Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Microscopium |
Right ascension | 21h 13m 03.06827s [1] |
Declination | −39° 25′ 29.7097″ [1] |
Apparent magnitude (V) | 5.26 [2] |
Characteristics | |
Spectral type | F5 IV-V [3] or F6 V Fe−0.9 CH−0.5 [4] |
B−V color index | +0.44 [2] |
Astrometry | |
Radial velocity (Rv) | −41±1 [5] km/s |
Proper motion (μ) | RA: +185.855 mas/yr [1] Dec.: −113.449 mas/yr [1] |
Parallax (π) | 29.2823 ± 0.0827 mas [1] |
Distance | 111.4 ± 0.3 ly (34.15 ± 0.10 pc) |
Absolute magnitude (MV) | +2.66 [6] |
Details | |
Mass | 1.5 [1] M☉ |
Radius | 2.18±0.09 [7] R☉ |
Luminosity | 7.83±0.04 [1] L☉ |
Surface gravity (log g) | 3.91±0.09 [8] cgs |
Temperature | 6,519±80 [9] K |
Metallicity [Fe/H] | −0.18±0.03 [10] dex |
Rotational velocity (v sin i) | 10 [11] km/s |
Age | 2.23±0.04 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 201772, also known as HR 8104, is a yellowish-white hued star located in the southern constellation Microscopium. It has an apparent magnitude of 5.26, [2] making it one of the brighter members of this generally faint constellation. The object is located relatively close at a distance of 111 light-years based on Gaia DR3 parallax measurements [1] but is approaching closer with a heliocentric radial velocity of −41 km/s . [5] At its current distance, HD 201772's brightness is diminished by 0.11 magnitudes due to interstellar dust. [14]
The star has been given multiple stellar classifications over the years. It was given the luminosity class of a subgiant and main sequence star (IV/V; IV-V) [15] [3] and a dwarf (V). [16] [17] Most sources generally agree that it is a F5 star. Richard O. Gray and colleagues give HD 201772 a class of F6 V Fe−0.9 CH−0.5, which indicates that it is a F-type main-sequence star with an underabundance of iron and CH molecules in its spectrum. [4]
It has 1.47 times the mass of the Sun [18] and an enlarged radius of 2.2 R☉. [7] It radiates 7.8 times the luminosity of the Sun from its photosphere at an effective temperature of 6,519 K . [9] At an age of 2.5 billion years, HD 201722 is currently 1.33 magnitudes above the ZAMS, consistent with a star that is evolving off the main sequence. [11] The star has an iron abundance 66% that of the Sun, [10] making it metal deficient. It spins modestly with a projected rotational velocity of 10 km/s . [11]
HD 201772 is suspected to be a spectroscopic binary consisting of the subgiant described above and an ordinary F6 V star with a mass of 1.31 M☉. [19] However, the stars have no separation or an orbital period. [20] This is because the companion might be a result of spectrum contamination, so HD 201772 is more likely to be a solitary star. [21]
HD 101930, also known as Gliese 3683, is an orange hued star located in the southern constellation Centaurus. It has an apparent magnitude of 8.21, making it faintly visible in binoculars but not to the naked eye. The system is located relatively close at a distance of 98 light years but is receding with a heliocentric radial velocity of 18.4 km/s. A 2007 multicity survey found a co-moving companion located 73″ away, making it a binary star. It has a class of M0-1 and a mass of 0.7 M☉.
HD 63454, formally named Ceibo, is a star located in the southern circumpolar constellation Chamaeleon near the border with Mensa To see the star, one needs a small telescope because it has an apparent magnitude of 9.36, which is below the limit for naked eye visibility. The object is located relatively close at a distance of 123 light years based on Gaia DR3 parallax measurements but is receding with a heliocentric radial velocity of 33.8 km/s. At its current distance, HD 63454's brightness is diminished by two tenths of a magnitude due to interstellar dust. It has an absolute magnitude of +6.68.
HD 88218 is a binary star in the southern constellation Antlia. The system has a combined apparent magnitude of 6.14, making it faintly visible to the naked eye. HD 88218 is relatively close at a distance of 103 light years but is receding with a heliocentric radial velocity of 36.7 km/s.
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.
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.
HD 203842, also known as HR 8191 or rarely 30 G. Equueli, is a solitary, yellowish-white hued star located in the constellation Equuleus. It has an apparent magnitude of 6.32, placing it near the limit for naked eye visibility, even under ideal conditions. Gaia DR3 parallax measurements imply a distance of 374 light years, and it is currently drifting closer with a somewhat constrained heliocentric radial velocity of −21.8 km/s. At its current distance HD 203842's brightness is diminished by 0.15 magnitudes due to interstellar dust and it has an absolute magnitude of +1.06.
HD 97413 is a binary star located in the southern constellation Centaurus. The system has a combined magnitude of 6.27, placing it near the limit for naked eye visibility. Based on parallax measurements from the Gaia spacecraft, the system is located 320 light years away from the Solar System.
HD 63399 is an orange hued star located in the southern constellation Puppis, the poop deck. It has an apparent magnitude of 6.45, placing it near the limit for naked eye visibility. Based on parallax measurements from Gaia DR3, the object is estimated to be 445 light years distant. It appears to be receding with a spectroscopic radial velocity of 28.5 km/s. At its current distance, HD 63399 is diminished by 0.29 magnitudes due to interstellar dust.
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.
HD 193307 is the primary of a binary star located the southern constellation Telescopium. It has an apparent magnitude of 6.27, placing it near the limit for naked eye visibility, even under ideal conditions. The star is located relatively close at a distance of 102 light years based on Gaia DR3 parallax measurements, but it is receding with a heliocentric radial velocity of 16.9 km/s. At its current distance, HD 193307's brightness is diminished by 0.18 magnitudes due to extinction from interstellar dust and it has an absolute magnitude of +3.80. HD 193307 has a relatively high proper motion, moving at a rate of 437 mas/yr.
HD 28454, also known as HR 1418, is a solitary, yellowish-white hued star located in the southern constellation Caelum, the chisel. It has an apparent magnitude of 6.1, making it faintly visible to the naked eye under ideal conditions. This star is located relatively close at a distance of about 107 light years based on parallax measurements of Gaia DR3 but is receding with a heliocentric radial velocity of 15 km/s.
HD 27022, also known as HR 1327, is a star located in the northern circumpolar constellation Camelopardalis. The object has also been designated as 20 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.27, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the star has been estimated to be 347 light years away. It appears to be approaching the Solar System, having a heliocentric radial velocity of −19.5 km/s.
HD 208741, also known as HR 8380, is a yellowish-white hued star located in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.91, making it faintly visible to the naked eye. Parallax measurements place it at a distance of 211 light years, and it is currently receding with a heliocentric radial velocity of 8 km/s.
HD 26670, also known as HR 1305, is a star located in the northern circumpolar constellation of Camelopardalis, the giraffe. The object has been designated as 26 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.70, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the object is estimated to be 491 light years away from the Solar System. It appears to be slowly receding with a heliocentric radial velocity of 0.4 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.
HR 8526, also known as HD 212168, is the primary of a triple star located in the southern circumpolar constellation Octans. The star and its companion have apparent magnitudes of 6.12 and 9.36 respectively. The system is located relatively close at a distance of 76 light years based on Gaia DR3 parallax measurements, but is receding with a heliocentric radial velocity of 15 km/s.
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.
HD 22764, also known as HR 1112, is an orange hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.78, allowing it to be faintly visible to the naked eye. The object is located relatively far at a distance of approximately 1,770 light years based on Gaia DR3 parallax measurements but is approaching the Solar System with a heliocentric radial velocity of −12.5 km/s. At its current distance, HD 22764's brightness is diminished by 0.66 magnitudes due to interstellar dust.
HD 204018, also designated as HR 8202, is a visual binary located in the southern constellation Microscopium. The primary has an apparent magnitude of 5.58, making it faintly visible to the naked eye under ideal conditions. The companion has an apparent magnitude of 8.09. The system is located relatively close at a distance of 176 light years based on Gaia DR3 parallax measurements but is receding with a heliocentric radial velocity of 18.3 km/s. At its current distance, HD 204018's combined brightness is diminished by 0.13 magnitudes due to interstellar dust.
HD 202908, also known as HIP 105200, is a triple star located in the equatorial constellation Equuleus. It has an apparent magnitude of 7.01, making it readily visible in binoculars but not to the naked eye. When resolved, the components have apparent magnitudes of 7.25 and 8.87 respectively. The system is located relatively close at a distance of 169 light years based on Gaia DR3 parallax measurements but it is receding with a heliocentric radial velocity of 6.24 km/s.