8 Cygni

Last updated
8 Cygni
Observation data
Epoch J2000        Equinox J2000
Constellation Cygnus
Right ascension 19h 31m 46.32184s [1]
Declination +34° 27 10.6874 [1]
Apparent magnitude  (V)4.75 [2]
Characteristics
Spectral type B3 IV [3]
B−V color index −0.155 [2]
Astrometry
Radial velocity (Rv)−21.20±0.1 [4]  km/s
Proper motion (μ)RA: 1.16 [1]   mas/yr
Dec.: −3.47 [1]   mas/yr
Parallax (π)3.79 ± 0.16  mas [1]
Distance 860 ± 40  ly
(260 ± 10  pc)
Details
Mass 6.40 [5]   M
Radius 6.50 [5]   R
Luminosity 2,512 [5]   L
Surface gravity (log g)3.62 [5]   cgs
Temperature 16,100 [5]   K
Metallicity [Fe/H]+0.25 [5]   dex
Rotational velocity (v sin i)15 [6]  km/s
Other designations
8  Cygni, BD+34° 3590, HD  184171, HIP  96052, HR  7426, SAO  68447.
Database references
SIMBAD data

8 Cygni is a single [7] star in the northern constellation of Cygnus. Based upon its parallax of 3.79 mas, [1] it is approximately 860 light-years (260 parsecs) away from Earth. It is visible to the naked eye as a faint, bluish-white hued star with an apparent visual magnitude of about 4.7. [2] The star is moving closer to the Earth with a heliocentric radial velocity of −21 km/s. [4]

This is an aging subgiant star, as indicated by its spectral type of B3IV. [3] Its effective temperature of 16,100 K fits into the normal range of B-type stars: 11,000 to 25,000 K. 8 Cygni is about twice as hot as the Sun, and it is six times larger and many times brighter in comparison. [5] The elemental abundances are near solar. [8]

Related Research Articles

Upsilon Serpentis, Latinized from υ Serpentis, is a star in the Serpens Caput section of the constellation Serpens. Based upon an annual parallax shift of 13.04 mas as seen from Earth, it is located around 250 light years from the Sun. The star is bright enough to be faintly visible to the naked eye, having an apparent visual magnitude of +5.70. It is a member of the Hyades group, a stream of stars that share a similar trajectory to the Hyades cluster.

<span class="mw-page-title-main">Tau Virginis</span> Star in the constellation Virgo

Tau Virginis is a single star in the zodiac constellation Virgo. With an apparent visual magnitude of 4.28, it is faintly visible to the naked eye. The distance to Tau Virginis, based upon parallax measurements, is approximately 225 light years with a margin of error of ±3 light years.

<span class="mw-page-title-main">Theta Virginis</span> Multiple star system in the constellation of Virgo

Theta Virginis is a multiple star system in the zodiac constellation of Virgo. Based upon parallax measurements, it is about 320 light years from the Sun. The three stars in this system have a combined apparent visual magnitude of 4.37, bright enough to be seen with the naked eye.

<span class="mw-page-title-main">Xi Virginis</span> Star in the constellation Virgo

Xi Virginis is a solitary star in the zodiac constellation of Virgo. It is bright enough to be seen with the naked eye, having an apparent visual magnitude of 4.83. The distance to this star is about 122 light years, as determined from parallax readings.

5 Aquarii is a single star in the zodiac constellation of Aquarius, located about 830 light years away from the Sun, based on parallax. 5 Aquarii is the Flamsteed designation. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 5.55. This object is moving closer to the Earth with a heliocentric radial velocity of −3 km/s.

<span class="mw-page-title-main">Iota Cancri</span> Double star in the constellation Cancer

Iota Cancri is a double star in the constellation Cancer approximately 300 light years from Earth.

<span class="mw-page-title-main">Alpha Chamaeleontis</span> Star in the constellation Chamaleon

Alpha Chamaeleontis, Latinized from α Chamaeleontis, is a solitary star in the southern circumpolar constellation of Chamaeleon. It has an apparent visual magnitude of 4.06 and thus is bright enough to be seen with the naked eye. With an annual parallax shift of 51.12 mas, it is located 63.8 light years from the Sun. The star is drifting closer with a radial velocity of −13 km/s, and is predicted to come to within 47 light-years in 666,000 years.

Pi2 Cygni, Latinized from π2 Cygni, is a triple star system in the northern constellation of Cygnus. It is visible to the naked eye about 2.5° east-northeast of the open cluster M39, having an apparent visual magnitude of 4.24. Based upon an annual parallax shift of 2.95 mas, it is located at a distance of roughly 1,100 light years from the Sun.

<span class="mw-page-title-main">Kappa Lyrae</span> Star in the constellation Lyra

κ Lyrae, Latinized as Kappa Lyrae, is a solitary star in the northern constellation of Lyra, near the constellation border with Hercules. It is visible to the naked eye as a faint, orange-hued point of light with an apparent visual magnitude of 4.33. This object is located approximately 252 light years from the Sun based on parallax, but is moving closer with a radial velocity of −24 km/s.

<span class="mw-page-title-main">52 Cygni</span> Binary star system in the constellation Cygnus

52 Cygni is a giant star in the northern constellation of Cygnus with an apparent magnitude of 4.22. Based on its Hipparcos parallax, it is about 291 light-years (89 pc) away.

HD 180262 is a wide double star in the equatorial constellation of Aquila. The pair have an angular separation of 89.823″.

HD 126128/9 is a triple star in the northern constellation of Boötes. Two of the components form a binary star system with an orbital period of 39.5 years and an eccentricity of 0.25. The third component, and the brightest member of the trio, lies at an angular separation of 6.250″ from the other two.

ψ Cygni, Latinised as Psi Cygni, is a triple star system in the constellation called Cygnus. With a combined apparent visual magnitude of 4.92, it is visible to the naked eye. As of 2002, the inner pair, components Aa and Ab, had an angular separation of 0.10 arc seconds along a position angle of 77.6°. Their combined visual magnitude is 5.05. Relative to this pair, the third member of the system, magnitude 7.61 component B, had an angular separation of 2.87 arc seconds along a position angle of 175.6° as of 2010. Based upon an annual parallax shift of 11.59 mas, Psi Cygni is located around 281 light years from the Sun.

Omega<sup>1</sup> Cygni B-type subgiant star in the constellation Cygnus

Omega1 Cygni, Latinized from ω1 Cygni, is the Bayer designation for a solitary star in the northern constellation of Cygnus. It is visible to the naked eye with an apparent visual magnitude of 4.94. Based upon an annual parallax shift of 2.59 mas, it is estimated to lie roughly 1,260 light years from the Sun. Relative to its neighbors, this star has a peculiar velocity of 25.7±2.2 km/s.

<span class="mw-page-title-main">30 Cygni</span> Star in the constellation Cygnus

30 Cygni is a class A5III star in the constellation Cygnus. Its apparent magnitude is 4.83 and it is approximately 610 light years away based on parallax.

<span class="mw-page-title-main">Epsilon Crateris</span> Solitary star in the constellation Crater

Epsilon Crateris is a solitary star in the southern constellation of Crater. Visible to the naked eye, it has an apparent visual magnitude of 4.84. It is located in the sky above Beta Crateris, and slightly to the left, or east, marking the lower right edge of the rim of the bowl and is somewhat closer to Theta Crateris, which is further east at the top of the bowl. With an annual parallax shift of 8.67 mas as seen from the Earth, its estimated distance is around 376 light years from the Sun.

Upsilon<sup>4</sup> Eridani Star in the constellation Eridanus

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.

Upsilon2 Hydrae, Latinised from υ2 Hydrae, is a solitary star in the equatorial constellation of Hydra. Visible to the naked eye, it is photometrically stable with an apparent visual magnitude of 4.59. Based upon an annual parallax shift of 10.40 mas as seen from Earth, it is located about 314 light-years from the Sun.

Tau2 Hydrae is a probable astrometric binary star system in the equatorial constellation of Hydra. Based upon an annual parallax shift of 6.30 mas as seen from Earth, it is located around 520 light years from the Sun. The brighter component is visible to the naked eye with an apparent visual magnitude of +4.56.

26 Ursae Majoris is a single star in the northern circumpolar constellation of Ursa Major, located 262 light years away from the Sun. It is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.47. The object is moving further from the Earth with a heliocentric radial velocity of +22 km/s.

References

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