18 Boötis

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18 Boötis
Observation data
Epoch J2000       Equinox J2000
Constellation Boötes
Right ascension 14h 19m 16.27966s [1]
Declination +13° 00 15.4859 [1]
Apparent magnitude  (V)5.41 [2]
Characteristics
Spectral type F3 V [3]
B−V color index 0.385±0.011 [2]
Astrometry
Radial velocity (Rv)−0.40±0.7 [2]  km/s
Proper motion (μ)RA: +105.273 [1]   mas/yr
Dec.: −31.389 [1]   mas/yr
Parallax (π)38.1262 ± 0.1323  mas [1]
Distance 85.5 ± 0.3  ly
(26.23 ± 0.09  pc)
Absolute magnitude  (MV)3.33 [2]
Details
Mass 1.31 [4]   M
Radius 1.4 [5]   R
Luminosity 3.90 [2]   L
Surface gravity (log g)4.30 [4]   cgs
Temperature 6,731±229 [4]   K
Metallicity [Fe/H]−0.03±0.04 [6]   dex
Rotational velocity (v sin i)40.5±2.0 [7]  km/s
Age 1.154 [4]   Gyr
Other designations
18 Boo, BD+13°2782, FK5  1372, GJ  3841, HD  125451, HIP  69989, HR  5365, SAO  100975, WDS J14193+1300 [8]
Database references
SIMBAD data

18 Boötis is a single [9] star in the northern constellation of Boötes, [8] located about 85 light years away from the Sun. [1] It is visible to the naked eye as a faint, yellow-white hued star with an apparent visual magnitude of 5.41. [2] This object is a suspected member of the Ursa Major Moving Group, based on velocity criteria. [10] It has a magnitude 10.84 optical companion at an angular separation of 163.7 along a position angle of 219°, as of 2010. [11]

This is an F-type main-sequence star with a stellar classification of F3 V. [3] Older surveys gave a class of F5 IV, [12] showing the luminosity class of a subgiant star. It shows strong evidence for short-term chromospheric variability, although it is not optically variable. [13]

18 Boötis is an estimated 1.15 [4]  billion years old and is spinning with a projected rotational velocity of 40.5 km/s. [7] It has 1.3 [4] times the mass of the Sun and 1.4 [5] times the Sun's radius. The star is radiating 3.9 [2] times the luminosity of the Sun from its photosphere at an effective temperature of 6,731 K. [4] An infrared excess has been detected that suggests a cold debris disk is orbiting 34.9  AU from the host star with a blackbody temperature fit of 65 K. [5]

Related Research Articles

Ross 248, also called HH Andromedae or Gliese 905, is a small star approximately 10.30 light-years from Earth in the northern constellation of Andromeda. Despite its proximity it is too dim to be seen with the naked eye. It was first catalogued by Frank Elmore Ross in 1926 with his second list of proper-motion stars; on which count it ranks 261st in the SIMBAD database. It was too dim to be included in the Hipparcos survey. In about 40,000 years, Voyager 2 will pass 1.7 light-years from the star.

<span class="mw-page-title-main">Nu Tauri</span> Star in the constellation Taurus

ν Tauri, Latinized as Nu Tauri, is a single star in the zodiac constellation of Taurus. It is a white-hued star and is visible to the naked eye with an apparent visual magnitude of +3.91. This object is located 117 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −6 km/s. It is predicted to come to within roughly 18.4 ly of the Sun in around five million years.

Mu Telescopii, Latinized from μ Telescopii is a solitary star in the southern constellation Telescopium. It has an apparent visual magnitude of 6.28, placing it near the limit of naked eye visibility. The object is relatively close at a distance of 118 light years but is receding with a heliocentric radial velocity of 8.6 km/s.

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.

<span class="mw-page-title-main">Theta Boötis</span> Star in the northern constellation of Boötes

Theta Boötis, Latinized from θ Boötis, is a star in the northern constellation of Boötes the herdsman, forming a corner of the upraised left hand of this asterism. It has the traditional name Asellus Primus and the Flamsteed designation 23 Boötis. Faintly visible to the naked eye, this star has a yellow-white hue with an apparent visual magnitude of 4.05. It is located at a distance of 47.2 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −10.6 km/s.

<span class="mw-page-title-main">Sigma Boötis</span> Star in the constellation Boötes

Sigma Boötis, its name Latinized from σ Boötis, is a single star in the northern constellation of Boötes. It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude of 4.46. Located to the southeast of Rho Boötis, the dwarf Sigma may at first appear as a naked-eye double, but the angular proximity with Rho is merely line-of-sight. Sigma Boötis is located at a distance of 51.1 light years from the Sun based on parallax. The star has a relatively high proper motion and is traversing the sky at the rate of 0.230″ yr−1.

Chi Boötis, Latinised 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.

26 Boötis is a single star in the northern constellation of Boötes, located 188 light years away from the Sun. It is visible to the naked eye as a dim, yellow-white hued star with an apparent visual magnitude of 5.91. This object is moving closer to the Earth with a heliocentric radial velocity of −16.5 km/s.

40 Boötis is a single star located 166.5 light years away from the Sun in the northern constellation of Boötes. It is visible to the naked eye as a dim, yellow-white hued star with an apparent visual magnitude of 5.64. The star is moving away from the Earth with a heliocentric radial velocity of +12 km/s.

<span class="mw-page-title-main">38 Lyncis</span> Star in the constellation Lynx

38 Lyncis is a multiple star system in the northern constellation of Lynx. It located about 125 light-years from the Sun, based on parallax.

HD 88955 is a single, white-hued star in the southern constellation of Vela. It can be viewed with the naked eye, having an apparent visual magnitude of 3.85. The distance to HD 88955 can be determined from its annual parallax shift of 32.7 mas, which yields a separation of 100 light years from the Sun. It is moving further from the Earth with a heliocentric radial velocity of +7 km/s. Bayesian analysis suggests HD 88955 is a member of the Argus Association, a group of co-moving stars usually associated with the IC 2391 open cluster.

HD 86264 is a single star with an exoplanetary companion in the equatorial constellation of Hydra. It is too faint to be readily visible to the naked eye with an apparent visual magnitude of 7.41. The distance to this star, as determined by parallax measurements, is 219 light-years, and it is drifting further away with a radial velocity of +7.4 km/s. A 2015 survey ruled out the existence of any stellar companions at projected distances above 30 astronomical units.

<span class="mw-page-title-main">CL Draconis</span> Star in the constellation Draco

CL Draconis is a single star in the northern circumpolar constellation of Draco. It can be viewed with the naked eye, having an apparent visual magnitude of 4.96. The distance to this star, as determined from its annual parallax shift of 29.9 mas, is 109 light years. It is moving closer to the Earth with a heliocentric radial velocity of −11 km/s. The star has a relatively high proper motion, traversing the celestial sphere at the rate of 0.185″/yr.

38 Geminorum is a binary star system in the northern zodiac constellation of Gemini. It has the Bayer designation e Geminorum, while 38 Geminorum is the Flamsteed designation. This system is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.71. The primary component is a magnitude 4.75 star, while the secondary is magnitude 7.80. The system is located about 98 light years away from the Sun based on parallax, and is drifting further away with a radial velocity of +16 km/s. It is a potential member of the Tucana–Horologium stellar kinematic group.

HD 202628 is a single star in the southern constellation of Microscopium. It has an apparent visual magnitude of +6.7, which makes it too faint to be readily visible to the naked eye. The star is located at a distance of 77.7 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +12.1 km/s. The absolute magnitude of this star is 4.86.

56 Persei is at least a triple star and possibly a quadruple star system in the northern constellation of Perseus. It is visible to the naked eye as a dim point of light with a combined apparent visual magnitude of 5.77. The system is located 139 light-years (42.5 pc) distant from the Sun based on parallax, but is drifting closer with a radial velocity of −32 km/s.

<span class="mw-page-title-main">TU Corvi</span> Star in the constellation Corvus

TU Corvi is a yellow-white hued star in the southern constellation of Corvus. It is a dimly visible to the naked eye with an apparent visual magnitude of 6.20. The distance to this star can be estimated from its annual parallax shift of 13.3 mas, yielding a range of about 246 light years. Based upon measured changes in its proper motion, it may be a close binary system.

<span class="mw-page-title-main">32 Tauri</span> Yellow-white hued subgiant star in the constellation Taurus.

32 Tauri is the Flamsteed designation for a solitary star in the zodiac constellation of Taurus. It has a visual magnitude of 5.64, making it visible to the naked eye from suburban skies. The position of this star near the ecliptic plane means that it is subject to occultations by the Moon. Parallax measurements put it at a distance of 144 light years from the Sun. It is drifting further away with a radial velocity of +31.9 km/s, having come to within 88.9 light-years some 759,000 years ago.

<span class="mw-page-title-main">HD 111395</span> Star in the constellation Coma Berenices

HD 111395 is a single, variable star in the northern constellation of Coma Berenices. It has the variable star designation LW Com, short for LW Comae Berenices; HD 111395 is the Henry Draper Catalogue designation. The star has a yellow hue and is just bright enough to be barely visible to the naked eye with an apparent visual magnitude that fluctuates around 6.29. Based upon parallax measurements, it is located at a distance of 55.8 light years from the Sun. The star is drifting closer with a radial velocity of −8.9 km/s. It is a member of the Eta Chamaeleontis stellar kinematic group.

HD 46588 is a star in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.44, allowing it to be faintly seen with the naked eye. The object is relatively close at a distance of only 59 light years but is receding with a heliocentric radial velocity of 15 km/s.

References

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