69 Herculis

Last updated
69 Herculis
Observation data
Epoch J2000       Equinox J2000
Constellation Hercules
Right ascension 17h 17m 40.25427s [1]
Declination +37° 17 29.3995 [1]
Apparent magnitude  (V)4.63 (4.66 + 8.68) [2]
Characteristics
Evolutionary stage main sequence
Spectral type A2V [3]
B−V color index 0.043±0.003 [4]
Astrometry
Radial velocity (Rv)−9.90±1.78 [5]  km/s
Proper motion (μ)RA: −43.05 [1]   mas/yr
Dec.: +64.36 [1]   mas/yr
Parallax (π)18.59 ± 0.33 [1]   mas
Distance 175 ± 3  ly
(53.8 ± 1.0  pc)
Absolute magnitude  (MV)0.99 [4]
Details
69 Her A
Mass 2.12 [6]   M
Radius 2.2 [7]   R
Luminosity 36.64 [4]   L
Surface gravity (log g)4.02 [8]   cgs
Temperature 9,141 [8]   K
Metallicity [Fe/H]0.29 [8]   dex
Rotational velocity (v sin i)141 [8]  km/s
Age 155 [9]   Myr
Other designations
e Her, 69 Her, BD+37°2864, HD  156729, HIP  84606, HR  6436, SAO  65921 [10]
Database references
SIMBAD data

69 Herculis is a binary star [2] system in the northern constellation Hercules. It has the Bayer designation e Herculis, while 69 Herculis is the Flamsteed designation. This object is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 4.63. [2] The distance to this system can be estimated from parallax measurements, which yields a range of 175  light years. It is moving closer to the Earth with a heliocentric radial velocity of −10 km/s. [5]

The magnitude 4.66 [2] primary, designated component A, is an A-type main-sequence star with a stellar classification of A2V. [3] It is 155 [9]  million years old with 2.12 [6] times the mass of the Sun. The star is spinning with a projected rotational velocity of 155 km/s, which is creating an equatorial bulge that is 5% larger than the star's polar radius. [9] It is about 2.2 [7] times the size of the Sun and is radiating 37 [4] times the Sun's luminosity from its photosphere at an effective temperature of 9,141 K. [8]

The secondary, component B, is magnitude 8.68 star with an angular separation of 0.840 from the primary, as of 2008. [2] X-ray emission has been detected from this system. As A-type stars are not expected to be X-ray sources, this emission is most likely coming from the companion. [11]

Related Research Articles

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Gamma Trianguli Australis Star in the constellation Triangulum Australe

Gamma Trianguli Australis is a single, white-hued star in the southern constellation of Triangulum Australe. Along with Alpha and Beta Trianguli Australis it forms a prominent triangular asterism that gives the constellation its name. It is the third-brightest member of this constellation with an apparent visual magnitude of +2.87. based upon parallax measurements, Gamma Trianguli Australis is located at a distance of about 184 light-years from Earth.

Tau Virginis

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.

23 Andromedae, abbreviated 23 And, is a presumed single star in the constellation Andromeda, although it has been a suspected spectroscopic binary. 23 Andromedae is the Flamsteed designation. Its apparent visual magnitude is 5.71, which indicates it is dimly visible to the naked eye under good viewing conditions. The distance to 23 And, as determined from its annual parallax shift of 26.8 mas, is 121.6 light years. The star is moving further from the Earth with a heliocentric radial velocity of −27 km/s. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.191″ per year.

Chi Boötis, Latinized as χ Boötis, is a single, white-hued star in the northern constellation Boötes, near the eastern constellation border with Corona Borealis. It is faintly visible to the naked eye with an apparent visual magnitude of +5.3. Based upon an annual parallax shift of 13.0 mas as seen from the Earth, it is located about 251 light years from the Sun. The star is moving closer to the Sun with a radial velocity of −16 km/s.

HD 42818 is a suspected astrometric binary star system in the northern circumpolar constellation of Camelopardalis. It is visible to the naked eye with an apparent visual magnitude of +4.76. Based upon an annual parallax shift of 18.64±0.23 mas as seen from Earth's orbit, it is located some 175 light years away. The system appears to be moving closer with a heliocentric radial velocity of −7 km/s. As of 2012, it is estimated that the system will make its closest approach to the Sun in 485,000 years at a distance of around 169.2 ly (51.87 pc).

Pi Cassiopeiae Variable star in the constellation Cassiopeia

Pi Cassiopeiae, Latinized from π Cassiopeiae, is a close binary star system in the constellation Cassiopeia. It is visible to the naked eye with an apparent visual magnitude of +4.949. Based upon an annual parallax shift of 18.63 mas as seen from Earth, this system is located about 175 light years from the Sun.

π2 Columbae, Latinized as Pi2 Columbae, is a binary star system in the southern constellation of Columba, near the southern constellation border with Pictor. It is white-hued and dimly visible to the naked eye with a combined apparent visual magnitude of 5.50. Based upon an annual parallax shift of 12.8 mas as seen from Earth, this system is located about 254 light years from the Sun. They are receding with a heliocentric radial velocity of +31 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.

Tau Herculis Variable star in the constellation Hercules

Tau Herculis, a name Latinized from τ Herculis, is a variable star in the northern constellation of Hercules. It has a blue-white hue and is visible to the naked eye at night with an apparent visual magnitude that fluctuates around 3.91. The star is located at a distance of approximately 307 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −16 km/s.

Gamma Crateris Star in the constellation Crater

Gamma Crateris is a binary star system, divisible with a small amateur telescope, and located at the center of the southern constellation of Crater. It is visible to the naked eye with an apparent visual magnitude of 4.06. With an annual parallax shift of 39.62 mas as seen from Earth, this star is located 82.3 light years from the Sun. Based upon the motion of this system through space, it is a potential member of the Castor Moving Group.

Mu Piscis Austrini Star in the constellation Piscis Austrinus

Mu Piscis Austrini is a solitary, white-hued star in the southern constellation of Piscis Austrinus. It is visible to the naked eye with an apparent visual magnitude of +4.49. Based upon an annual parallax shift of 26.7542 mas as seen from the Gaia space telescope, the star is located around 122 ± 2 light years from the Sun.

Rho Piscium Star in the constellation Pisces

Rho Piscium is a solitary, yellow-hued star in the zodiac constellation of Pisces. With an apparent visual magnitude of +5.34, it is faintly visible to the naked eye. Based upon an annual parallax shift of 39.66 mas as seen from Earth, it is located 82 light years from the Sun. It is a member of the thin disk population of the Milky Way.

Psi<sup>2</sup> Piscium Star in the constellation Pisces

Psi2 Piscium (ψ2 Piscium) is a white-hued star in the zodiac constellation of Pisces. It is faintly visible to the naked eye, having an apparent visual magnitude of +5.56. Based upon an annual parallax shift of 8.66 mas as seen from Earth, it is located about 380 light years from the Sun. It has a peculiar velocity of 14.6±2.9 km/s, indicating it is a runaway star.

HD 16754 is a binary or triple-star system in the constellation Eridanus. It has the Bayer designation s Eridani; HD 16754 is the designation from the Henry Draper catalogue. The system is visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.74. It is located at a distance of approximately 132 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +18 km/s. The system is a member of the Columba association of co-moving stars.

64 Eridani is a single, yellow-white hued star in the constellation Eridanus having variable star designation S Eridani. It is faintly visible to the naked eye with an apparent visual magnitude of 4.77. The annual parallax shift is measured at 12.01 mas, which equates to a distance of about 272 light years. In addition to its proper motion, it is moving closer to the Sun with a radial velocity of around −9 km/s.

30 Monocerotis is a single star in the equatorial constellation of Hydra, located 122 light years away from the Sun. It has the Bayer designation C Hydrae; 30 Monocerotis is the Flamsteed designation and was assigned when it belonged to the Monoceros constellation. The object is visible to the naked eye as a white-hued star with an apparent visual magnitude of 3.90. It is moving away from the Earth with a heliocentric radial velocity of +10 km/s.

74 Cygni is a visual binary star system in the northern constellation Cygnus, located around 249 light years distant from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.04. The pair orbit each other with a period of 1.57 years and an eccentricity of 0.5. The system is a source of X-ray emission, which is most likely coming from the secondary component.

Sigma1 Gruis, a Latinization of σ1 Gruis, is a star in the constellation Grus. It is a dim, white-hued star near the lower limit for visibility to the naked eye with an apparent visual magnitude of 6.26. This object is located 229 light-years (70.1 pc) distant from the Sun based on parallax. The radial velocity of this star is poorly constrained, but it appears to be drifting further away at the rate of +7 km/s.

μ Fornacis is the Bayer designation for a star in the southern constellation of Fornax. With an apparent visual magnitude of 5.27, it is visible to the naked eye. The distance to this star, as determined by its annual parallax shift of 10.18 mas, is around 320 light years.

References

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