68 Draconis

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68 Draconis
Observation data
Epoch J2000       Equinox J2000
Constellation Draco
Right ascension 20h 11m 34.872s [1]
Declination +62° 04 42.77 [1]
Apparent magnitude  (V)5.69 [2]
Characteristics
Spectral type F5 V [2]
B−V color index 0.48 [3]
Astrometry
Radial velocity (Rv)–14.6 [4]  km/s
Proper motion (μ)RA: +142.267  mas/yr [1]
Dec.: +72.842  mas/yr [1]
Parallax (π)20.9232 ± 0.065  mas [1]
Distance 155.9 ± 0.5  ly
(47.8 ± 0.1  pc)
Absolute magnitude  (MV)2.33 [5]
Details
Mass 1.15 [6]   M
Luminosity 10.73 [7]   L
Surface gravity (log g)3.95 [3]   cgs
Temperature 6,137 [3]   K
Metallicity [Fe/H]0.20 [5]   dex
Rotational velocity (v sin i)15.1 [3]  km/s
Age 1.7 [5]   Gyr
Other designations
68 Dra, BD+61° 1983, HD  192455, HIP  99500, HR  7727, SAO  18751 [8]
Database references
SIMBAD data

68 Draconis is the Flamsteed designation for a star in the northern circumpolar constellation of Draco. It has an apparent visual magnitude of 5.69, [2] so, according to the Bortle scale, it is faintly visible to the naked eye from suburban skies at night. Measurements made with the Gaia spacecraft show an annual parallax shift of 0.0209232 , [1] which is equivalent to a distance of around 156 ly (48 pc) from the Sun. It is moving closer to the Earth with a heliocentric radial velocity of –14.6 km/s. [4] The star has a relatively high proper motion, traversing the celestial sphere at a rate of 0.150″ per year. [9]

The stellar classification of 68 Draconis is F5 V, [2] indicating that it is a main sequence star that is fusing hydrogen into helium at its core to generate energy. The star appears to be over-luminous for a member of its class, being 0.73 magnitudes brighter than expected. This may indicate that this is a binary system with an unresolved secondary component. [2] It has 15% [6] more mass than the Sun but is less than half as old, with an estimated age of 1.7 billion years. [5] The star is radiating 11 [7] times the Sun's luminosity from its photosphere at an effective temperature of 6,137 K, [3] giving it the yellow-white hue of an F-type star. [10]

Related Research Articles

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39 Aquarii is a star in the zodiac constellation of Aquarius. 39 Aquarii is its Flamsteed designation. It is a faint naked eye star with an apparent visual magnitude of 6.03. Based upon an annual parallax shift of 23.78 measured with a 3% margin of error, this star is at a distance of around 137 light-years from Earth. It is a double star with a magnitude 9.3 companion at an angular separation of 0.6 arcseconds along a position angle of 257°.

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π2 Gruis, Latinised as Pi2 Gruis, is a binary star system in the southern constellation of Grus. It is faintly visible to the naked eye as a yellow-white hued star with an apparent visual magnitude of 5.622. Based upon an annual parallax shift of 25.1 mas as seen from the Earth, the system is located 130 light years from the Sun.

10 Canum Venaticorum is the Flamsteed designation for an ordinary star in the northern constellation of Canes Venatici. It has an apparent visual magnitude of 5.95, which, according to the Bortle scale, can be faintly seen with the naked eye from suburban locations. Based upon an annual parallax shift of 0.057 arcseconds, this system is 57.26 light-years from Sun. It is drifting further away with a radial velocity of +80 km/s.

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HD 219623 is a solitary star in the northern circumpolar constellation of Cassiopeia. HD 219623 is its Henry Draper Catalogue designation. It has an apparent visual magnitude of 5.59, which lies in the brightness range that is visible to the naked eye. According to the Bortle scale, it can be observed from dark suburban skies. Parallax measurements place it at an estimated distance of around 67.2 light years. It has a relatively high proper motion, advancing 262 mas per year across the celestial sphere.

HD 28246 is a solitary star located in the southern constellation Caelum. It has an apparent magnitude of 6.38, placing it near the max visibility to the unaided eye. The star is located relatively close at a distance of about 122 light years but is recceding with a heliocentric radial velocity of 14.9 km/s.

16 Delphini is a star in the equatorial constellation Delphinus. It has an apparent magnitude of 5.54, making it faintly visible to the naked eye. The star is relatively close at a distance of 198 light years but is receding with a poorly constrained radial velocity of 2 km/s.

References

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