Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Draco |
Right ascension | 18h 23m 54.60641s [1] |
Declination | +58° 48′ 02.6446″ [1] |
Apparent magnitude (V) | 5.034 [2] (5.06 + 8.07) [3] |
Characteristics | |
Spectral type | A1V + F5V [4] |
U−B color index | +0.06 [5] |
B−V color index | +0.10 [5] |
Astrometry | |
Radial velocity (Rv) | −24.53±0.23 [6] km/s |
Proper motion (μ) | RA: −37.82 [1] mas/yr Dec.: +61.60 [1] mas/yr |
Parallax (π) | 17.71 ± 0.35 mas [1] |
Distance | 184 ± 4 ly (56 ± 1 pc) |
Absolute magnitude (MV) | 1.31 / 4.32 [7] |
Orbit [3] | |
Period (P) | 3962.50 ± 209.26 yr |
Semi-major axis (a) | 6.621 ± 0.325″ |
Eccentricity (e) | 0.553 ± 0.005 |
Inclination (i) | 107.7 ± 0.12° |
Longitude of the node (Ω) | 179.9 ± 0.10° |
Periastron epoch (T) | 5671.40 ± 12.08 |
Argument of periastron (ω) (secondary) | 128.0 ± 2.18° |
Details | |
39 Dra A | |
Mass | 2.12 [7] M☉ |
Radius | 2.3 [8] R☉ |
Surface gravity (log g) | 4.05 ± 0.07 [8] cgs |
Temperature | 8710 [8] K |
39 Dra B | |
Mass | 1.18 [7] M☉ |
Other designations | |
Database references | |
SIMBAD | 39 Dra |
39 Dra A | |
39 Dra B |
39 Draconis is a wide binary star system in the northern circumpolar constellation of Draco. It has the Bayer designation b Draconis, while 39 Draconis is the Flamsteed designation. This system is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude of 5.0. [2] Parallax measurements made by the Hipparcos spacecraft put it at a distance of 184 light-years, or 56 parsecs away from the Sun. [1] The system is moving closer to the Earth with a heliocentric radial velocity of -24.5 km/s. [6]
The two components of 39 Draconis have an angular separation of 6.621″ and take almost 4,000 years to orbit each other. [3] The primary star is an early A-type main-sequence star, having 2.12 times the mass of the Sun with a visual magnitude of 5.06 [3] The secondary is a magnitude 8.07 [3] F-type main-sequence star, and has 1.18 times the mass of the Sun. [7]
The 8th-magnitude star HD 238865 is listed in double star catalogues as component C. [9] It is separated from the other two stars by 90″ and lies at about the same distance. [10] It is itself a spectroscopic binary with an F8 primary and a red dwarf secondary orbiting every 2.7 days. [11] [12]
Mu Draconis is a multiple star system near the head of the constellation of Draco. With a combined magnitude of 4.92, it is visible to the naked eye. Based on parallax estimates by the Hipparcos spacecraft, it is located approximately 89 light-years from the Sun.
Xi Serpentis, Latinized from ξ Serpentis, is a triple star system in the Serpens Cauda (tail) section of the equatorial constellation Serpens. Based upon an annual parallax shift of 30.98 mas as seen from Earth, it is located 105.3 light years from the Sun. The star system is visible to the naked eye with a base apparent visual magnitude of +3.54. It is moving closer to the Sun and will make perihelion passage at a distance of 27 ly (8.2 pc) in around 690,000 years.
Omega Ursae Majoris is the Bayer designation for a binary star system in the northern circumpolar constellation of Ursa Major. It is visible to the naked eye with an apparent visual magnitude of 4.61. Based upon an annual parallax shift of 13.24 mas, it is roughly 246 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.11 due to interstellar dust.
Tau Ursae Majoris (τ UMa) is the Bayer designation for a binary star in the northern circumpolar constellation of Ursa Major. It is visible to the naked eye, having an apparent visual magnitude of 4.66. With an annual parallax shift of 25.82 mas, it is located about 126 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.19 due to interstellar dust.
9 Aurigae is a star system in Auriga (constellation). It has an apparent magnitude of about 5, making it visible to the naked eye in many suburban skies. Parallax estimates made by the Hipparcos spacecraft put it at about 86 light-years from the solar system, although individual Gaia Data Release 3 parallaxes place all three components at 88 light years.
14 Aurigae is a quadruple star system located 269 light years away from the Sun in the zodiac constellation of Auriga. It has the variable star designation KW Aurigae, whereas 14 Aurigae is the Flamsteed designation. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.01. The system is moving closer to the Sun with a heliocentric radial velocity of −9 km/s.
31 Camelopardalis is a binary star system in the northern circumpolar constellation of Camelopardalis. It is visible to the naked eye as a dim point of light with a peak apparent visual magnitude of +5.12. Parallax measurements provide a distance estimate of approximately 460 light years away from the Sun, and the system is drifting closer to the Earth with a radial velocity of −3 km/s.
HR 3220 is a binary star system in the southern constellation of Carina. It has the Bayer designation B Carinae; HR 3220 is the designation from the Bright Star Catalogue. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude of 4.75. Based upon parallax measurements, it is located at a distance of 59 light years from the Sun. The system is drifting further away with a radial velocity of +24 km/s.
5 Tauri is a binary star in the zodiac constellation of Taurus, located approximately 530 light years from the Sun. It is visible to the naked eye as a faint orange-hued star with an apparent visual magnitude of +4.14. It is moving further from the Earth with a heliocentric radial velocity of +14 km/s.
δ Doradus is a star in the southern constellation of Dorado. Based upon an annual parallax shift of 21.80 mas as seen from Earth, it is located around 150 light years from the Sun. The star is visible to the naked eye with an apparent visual magnitude of +4.34.
V538 Aurigae is a single star in the northern constellation of Auriga. With an apparent visual magnitude of 6.23, this star requires good dark sky conditions to view with the naked eye. It is located at a distance of 40.0 light-years (12.3 pc) from Sun based on parallax. The star is drifting further away with a radial velocity of 0.9 km/s. It is a member of the Local Association, and is most likely a thin disk star.
Theta Draconis, a name Latinized from θ Draconis, is a binary star system in the northern circumpolar constellation of Draco. It is faintly visible to the naked eye at night with an apparent visual magnitude of 4.12. Parallax measurements place it at an estimated distance of 68.6 light-years from the Sun, and it is drifting closer with a radial velocity of −8 km/s. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.464″ per year. O. J. Eggen included this star as a member of the NGC 1901 supercluster based on its space motion.
HR 7578 is a binary star in the constellation of Sagittarius. Their combined apparent magnitude is 6.18. Parallax measurements by the Gaia spacecraft put the system at 46.01 light-years away, making this a nearby system.
Chi Ceti , is the Bayer designation for a double star in the equatorial constellation of Cetus. They appear to be common proper motion companions, sharing a similar motion through space. The brighter component, HD 11171, is visible to the naked eye with an apparent visual magnitude of 4.66, while the fainter companion, HD 11131, is magnitude 6.75. Both lie at roughly the same distance, with the brighter component lying at an estimated distance of 75.6 light years from the Sun based upon an annual parallax shift of 43.13 mass.
Upsilon4 Eridani is a close binary star system in the constellation Eridanus. It is visible to the naked eye with an apparent visual magnitude of 3.56. Based upon parallax measurements, the pair are located around 54.6 parsecs (178 ly) from the Sun.
1 Geminorum is a star in the constellation Gemini. Its apparent magnitude is 4.15.
Lambda Lupi, Latinized from λ Lupi, is a triple star system in the southern constellation of Lupus. It is visible to the naked eye with a combined apparent visual magnitude of 4.04. Based upon an annual parallax shift of just 4.20 mas as seen from Earth, it is located roughly 800 light years from the Sun. The system has a peculiar velocity of 27.4±4.9 km/s relative to its neighbors, making it a candidate runaway star system. It is a member of the Upper Centaurus–Lupus sub-group in the Scorpius–Centaurus OB association.
Mu Lupi is a system of three or four stars in the southern constellation of Lupus. It is visible to the naked eye with an apparent visual magnitude of 4.29 and lies roughly 340 light-years from the Sun.
16 Serpentis is a binary star system in the Serpens Caput portion of the equatorial constellation of Serpens, located 228 light years from the Sun. It is visible to the naked eye as a fain, orange-hued star with an apparent visual magnitude of 5.261. The system is moving further from the Earth with a heliocentric radial velocity of +3 km/s.
c Ursae Majoris is the Bayer designation for a double-lined spectroscopic binary star system in the northern constellation of Ursa Major. It has an apparent visual magnitude of 5.18, which indicates that is visible to the naked eye. Parallax measurements yield an estimated distance of 66 light years from the Sun. The star is moving closer to the Earth with a heliocentric radial velocity of −14 km/s.