HR 6801

Last updated
HR 6801
Sagittarius constellation map.svg
Red circle.svg
Location of HR 6801 (circled)
Observation data
Epoch J2000       Equinox J2000
Constellation Sagittarius
Right ascension 18h 11m 43.33342s [1]
Declination −23° 42 04.4346 [1]
Apparent magnitude  (V)4.96 [2]
Characteristics
Spectral type K0III [3]
U−B color index +0.90 [4]
B−V color index +1.05 [4]
Astrometry
Radial velocity (Rv)+5.71±0.20 [1]  km/s
Proper motion (μ)RA: +9.337 [1]   mas/yr
Dec.: −31.999 [1]   mas/yr
Parallax (π)12.6303 ± 0.2449  mas [1]
Distance 258 ± 5  ly
(79 ± 2  pc)
Absolute magnitude  (MV)0.49 [2]
Details
Mass 2.24 [5]   M
Radius 13.35+0.14
−0.92
[1]   R
Luminosity 78.6±1.7 [1]   L
Surface gravity (log g)2.65 [5]   cgs
Temperature 4,705+171
−25
[1]   K
Metallicity [Fe/H]0.00 [5]   dex
Rotational velocity (v sin i)1.6 [6]  km/s
Other designations
11 Sgr, CD–23°14047, GC  24799, HD  166464, HIP  89153, HR  6801, SAO  186437, CCDM J18117-2342A, WDS J18117-2342A [7]
Database references
SIMBAD data

HR 6801 is a single [8] star in the southern zodiac constellation of Sagittarius. It was designated as 1 Sagittarii by Flamsteed, but is now often referred to as 11 Sagittarii. Flamsteed's 11 Sgr actually refers to a different, much fainter star. [9] The object is orange in hue and is visible to the naked eye as a faint point of light with an apparent visual magnitude of 4.96. [2] The distance to this star is approximately 258  light years based on stellar parallax, and it is drifting further away with a radial velocity of +6 km/s. [1]

This is an aging giant star with a stellar classification of K0III. [10] It is a red clump giant, [11] which indicates it is on the horizontal branch and is generating energy through helium fusion at its core. The star has 2.24 [5] times the mass of the Sun and has expanded to 13.4 times the Sun's radius. It is radiating 79 times the luminosity of the Sun from its photosphere at an effective temperature of 4,705 K. [1]

A faint visual companion, component B, has magnitude 11.51 and an angular separation of 43.7 . [12]

Related Research Articles

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ο Sagittarii, Latinized as Omicron Sagittarii, is a single star in the constellation Sagittarius. It is yellow in hue and visible to the naked eye with an apparent visual magnitude of +3.77. The distance to this star is approximately 142 light years based on parallax. It is drifting further away from the Sun with a radial velocity of +26 km/s, having come to within 86 ly around a million years ago.

Rho<sup>1</sup> Sagittarii Star in the constellation Sagittarius

Rho1 Sagittarii, Latinized from ρ1 Sagittarii, is a single, variable star in the southern constellation of Sagittarius. It has a white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around 3.93. The distance to this star is approximately 127 light years based on parallax, and it is drifting further away with a radial velocity of +1.2 km/s. It is positioned near the ecliptic and so it can be occulted by the Moon.

<span class="mw-page-title-main">59 Sagittarii</span> Star in the constellation Sagittarius

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<span class="mw-page-title-main">60 Sagittarii</span> Possible binary star system in the constellation Sagittarius

60 Sagittarii is a suspected binary star system in the southern constellation of Sagittarius. It has the Bayer designation A Sagittarii, while 60 Sagittarii is the Flamsteed designation. This naked-eye object forms the northwest corner of the asterism called the Terebellum and, with an apparent magnitude of approximately 4.84, it is the dimmest of the four stars in the Terebellum. It is located 379 light-years from the Sun, based on parallax, but is moving closer with a radial velocity of −51 km/s.

<span class="mw-page-title-main">Epsilon Scuti</span> Star in the constellation Scutum

Epsilon Scuti, Latinized from ε Scuti, is a probable astrometric binary star system in the constellation Scutum. It is faintly visible to the naked eye with an apparent visual magnitude of +4.88. Based upon an annual parallax shift of 5.71 mas as seen from Earth,> it is located approximately 570 light years from the Sun. It is moving closer to the Sun with a radial velocity of −9.8 km/s. Epsilon Scuti was a latter designation of 3 Aquilae.

<span class="mw-page-title-main">8 Andromedae</span> Mulitple star system in the constellation Andromeda

8 Andromedae, abbreviated 8 And, is a probable triple star system in the northern constellation of Andromeda. 8 Andromedae is the Flamsteed designation. It is visible to the naked eye with an apparent visual magnitude of 4.82. Based upon an annual parallax shift of 5.7 mas, it is located about 570 light years from the Earth. It is moving closer with a heliocentric radial velocity of −8 km/s.

<span class="mw-page-title-main">1 Aurigae</span> Star in the constellation Perseus

1 Aurigae is the original name for a star now in the constellation Perseus. It was the first entry in John Flamsteed's catalogue of stars in Auriga. When Eugène Joseph Delporte drew up simplified boundaries for the constellations on behalf of the International Astronomical Union in 1930, 1 Aurigae ended up over the border in Perseus. To avoid confusion, the star may instead be referred to by its Harvard Revised catalogue number, HR 1533.

<span class="mw-page-title-main">15 Vulpeculae</span> Star in the constellation Vulpecula

15 Vulpeculae is a variable star in the northern constellation of Vulpecula, located approximately 243 light years away based on parallax. It has the variable star designation NT Vulpeculae; 15 Vulpeculae is the Flamsteed designation. It is visible to the naked eye as a faint, white-hued star with a typical apparent visual magnitude of 4.66. This object is moving closer to the Earth with a heliocentric radial velocity of −26 km/s.

<span class="mw-page-title-main">4 Sagittarii</span> Astrometric binary star in the constellation Sagittarius

4 Sagittarii is a suspected astrometric binary star system in the zodiac constellation of Sagittarius, located approximately 390 light years away based on parallax. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.74, The system is moving closer to the Earth with a heliocentric radial velocity of −18 km/s.

<span class="mw-page-title-main">10 Leonis Minoris</span> Star in the constellation Leo Minor

10 Leonis Minoris is a single variable star in the northern constellation Leo Minor, located approximately 191 light years away based on parallax. It has the variable star designation SU Leonis Minoris; 10 Leonis Minoris is the Flamsteed designation. This body is visible to the naked eye as a faint, orange-hued star with a baseline apparent visual magnitude of 4.54. It is moving closer to the Earth with a heliocentric radial velocity of −12 km/s.

<span class="mw-page-title-main">20 Monocerotis</span> Star in the constellation Monoceros

20 Monocerotis is a single star located about 194 light years away from the Sun in the equatorial constellation of Monoceros. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.92. The star is receding from the Earth with a heliocentric radial velocity of +78 km/s.

<span class="mw-page-title-main">24 Scorpii</span> Star in the constellation Ophiuchus

24 Scorpii is a star that was originally placed by John Flamsteed within the constellation of Scorpius but in now placed within the southeastern constellation of Ophiuchus. It is visible to the naked eye as a faint, yellow-hued point of light with an apparent visual magnitude of 4.91. Based on the trigonometric parallax published in Gaia Data Release 2, the star lies approximately 121 parsecs or 390 light years away. It is positioned near the ecliptic and thus is subject to lunar occultations.

<span class="mw-page-title-main">31 Orionis</span> Binary star in the constellation Orion

31 Orionis is a binary star system in the equatorial constellation of Orion, located near the bright star Mintaka. It is visible to the naked eye as a faint, orange-hued point of light with a baseline apparent visual magnitude of 4.71. The distance to this system is approximately 490 light years away based on parallax, and it is drifting further away with a mean radial velocity of +6 km/s.

<span class="mw-page-title-main">54 Persei</span> Star in the constellation Perseus

54 Persei is a single star in the northern constellation of Perseus. It is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of 4.93. The star is located approximately 220 light years away based on parallax, but is drifting closer with a radial velocity of −27 km/s.

<span class="mw-page-title-main">HD 61772</span> Star in the constellation Puppis

HD 61772 is a bright giant star in the constellation Puppis. Its apparent magnitude is 4.98 and it is approximately 660 light years away based on parallax.

<span class="mw-page-title-main">21 Sagittarii</span> Binary star system in the constellation Sagittarius

21 Sagittarii is a binary star system in the southern zodiac constellation of Sagittarius. It is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.81. The system is located approximately 410 light years away from the Sun based on parallax. It is moving closer to the Earth with a heliocentric radial velocity of −11.80 km/s.

56 Sagittarii is a single star in the southern constellation of Sagittarius. It has the Bayer designation f Sagittarii, while 56 Sagittarii is the Flamsteed designation. This object is visible to the naked eye as a faint, orange-hued point of light with an apparent visual magnitude of 4.87. It is located approximately 208 light years away from the Sun based on parallax, and is drifting further away with a radial velocity of +22 km/s.

<span class="mw-page-title-main">43 Sagittarii</span> Star in the constellation of Sagittarius

43 Sagittarii is a single star in the southern constellation of Sagittarius. It has the Bayer designation d Sagittarii, while 43 Sagittarii is the Flamsteed designation. This object is visible to the naked eye as a faint, yellow-hued star with an apparent visual magnitude of 4.88. From parallax measurements, it is estimated to lie around 470 light years away from the Sun. The star is drifting further from the Earth with a heliocentric radial velocity of +15.2 km/s. It is located near the ecliptic and thus is subject to lunar occultations.

<span class="mw-page-title-main">9 Persei</span> Blue supergiant star in the constellation Perseus

9 Persei is a single variable star in the northern constellation Perseus, located around 4,300 light years away from the Sun. It has the Bayer designation i Persei; 9 Persei is the Flamsteed designation. This body is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of about 5.2. It is moving closer to the Sun with a heliocentric radial velocity of −15.2 km/s. The star is a member of the Perseus OB1 association of co-moving stars.

<span class="mw-page-title-main">21 Persei</span> Star in the constellation Perseus

21 Persei is a single, variable star in the northern constellation of Perseus, located about 331 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 5.10 km/s. The object is moving further from the Earth with a heliocentric radial velocity of +8.5 km/s. It has the variable star designation LT Persei; 21 Persei is the Flamsteed designation.

References

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