± 0.03 ly (17.098 ± 0.009 pc) |
| Absolute magnitude (MV) | 5.15[2] |
| Details | |
| Mass | 1.08±0.04[7] M☉ |
| Radius | 0.93±0.01[8] R☉ |
| Luminosity | 0.799±0.001[8] L☉ |
| Surface gravity (log g) | 4.543±0.05[7] cgs |
| Temperature | 5,649+38 −17[8] K |
| Metallicity [Fe/H] | 0.08±0.02[7] dex |
| Rotational velocity (v sin i) | 3.8±0.8[7] km/s |
| Age | 1.0[9] or 1.01−1.73[10] Gyr |
| Other designations | |
| LW Com, BD+25°2568, FK5 3021, GJ 486.1, HD 111395, HIP 62523, HR 4864, SAO 82511[11] | |
| Database references | |
| SIMBAD | data |
This object is a G-type main-sequence star with a stellar classification of G7V.[4] Klaus G. Strassmeier et al. announced their discovery that HD 111395 is a variable star, in 1997.[1] It was given its variable star designation in 2006.[14] It is a BY Draconis variable that varies in brightness by about 0.10 magnitude over a period of 15.8 days,[5] which is interpreted as the rotation period of the star. (Messina et al. (2003) suspect the actual rotation period may be half that: 7.9 days.[15]) It has an active chromosphere[1] and is a source for X-ray emission.[16]
The star is around a billion years old with a projected rotational velocity of 3.8 km/s.[7] It has slightly above solar metallicity − the term astronomers use for the relative abundance of elements other than hydrogen and helium. The mass of the star is 8% greater than the Sun,[7] but it has 93% of the Sun's radius.[8] It is radiating 80% of the luminosity of the Sun from its photosphere at an effective temperature of 5649 K.[8] An infrared excess indicates a cold debris disk is orbiting the star at a distance of 17.48 AU with a mean temperature of 60 K. The disk has an estimated mass of 5.86×10−6 M🜨.[9]