Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Chamaeleon |
Right ascension | 11h 18m 34.40370s [1] |
Declination | −79° 40′ 07.1370″ [1] |
Apparent magnitude (V) | 6.35±0.01 [2] |
Characteristics | |
Evolutionary stage | main sequence [1] |
Spectral type | A8 IIIm: [3] |
U−B color index | +0.08 [4] |
B−V color index | +0.26 [4] |
Astrometry | |
Radial velocity (Rv) | −4±2.1 [5] km/s |
Proper motion (μ) |
RA: +46.293
mas/
yr
[1] Dec.: −37.910 mas/ yr [1] |
Parallax (π) | 15.7985 ± 0.069 mas [1] |
Distance | 206.4 ± 0.9
ly (63.3 ± 0.3 pc) |
Absolute magnitude (MV) | +2.42 [6] |
Details | |
Mass | 1.75±0.07 [7] M☉ |
Radius | 1.85±0.06 [8] R☉ |
Luminosity | 8.41 [9] L☉ |
Surface gravity (log g) | 4.20±0.04 [7] cgs |
Temperature | 7,540±276 [10] K |
Metallicity [Fe/H] | −0.03 [11] dex |
Age | 1.06 [11] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 98617, also known HR 4385, is a double star located in the southern circumpolar constellation Chamaeleon. The system has a combined apparent magnitude of 6.35, [2] placing it near the limit for naked eye. The system is located relatively close at a distance of 206 light years [1] but is approaching the Solar System with a fairly constrained radial velocity of −4 km/s. [5] At its current distance, HD 98617 brightness is diminished by 0.29 magnitudes due to interstellar dust. [14]
The system's nature as a double star was first observed in a 1991 Hipparcos multiplicity survey. Their current separation is six-tenths of an arcsecond, making it difficult to measure the properties of the individual components. Nevertheless, the 10th magnitude companion is located along a position angle of 237° as of 2018. [15]
The primary has a stellar classification of A8 IIIm:, indicating that it is an evolved Am star (with uncertainty). [3] However, Renson and Manfroid (2009) lists its chemical peculiarity to be doubtful. [16] It has 1.75 times the mass of the Sun [7] and 1.85 times its girth. [8] It radiates 8.41 times the luminosity of the Sun [9] from its photosphere at an effective temperature of 7,540 K, [10] giving it a white hue. It is estimated to be a billion years old and has a solar metallicity. [11] The aforementioned parameters belong to an A-type main-sequence star instead of a giant star and Gaia DR3 even models it as such. [1]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Chamaeleon |
Right ascension | 11h 18m 34.40370s [1] |
Declination | −79° 40′ 07.1370″ [1] |
Apparent magnitude (V) | 6.35±0.01 [2] |
Characteristics | |
Evolutionary stage | main sequence [1] |
Spectral type | A8 IIIm: [3] |
U−B color index | +0.08 [4] |
B−V color index | +0.26 [4] |
Astrometry | |
Radial velocity (Rv) | −4±2.1 [5] km/s |
Proper motion (μ) |
RA: +46.293
mas/
yr
[1] Dec.: −37.910 mas/ yr [1] |
Parallax (π) | 15.7985 ± 0.069 mas [1] |
Distance | 206.4 ± 0.9
ly (63.3 ± 0.3 pc) |
Absolute magnitude (MV) | +2.42 [6] |
Details | |
Mass | 1.75±0.07 [7] M☉ |
Radius | 1.85±0.06 [8] R☉ |
Luminosity | 8.41 [9] L☉ |
Surface gravity (log g) | 4.20±0.04 [7] cgs |
Temperature | 7,540±276 [10] K |
Metallicity [Fe/H] | −0.03 [11] dex |
Age | 1.06 [11] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 98617, also known HR 4385, is a double star located in the southern circumpolar constellation Chamaeleon. The system has a combined apparent magnitude of 6.35, [2] placing it near the limit for naked eye. The system is located relatively close at a distance of 206 light years [1] but is approaching the Solar System with a fairly constrained radial velocity of −4 km/s. [5] At its current distance, HD 98617 brightness is diminished by 0.29 magnitudes due to interstellar dust. [14]
The system's nature as a double star was first observed in a 1991 Hipparcos multiplicity survey. Their current separation is six-tenths of an arcsecond, making it difficult to measure the properties of the individual components. Nevertheless, the 10th magnitude companion is located along a position angle of 237° as of 2018. [15]
The primary has a stellar classification of A8 IIIm:, indicating that it is an evolved Am star (with uncertainty). [3] However, Renson and Manfroid (2009) lists its chemical peculiarity to be doubtful. [16] It has 1.75 times the mass of the Sun [7] and 1.85 times its girth. [8] It radiates 8.41 times the luminosity of the Sun [9] from its photosphere at an effective temperature of 7,540 K, [10] giving it a white hue. It is estimated to be a billion years old and has a solar metallicity. [11] The aforementioned parameters belong to an A-type main-sequence star instead of a giant star and Gaia DR3 even models it as such. [1]