Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Delphinus |
Right ascension | 20h 30m 58.26388s [1] |
Declination | +20° 36′ 23.0762″ [1] |
Apparent magnitude (V) | 6.20±0.01 [2] |
Characteristics | |
Spectral type | kA1 hA9 mF2 [3] |
U−B color index | +0.13 [4] |
B−V color index | +0.12 [4] |
Astrometry | |
Radial velocity (Rv) | −40.1±1.6 [5] km/s |
Proper motion (μ) |
RA: +95.633
mas/
yr
[1] Dec.: +58.78 mas/ yr [1] |
Parallax (π) | 11.3074 ± 0.0337 mas [1] |
Distance | 288.4 ± 0.9
ly (88.4 ± 0.3 pc) |
Absolute magnitude (MV) | +1.53 [6] |
Details | |
Mass | 2.05+0.38 −0.24 [7] M☉ |
Radius | 2.15±0.11 [8] R☉ |
Luminosity | 38.96+0.36 −0.42 [1] L☉ |
Surface gravity (log g) | 4.08 [9] cgs |
Temperature | 8,454 [10] K |
Metallicity [Fe/H] | −0.11 [11] dex |
Rotational velocity (v sin i) | 18.0±0.6 [9] km/s |
Age | 631 [12] Myr |
Other designations | |
Database references | |
SIMBAD | data |
HD 195479, also designated as HR 7839, is a solitary star located in the northern constellation Delphinus, the dolphin. It has an apparent magnitude of 6.20, [2] placing it near the limit for naked eye visibility, even under ideal conditions. The object is located relatively close at a distance of 288 light-years based on Gaia DR3 parallax measurements [1] and it is drifting closer with a heliocentric radial velocity of −40.1 km/s. [5] At its current distance, HD 195479's brightness is diminished by an interstellar extinction of 0.27 magnitudes [14] and it has an absolute magnitude of +1.53. [6]
HD 195479 is an Am star with a stellar classification of kA1hA9mF2. [3] The notion indicates that it has the calcium K-lines of an A1 star, the hydrogen lines of an A9 star, and the metallic lines of a F2 star. It has 2.05 times the mass of the Sun [7] and 2.15 times the radius of the Sun. [8] It radiates 38.96 times the luminosity of the Sun [1] from its photosphere at an effective temperature of 8,454 K, [10] giving it white hue when viewed in the night sky. HD 195479 is deficient in iron, having an abundance 77.6% of the Sun's. [11] It is estimated to be 631 million years old [12] and it spins modestly with a projected rotational velocity of 18.0 km/s, [9] common for Am stars.
The star has two optical companions: a 12th magnitude star designated B located 5.7" away along a position angle of 88° and a 13th magnitude star designated C located 55.9" away along a position angle of 206°. [15] They were both observed by American astronomer Sherburne Wesley Burnham during the late 19th century. [16] B and C are both background stars that are far more distant than HD 195479. [17] [18]
Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Delphinus |
Right ascension | 20h 30m 58.26388s [1] |
Declination | +20° 36′ 23.0762″ [1] |
Apparent magnitude (V) | 6.20±0.01 [2] |
Characteristics | |
Spectral type | kA1 hA9 mF2 [3] |
U−B color index | +0.13 [4] |
B−V color index | +0.12 [4] |
Astrometry | |
Radial velocity (Rv) | −40.1±1.6 [5] km/s |
Proper motion (μ) |
RA: +95.633
mas/
yr
[1] Dec.: +58.78 mas/ yr [1] |
Parallax (π) | 11.3074 ± 0.0337 mas [1] |
Distance | 288.4 ± 0.9
ly (88.4 ± 0.3 pc) |
Absolute magnitude (MV) | +1.53 [6] |
Details | |
Mass | 2.05+0.38 −0.24 [7] M☉ |
Radius | 2.15±0.11 [8] R☉ |
Luminosity | 38.96+0.36 −0.42 [1] L☉ |
Surface gravity (log g) | 4.08 [9] cgs |
Temperature | 8,454 [10] K |
Metallicity [Fe/H] | −0.11 [11] dex |
Rotational velocity (v sin i) | 18.0±0.6 [9] km/s |
Age | 631 [12] Myr |
Other designations | |
Database references | |
SIMBAD | data |
HD 195479, also designated as HR 7839, is a solitary star located in the northern constellation Delphinus, the dolphin. It has an apparent magnitude of 6.20, [2] placing it near the limit for naked eye visibility, even under ideal conditions. The object is located relatively close at a distance of 288 light-years based on Gaia DR3 parallax measurements [1] and it is drifting closer with a heliocentric radial velocity of −40.1 km/s. [5] At its current distance, HD 195479's brightness is diminished by an interstellar extinction of 0.27 magnitudes [14] and it has an absolute magnitude of +1.53. [6]
HD 195479 is an Am star with a stellar classification of kA1hA9mF2. [3] The notion indicates that it has the calcium K-lines of an A1 star, the hydrogen lines of an A9 star, and the metallic lines of a F2 star. It has 2.05 times the mass of the Sun [7] and 2.15 times the radius of the Sun. [8] It radiates 38.96 times the luminosity of the Sun [1] from its photosphere at an effective temperature of 8,454 K, [10] giving it white hue when viewed in the night sky. HD 195479 is deficient in iron, having an abundance 77.6% of the Sun's. [11] It is estimated to be 631 million years old [12] and it spins modestly with a projected rotational velocity of 18.0 km/s, [9] common for Am stars.
The star has two optical companions: a 12th magnitude star designated B located 5.7" away along a position angle of 88° and a 13th magnitude star designated C located 55.9" away along a position angle of 206°. [15] They were both observed by American astronomer Sherburne Wesley Burnham during the late 19th century. [16] B and C are both background stars that are far more distant than HD 195479. [17] [18]