HD 170521

Last updated
HD 170521
Corona Australis constellation map.svg
Red circle.svg
Location of HD 170521 (circled)
Observation data
Epoch J2000.0        Equinox J2000.0 (ICRS)
Constellation Corona Australis
Right ascension 18h 31m 56.22382s [1]
Declination −43° 30 26.5714 [1]
Apparent magnitude  (V)5.69±0.01 [2]
Characteristics
Spectral type K2 III [3]
B−V color index +1.34 [4]
Astrometry
Radial velocity (Rv)7.2±0.4 [5]  km/s
Proper motion (μ)RA: −1.328  mas/yr [1]
Dec.: −8.795  mas/yr [1]
Parallax (π)2.1538 ± 0.1596  mas [1]
Distance 1,500 ± 100  ly
(460 ± 30  pc)
Absolute magnitude  (MV)−1.90 [6]
Details
Mass 1.55 [7]   M
Radius 78.6±4.1 [8]   R
Luminosity 934 [9]   L
Surface gravity (log g)0.96 [10]   cgs
Temperature 4,474±122 [11]   K
Metallicity [Fe/H]−0.49 [7]   dex
Rotational velocity (v sin i)6.5±1 [12]  km/s
Other designations
12 G. Coronae Australis [13] , CD−43°12600, CPD−34°8647, GC  25272, HD  170521, HIP  90842, HR  6937, SAO  229094 [14]
Database references
SIMBAD data

HD 170521, also known as HR 6937 or rarely 12 G. Coronae Australis, is a solitary star [15] located in the southern constellation Corona Australis. It is faintly visible to the naked eye as an orange-hued point of light with an apparent magnitude of 5.69. [2] The object is located relatively far at a distance of approximately 1,500 light years based on Gaia DR3 parallax measurements, [1] and it is receding with a heliocentric radial velocity of 7.2  km/s . [5] At its current distance, HD 170521's brightness is heavily diminished by 0.46 magnitudes due to extinction from interstellar dust [16] and it has an absolute magnitude of −1.90. [6]

HD 170521 has a stellar classification of K2 III, [3] indicating that it is an evolved red giant. It has 1.55 times the mass of the Sun [7] but it has expanded to 78.6 times the Sun's radius. [8] The object radiates 934 times the luminosity of the Sun [9] from its enlarged photosphere at an effective temperature of 4,474  K . [11] HD 170521 is metal deficient with an iron abundance only 32.4% that of the Sun (Fe/H) = −0.49 [7] and it spins modestly with a projected rotational velocity of 6.5  km/s . [12]

Related Research Articles

<span class="mw-page-title-main">Iota Telescopii</span> K-type giant; Telescopium

ι Telescopii, Latinized as Iota Telescopii and abbreviated Iota Tel, is a solitary star located in the southern constellation Telescopium. It is faintly visible to the naked eye as an orange-hued star with an apparent visual magnitude of +4.88. The star is located roughly 377 light years distant from the Solar System based on Gaia DR3 parallax measurements and it is receding with a radial velocity of 22.3 km/s. At its current distance, Iota Tel's brightness is diminished by 0.19 magnitudes due to interstellar dust and it has an absolute magnitude of −0.39.

<span class="mw-page-title-main">HD 27245</span> Star in the constellation Camelopardalis

HD 27245, also known as HR 1335 or rarely 25 H. Camelopardalis is a solitary red-hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.4, making it faintly visible to the naked eye. Gaia DR3 Parallax measurements place it approximately 607 light years away from it the Solar System and is drifting further away with a heliocentric radial velocity of 25.2 km/s. At its current distance, HD 27245's brightness is diminished by 0.36 magnitudes due to extinction from interstellar dust. It has an absolute magnitude of −0.27.

HD 27274, also known as Gliese 167, is a solitary, orange hued star located in the southern constellation Dorado. It has an apparent magnitude of 7.63, making it readily visible in binoculars, but not to the naked eye. Based on parallax measurements from the Gaia spacecraft, the star is known to be located 42.5 light-years away from the Solar System However, it is drifting closer with a heliocentric radial velocity of −23 km/s. At its current distance, HD 27274 is dimmed down by 0.05 magnitudes due to interstellar dust.

<span class="mw-page-title-main">HD 24479</span> Star in the constellation Camelopardalis

HD 24479, also designated as HR 1204, is a solitary, bluish-white hued star located in the northern circumpolar constellation Camelopardalis. The star is visible to the naked eye with an apparent visual magnitude of 5.04. Based on Gaia DR3 parallax measurements, it is located 385 light years from the Sun. However, it is receding with a somewhat constrained heliocentric radial velocity of 4.6 km/s. At its current distance, HD 24479's brightness is diminished by 0.29 magnitudes due to interstellar dust.

<span class="mw-page-title-main">S Apodis</span> Variable star in the constellation Apus

S Apodis, also known as HD 133444 is a variable star located in the southern circumpolar constellation Apus. It has an apparent magnitude ranging from 9.6 to 17, which is below the limit for naked eye visibility. The object is located relatively far at a distance of approximately 15,000 light years based on Gaia DR3 parallax measurements, but it is drifting closer with a heliocentric radial velocity of −75 km/s.

HD 121439, also known as HR 5240, is a solitary, bluish-white hued star located in the southern circumpolar constellation Apus. It has an apparent magnitude of 6.08, allowing it to be faintly visible to the naked eye. The object is located relatively far at a distance of 774 light years based on Gaia DR3 parallax measurements but is receding with a fairly constrained radial velocity of 4 km/s. At its current distance, HD 121439's brightness is diminished by 0.57 magnitudes due to interstellar dust.

<span class="mw-page-title-main">HD 57197</span> Star in the constellation Puppis

HD 57197, also known as M Puppis or HR 2789, is a suspected astrometric binary located in the southern constellation Puppis, the poop deck. It has an apparent magnitude of 5.84, making it faintly visible to the naked eye under ideal conditions. Based on parallax measurements from the Gaia satellite, the system is estimated to be 629 light years away from the Solar System. The value is poorly constrained, but it appears to be receding with a heliocentric radial velocity of 13 km/s. At its current distance, HD 57197's brightness is diminished by 0.3 magnitudes due to interstellar dust. It has an absolute magnitude of -0.43.

<span class="mw-page-title-main">HD 26764</span> Star in the constellation Camelopardalis

HD 26764, also known as HR 1314 or rarely 14 H. Camelopardalis, is a solitary white hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.19, making it faintly to the naked eye if viewed under good conditions. Gaia DR3 parallax measurements place the object at a distance of 266 light years and is drifting closer with a poorly constrained heliocentric radial velocity of 3 km/s. At its current distance, HD 26764's brightness is diminished by 0.26 magnitudes due to interstellar dust.

<span class="mw-page-title-main">HD 76236</span> Star in the constellation Chamaeleon

HD 76236, also designated as HR 3543 or rarely 11 G. Chamaeleontis, is a solitary star located in the southern circumpolar constellation Chamaeleon. It is faintly visible to the naked eye as an orange-hued star with an apparent magnitude of 5.77. Based on parallax measurements from the Gaia satellite, the object is estimated to be 612 light years away. Currently, it is receding with a heliocentric radial velocity of 7 km/s. At its current distance, HD 76236's brightness is diminished by 0.39 magnitudes due to interstellar dust. It has an absolute magnitude of −0.13.

<span class="mw-page-title-main">14 Trianguli</span> Star in the constellation Triangulum

14 Trianguli, also known as HD 15656, is a spectroscopic binary located in the northern constellation Triangulum. It has an apparent magnitude of 5.14, making it faintly visible to the naked eye in ideal conditions. Gaia DR3 parallax measurements place the system 433 light years away, and it is currently approaching the Solar System with a heliocentric radial velocity of −37 km/s. At its current distance, 14 Tri's brightness is diminished by 0.21 magnitude due to interstellar dust. It has an absolute magnitude of −0.46.

<span class="mw-page-title-main">WZ Columbae</span> Star in the constellation of Columba

WZ Columbae, also known as HD 38170, is a solitary, bluish-white hued star located in the southern constellation Columba, the dove. It has an apparent magnitude of 5.28, allowing it to be faintly visible to the naked eye. Based on parallax measurements from the Gaia spacecraft, the object is about 365 light years distant. It appears to be receding from the Solar System, having a heliocentric radial velocity of 36.3 km/s.

HD 34255, also known HR 1720, is a star located in the northern circumpolar constellation Camelopardalis, the giraffe. It has an apparent magnitude of 5.60, allowing it to be faintly visible to the naked eye. The object is located relatively far at a distance of about 1.65 kly but is approaching the Solar System with a heliocentric radial velocity of −7.7 km/s.

HD 50885, also known as HR 2581, is a star located in the northern circumpolar constellation Camelopardalis, the giraffe. It has an apparent magnitude of 5.69, making it faintly visible to the naked eye if viewed under ideal conditions. Based on parallax measurements from Gaia DR3, the object is estimated to be 513 light years distant. It appears to be approaching the Solar System with a heliocentric radial velocity of −17.8 km/s.

HD 43899, also designated as HR 2263, is a solitary, orange hued star located in the southern constellation Columba, the dove. It has an apparent magnitude of 5.53, allowing it to be faintly visible to the naked eye. Based on parallax measurements from the Gaia spacecraft, the object is estimated to be 284 light years distant. It appears to be rapidly receding with a heliocentric radial velocity of 66.5 km/s. Eggen (1993) lists HD 43899 as an old disk star and its kinematics match with that of the ζ Herculis moving group.

<span class="mw-page-title-main">HD 198716</span> Star in the constellation of Microscopium

HD 198716, also known as HR 7987 or 33 G. Microscopii, is a solitary star located in the southern constellation Microscopium. Eggen (1993) lists it as a member of the Milky Way's old disk population.

<span class="mw-page-title-main">HD 197630</span> Star in the constellation of Microscopium

HD 197630, also known as HR 7933 or rarely 23 G. Microscopii, is a probable astrometric binary located in the southern constellation Microscopium. The visible component is a bluish-white hued star that is faintly visible to the naked eye with an apparent magnitude of 5.47. Based on parallax measurements from the Gaia satellite, the system is estimated to be 328 light years away. However, it is drifting closer with a heliocentric radial velocity of −30 km/s. At its current distance, HD 197630's brightness is diminished by 0.11 magnitudes due to interstellar dust. A 2012 multiplicity survey failed to confirm the velocity variations.

<span class="mw-page-title-main">HD 168592</span> Star in the constellation of Corona Australis

HD 168592, also designated as HR 6862 or rarely 7 G. Coronae Australis, is a solitary star located in the southern constellation Corona Australis. It is faintly visible to the naked eye as an orange-hued star with an apparent magnitude of 5.07. Gaia DR3 parallax measurements place it at a distance of 490 light years and is currently receding with a heliocentric radial velocity of 18 km/s. At its current distance, HD 168592's brightness is diminished by 0.38 magnitudes due to interstellar dust. It has an absolute magnitude of −0.76.

<span class="mw-page-title-main">HD 175219</span> K-type giant; Corona Australis

HD 175219, also known as HR 7122, is a solitary, orange hued star located in the southern constellation Corona Australis. It has an apparent magnitude of 5.35, allowing it to be faintly visible to the naked eye. The object is located relatively close at a distance of 314 light years based on Gaia DR3 parallax measurements but is drifting closer with a heliocentric radial velocity of −21.1 km/s. At its current distance, HD 175219's brightness is diminished by 0.26 magnitudes due to interstellar dust. It has an absolute magnitude of +0.57.

<span class="mw-page-title-main">HD 170642</span> A-type dwarf; Corona Australis

HD 170642, also designated as HR 6942 or rarely 13 G. Coronae Australis, is a single star located in the southern constellation Corona Australis. It is faintly visible to the naked eye as a white hued star with an apparent magnitude of 5.16. The object is located relatively close at a distance of 229 light years based on Hipparcos parallax measurements, but it is approaching the Solar System with a somewhat constrained heliocentric radial velocity of −6 km/s. At its current distance, HD 170642's brightness is diminished by 0.28 magnitudes due to interstellar dust. It has an absolute magnitude of +0.93.

<span class="mw-page-title-main">HD 31134</span> Star in the constellation of Camelopardalis

HD 31134, also designated as HR 1561, is a solitary star located in the northern circumpolar constellation Camelopardalis, the giraffe. It is faintly visible to the naked eye as a white-hued star with an apparent magnitude of 5.74. Gaia DR3 parallax measurements place it 473 light years away. It appears to be approaching the Solar System with a heliocentric radial velocity of −15.1 km/s. At its current distance, HD 31134's brightness is diminished by 0.35 magnitudes due to interstellar dust. It has an absolute magnitude of +0.19.

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