52 Herculis

A light curve for V637 Herculis, plotted from TESS data[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Hercules
Right ascension 16h 49m 14.21821s[2]
Declination +45° 58′ 59.9620″[2]
Apparent magnitude (V) 4.82[3] (4.87 + 8.85[9.0 + 9.1])[4]
Characteristics
Evolutionary stage main sequence[4]
Spectral type A1VpSiSrCr[5] + K0V?[4]
B−V color index 0.087±0.003[3]
Variable type α2 CVn[6]
Astrometry
Radial velocity (Rv)−1.6±0.5[3] km/s
Proper motion (μ) RA: +22.57[2] mas/yr
Dec.: −51.35[2] mas/yr
Parallax (π)18.10 ± 0.34 mas[2]
Distance180 ± 3 ly
(55 ± 1 pc)
Absolute magnitude (MV)1.16 + 5.47 + 5.57[7]
Orbit[7]
Primary52 Her A
Companion52 Her B
Period (P)56.4±0.3 yr
Semi-major axis (a)0.279±0.005″
Eccentricity (e)0.13±0.02
Inclination (i)37.4+2.6
−2.8°
Longitude of the node (Ω)57.5°
Periastron epoch (T)1991.2
Argument of periastron (ω)
(secondary)		69.4°
Details[8]
52 Her A
Mass2.19+0.14
−0.22 M☉
Radius2.30±0.11 R☉
Luminosity29.5+2.1
−2.0 L☉
Surface gravity (log g)4.06+0.05
−0.06 cgs
Temperature8,840±190 K
Rotational velocity (v sin i)23.2±1.4 km/s
Age525+234
−162 Myr
Other designations
52 Her, V637 Her, BD+46°2220, HD 152107, HIP 82321, HR 6254, SAO 46305, WDS J16492+4559[9]
Database references
SIMBADdata

52 Herculis is a triple star[7][4] system in the northern constellation of Hercules. It is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.82.[3] Based upon parallax measurements, the system is located 180 light years away from the Sun. It is moving closer to the Earth with a heliocentric radial velocity of −1.6 km/s.[3]

The primary member, designated component A, is a magnetic[10] chemically peculiar star[8] with a stellar classification of A1VpSiSrCr,[5] appearing as an A-type main-sequence star with abnormal abundances of silicon, strontium, and chromium. It is an alpha2 Canum Venaticorum variable that ranges in brightness from visual magnitude 4.78 down to 4.85 with a period of 3.8567 days.[6] The star is about 525 million years old with a projected rotational velocity of 23 km/s. It has 2.2 times the mass of the Sun and 2.3 times the Sun's radius. The star is radiating 29.5 times the Sun's luminosity from its photosphere at an effective temperature of 8,840 K.[8]

The remaining components form a binary star system with an orbital period of 56 years, an angular semimajor axis of 0.279″, and an eccentricity of 0.13.[7] They have an angular separation of 1.78″ from the primary.[4] The total mass of the pair is 1.16±0.09 M☉[7] and they have a combined visual magnitude of 8.85.[4] The brighter member of this pair is a suspected K-type main-sequence star with a class of K0V.

References

  1. ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 28 November 2022.
  2. ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  3. ^ a b c d e 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.
  4. ^ a b c d e f 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.
  5. ^ a b Abt, H. A. (1981), "Visual multiples. VII - MK classifications", The Astrophysical Journal Supplement Series, 45: 437, Bibcode:1981ApJS...45..437A, doi:10.1086/190719.
  6. ^ a b Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
  7. ^ a b c d e De Rosa, R. J.; et al. (2012), "The Volume-limited A-Star (VAST) survey - II. Orbital motion monitoring of A-type star multiples", Monthly Notices of the Royal Astronomical Society, 422 (4): 2765, arXiv:1112.3666, Bibcode:2012MNRAS.422.2765D, doi:10.1111/j.1365-2966.2011.20397.x, S2CID 102487103.
  8. ^ a b c Sikora, J.; et al. (February 2019), "A Volume-Limited Survey of mCP Stars Within 100pc I: Fundamental Parameters and Chemical Abundances", Monthly Notices of the Royal Astronomical Society, 483 (2): 2300–2324, arXiv:1811.05633, Bibcode:2019MNRAS.483.2300S, doi:10.1093/mnras/sty3105, S2CID 119089236.
  9. ^ "52 Her". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-14.
  10. ^ Bychkov, V. D.; et al. (April 2012), "Magnetic field of the Ap star 52 Her", Astrophysical Bulletin, 67 (2): 207–215, Bibcode:2012AstBu..67..207B, doi:10.1134/S199034131202006X, S2CID 120468594
Categories