Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Sagittarius |
Right ascension | 18h 25m 01.42751s [1] |
Declination | −30° 45′ 23.6292″ [1] |
Apparent magnitude (V) | 5.58 [2] |
Characteristics | |
Evolutionary stage | giant star |
Spectral type | K0 III [3] |
B−V color index | 1.138 [4] |
Astrometry | |
Radial velocity (Rv) | −18.7±2.9 [2] km/s |
Proper motion (μ) |
RA: −135.019
[1]
mas/
yr Dec.: −70.932 [1] mas/ yr |
Parallax (π) | 5.9260 ± 0.2434 mas [1] |
Distance | 550 ± 20
ly (169 ± 7 pc) |
Absolute magnitude (MV) | −0.93 [4] |
Details | |
Radius | 8.9 [5] R☉ |
Luminosity | 309.45 [2] L☉ |
Surface gravity (log g) | 1.50 [4] cgs |
Temperature | 4,341 [4] K |
Metallicity [Fe/H] | −0.79 [4] dex |
Rotational velocity (v sin i) | 1.0 [4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
18 Sagittarii is a single [7] star in zodiac constellation of Sagittarius, [6] located around 550 light years away from the Sun based on parallax. [1] It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.58. [2] This object is moving closer to the Earth with a heliocentric radial velocity of −19 km/s. [2]
This is an aging giant star with a stellar classification of K0 III, [3] which indicates it has exhausted the hydrogen at its core and evolved away from the main sequence. It has expanded to about 9 [5] times the Sun's radius and is radiating 309 [2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,341. [4] There is a much lower abundance of iron in the spectrum compared to the Sun. [4]
Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Sagittarius |
Right ascension | 18h 25m 01.42751s [1] |
Declination | −30° 45′ 23.6292″ [1] |
Apparent magnitude (V) | 5.58 [2] |
Characteristics | |
Evolutionary stage | giant star |
Spectral type | K0 III [3] |
B−V color index | 1.138 [4] |
Astrometry | |
Radial velocity (Rv) | −18.7±2.9 [2] km/s |
Proper motion (μ) |
RA: −135.019
[1]
mas/
yr Dec.: −70.932 [1] mas/ yr |
Parallax (π) | 5.9260 ± 0.2434 mas [1] |
Distance | 550 ± 20
ly (169 ± 7 pc) |
Absolute magnitude (MV) | −0.93 [4] |
Details | |
Radius | 8.9 [5] R☉ |
Luminosity | 309.45 [2] L☉ |
Surface gravity (log g) | 1.50 [4] cgs |
Temperature | 4,341 [4] K |
Metallicity [Fe/H] | −0.79 [4] dex |
Rotational velocity (v sin i) | 1.0 [4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
18 Sagittarii is a single [7] star in zodiac constellation of Sagittarius, [6] located around 550 light years away from the Sun based on parallax. [1] It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.58. [2] This object is moving closer to the Earth with a heliocentric radial velocity of −19 km/s. [2]
This is an aging giant star with a stellar classification of K0 III, [3] which indicates it has exhausted the hydrogen at its core and evolved away from the main sequence. It has expanded to about 9 [5] times the Sun's radius and is radiating 309 [2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,341. [4] There is a much lower abundance of iron in the spectrum compared to the Sun. [4]