HD 221525

Last updated
HD 221525
Cepheus IAU.svg
Cercle rouge 100%25.svg
Location of HD 221525 (circled)
Observation data
Epoch J2000.0        Equinox J2000.0
Constellation Cepheus
Right ascension 23h 27m 00.91338s [1]
Declination 87° 18 27.0304 [1]
Apparent magnitude  (V)5.56 [2]
Characteristics
Spectral type A8III [3] or A7IV [4]
B−V color index 0.250±0.004 [2]
Astrometry
Radial velocity (Rv)−10.9±2.9 [2]  km/s
Proper motion (μ)RA: +75.736 [1]   mas/yr
Dec.: +16.724 [1]   mas/yr
Parallax (π)10.3023 ± 0.0957  mas [1]
Distance 317 ± 3  ly
(97.1 ± 0.9  pc)
Absolute magnitude  (MV)0.52 [2]
Details
Mass 2.25? [5]   M
Radius 3.98+0.11
−0.13
[1]   R
Luminosity 44.3±0.5 [1]   L
Temperature 7466+217
−105
[1]   K
Rotational velocity (v sin i)110 [4]  km/s
Age ~900 [5]   Myr
Other designations
BD+86°3444, HD  221525, HIP  115746, HR  8938, SAO  3916 [6]
Database references
SIMBAD data

HD 221525 is a single [7] star near the north celestial pole [5] in the constellation Cepheus. At an apparent magnitude of 5.56, [2] it can be seen with the naked eye under dark skies. It is about 30 times fainter than the nearby prominent star Polaris. [8] Based upon parallax measurements, HD 221525 is located at a distance of approximately 317  light years from the Sun, [1] but is drifting closer with a radial velocity of −11 km/s. [2]

This object is an A-type star with a stellar classification of A7IV [4] or A8III, [3] suggesting it is an evolving star on the subgiant or giant branch, respectively. It has a relatively high rate of spin, showing a projected rotational velocity of 110 km/s. [4] The star has four [1] times the radius of the Sun and is radiating 44 [1] times the Sun's luminosity from its photosphere at an effective temperature of 7,466 K. [1]

Related Research Articles

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Chi Scorpii, Latinized from χ Scorpii, is a single star in the zodiac constellation of Scorpius. It has an orange hue and can be faintly seen with the naked eye with an apparent visual magnitude of 5.22. Based upon parallax measurements, this star is around 409 light years from the Sun. The star is drifting closer with a radial velocity of −23.6 km/s.

68 Aquarii is a single star located 270 light years away from the Sun in the zodiac constellation of Aquarius. 68 Aquarii is its Flamsteed designation, though it also bears the Bayer designation of g2 Aquarii. It is visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 5.24. The object is moving further from the Earth with a heliocentric radial velocity of +24.5 km/s.

<span class="mw-page-title-main">36 Aurigae</span> Star in the constellation Auriga

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17 Canis Majoris is a single star in the southern constellation of Canis Major, located 610 light years away from the Sun. It is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude of 5.80. The object is moving closer to the Earth with a heliocentric radial velocity of −13 km/s.

E Centauri is a single star in the southern constellation of Centaurus. It is a white-hued star that is dimly visible to the naked eye with an apparent visual magnitude of +5.34. The distance to this object is approximately 560 light years based on parallax, and it has an absolute magnitude of −0.97. It is drifting closer to the Sun with a radial velocity of +7 km/s, and it is a candidate member of the Lower Centaurus Crux subgroup of the Sco OB2 association.

HD 41534 is a binary star system in the southern constellation of Columba. It is dimply visible to the naked eye with a combined apparent visual magnitude of 5.65. The distance to this system is approximately 950 light-years based on parallax, and it is receding from the Sun with a radial velocity of +93 km/s. This is a runaway star system with an unusually high peculiar velocity of 187.6+12.2
−13.8
 km/s
. It is thought to have been ejected from the OB association Sco OB 1 approximately 14 million years ago.

HD 171301 is a suspected binary star system in the northern constellation of Lyra. It has not been well-studied. The brighter member of the pair, designated component A, has a blue-white hue and is visible to the naked eye with an apparent visual magnitude of 5.47. The system is located at a distance of approximately 347 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −10 km/s.

HD 167965 is a single star in the northern constellation of Lyra. It is dimly visible to the naked eye on a sufficiently dark night, having an apparent visual magnitude of 5.56. The star is located at a distance of approximately 590 light years from the Sun based on parallax. It is drifting closer with a radial velocity of −20.5 km/s and is predicted to come as near as 72.7 light-years in around 8.5 million years.

Omega<sup>1</sup> Aquilae Star in the constellation Aquila

Omega1 Aquilae, which is Latinized from ω1 Aquilae, is the Bayer designation for a single star in the equatorial constellation of Aquila. With an apparent visual magnitude of 5.2 it is a faint, yellow-white hued star that can be seen with the naked eye in dark skies. From the annual parallax shift of 8.53 mas, the distance to this star can be estimated as 382 light-years, give or take a 6 light year margin of error. It is drifting closer to the Sun with a radial velocity of −14 km/s.

HD 35520 is a single star in the northern constellation of Auriga. It has a white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.92. The distance to this star is approximately 2,200 light years based on parallax. The radial velocity for the star is, as yet, poorly constrained.

Beta Horologii, Latinized from β Horologii, is the third-brightest star in the southern constellation of Horologium. It is faintly visible to the naked eye with an apparent visual magnitude of 4.98. Based upon an annual parallax shift of 11.07 mas as seen from Earth, it is located about 295 light years from the Sun. The star is moving away with a radial velocity of +24 km/s.

5 Camelopardalis is a binary star system in the northern circumpolar constellation of Camelopardalis, located about 770 light years away from the Sun as determined using parallax. With an apparent magnitude of 5.5, it can be seen with the naked eye as a faint, blue-white hued star. The system is moving further from the Earth with a heliocentric radial velocity of +2.4 km/s.

63 Cygni is a single star in the northern constellation of Cygnus, located around 1,030 light years away from Sun. It is visible to the naked eye as an orange-hued star with an apparent visual magnitude of 4.56. 63 Cyg is moving closer to the Earth with a heliocentric radial velocity of −26 km/s.

HD 32309 is a single star in the southern constellation of Lepus. It has a blue-white hue and is visible to the naked eye with an apparent visual magnitude of 4.91. The distance to this object is 197 light years based on parallax. It is drifting further away from the Sun with a radial velocity of +24 km/s. This is a member of the Columba association of co-moving stars.

κ2 Lupi, Latinized as Kappa2 Lupi, is a white-hued star in the southern constellation of Lupus, and forms a double star with Kappa1 Lupi. It is visible to the naked eye as a dim point of light with an apparent visual magnitude is 5.64. This star is located around 181 light years distant from the Sun. It is an A-type main-sequence star with a stellar classification of A3/5V. However, Levato (1973) classed the star as A3IV, which would suggest it is already evolving off the main sequence. The star has a high rotation rate, showing a projected rotational velocity of 160 km/s.

HR 6875, previously known as Sigma Telescopii, is a single star in the constellation Corona Australis. It has a blue-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.24. This object is located at a distance of approximately 550 light years from the Sun based on parallax. It is listed as a member of the Sco OB2 association.

HR 4339 is a single star in the equatorial constellation of Hydra. It was designated as Beta Antliae by Lacaille, and Gould intended to keep it in that constellation. However, the delineating of constellation boundaries by the IAU in 1930 saw it transferred to Hydra. It has a white hue and is just visible to the naked eye with an apparent visual magnitude of 5.79. The distance to this star, as determined from parallax measurements, is approximately 366 light years. It is drifting further away with a radial velocity of +1.3 km/s.

Gamma<sup>2</sup> Fornacis Star in the constellation Fornax

Gamma2 Fornacis, a name Latinized from γ2 Fornacis, is a single star in the southern constellation Fornax. It has a white hue and is faintly visible to the naked eye at night with an apparent visual magnitude of 5.4. The distance to Gamma2 Fornacis is approximately 520 light years based on parallax. It is drifting further away with a radial velocity of 24 km/s. Gamma1 Fornacis is a 6th magnitude star about four degrees to the north.

HD 53501, is a solitary star in the southern circumpolar constellation Volans. It has an apparent magnitude of 5.18, allowing it to be seen with the naked eye under ideal conditions. The object is located at a distance of 308 light years but is receding with a heliocentric radial velocity of 39 km/s.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
  2. 1 2 3 4 5 6 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971 . Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID   119257644.
  3. 1 2 Abt, Helmut A.; Morrell, Nidia I. (1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". Astrophysical Journal Supplement. 99: 135. Bibcode:1995ApJS...99..135A. doi: 10.1086/192182 .
  4. 1 2 3 4 Cowley, Anne; Fraquelli, Dorothy (1974). "MK Spectral Types for Some Bright F Stars". Publications of the Astronomical Society of the Pacific. 86 (509): 70. Bibcode:1974PASP...86...70C. doi: 10.1086/129562 .
  5. 1 2 3 Jim Kaler. "HR 306 and HR 8938". Stars.astro.illinois.edu. Retrieved 2012-02-29.
  6. "HD 221525". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-11-21.
  7. Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society . 389 (2): 869–879. arXiv: 0806.2878 . Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID   14878976.
  8. Calculation: