111 Herculis

111 Herculis
	Location of 111 Herculis (circled in red)
Observation data; Epoch J2000 Equinox ICRS
Constellation	Hercules
Right ascension	18h 47m 01.23431s
Declination	+21° 46′ 53.4578″
Apparent magnitude (V)	4.34
Characteristics
Evolutionary stage	main sequence
Spectral type	A3Va+
B−V color index	0.148±0.003
Astrometry
Radial velocity (Rv)	−44.6±2.7 km/s
Proper motion (μ)	RA: +98.835 mas/yr ; Dec.: +115.120 mas/yr
Parallax (π)	34.9987±0.1743 mas
Distance	93.2 ± 0.5 ly ; (28.6 ± 0.1 pc)
Absolute magnitude (MV)	2.04
Details
Mass	2.40 M☉
Radius	1.6 R☉
Luminosity	12.84 L☉
Surface gravity (log g)	4.35 cgs
Temperature	8,873±302 K
Metallicity [Fe/H]	0.33 dex
Rotational velocity (v sin i)	71 km/s
Age	559 Myr
Other designations
	111 Her, BD+18°3823, FK5 1491, HD 173880, HIP 92161, HR 7069, SAO 104093, WDS J18470+1811
Database references
SIMBAD	data

111 Herculis is a suspected astrometric binary star system located 92 light years from the Sun in the northern constellation Hercules. It is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.34. The system is moving nearer to the Earth with a heliocentric radial velocity of −45 km/s, and may come as close as 37 light-years in 537,000 years.

According to Garrison (1989), the visible component has a spectral classification if A3Va+, indicating an A-type main sequence star. Other authors have published classes of A5III, matching an A-type giant star, and A3IV, suggesting it is instead a subgiant star. Models of the star's evolution suggest that it is still on the main sequence.

The interferometry-measured angular diameter of the primary component is 0.52±0.02 mas, which, at its estimated distance, equates to a physical radius of roughly 1.6 times the radius of the Sun. The star is estimated to be 559 million years old with 2.40 times the mass of the Sun and is spinning with a projected rotational velocity of 71 km/s. It is radiating 13 times the Sun's luminosity from its photosphere at an effective temperature of 8,873 K.

References

1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
1 2 3 4 5 6 7 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.
↑ Gray, R. O.; Garrison, R. F. (1989). "The Late A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation". The Astrophysical Journal Supplement Series. 70: 623. Bibcode:1989ApJS...70..623G. doi:10.1086/191349.
1 2 3 4 5 6 7 8 9 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
1 2 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R_*) is given by:
$\begin{matrix} 2 \cdot R_{*} & = \frac{(1 0^{- 3} \cdot 28.3 \cdot 0.52) AU}{0.0046491 AU / R_{⨀}} \\ \approx 3.2 \cdot R_{⨀} \end{matrix}$
↑ Erspamer, D.; North, P. (February 2003), "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs. II. Abundances of 140 A-F stars from ELODIE", Astronomy and Astrophysics, 398 (3): 1121–1135, arXiv:astro-ph/0210065, Bibcode:2003A&A...398.1121E, doi:10.1051/0004-6361:20021711, S2CID 1109164.
↑ "111 Her". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-18.
↑ 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.
↑ Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819
↑ 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.
↑ Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics, 431 (2): 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039

[GaiaDR3-1] 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.

[Anderson2012-2] 1 2 3 4 5 6 7 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.

[mk-3] Gray, R. O.; Garrison, R. F. (1989). "The Late A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation". The Astrophysical Journal Supplement Series. 70: 623. Bibcode:1989ApJS...70..623G. doi:10.1086/191349.

[David2015-4] 1 2 3 4 5 6 7 8 9 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.

[lang2006-5] 1 2 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, vol. 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1. The radius (R_*) is given by:
$\begin{matrix} 2 \cdot R_{*} & = \frac{(1 0^{- 3} \cdot 28.3 \cdot 0.52) AU}{0.0046491 AU / R_{⨀}} \\ \approx 3.2 \cdot R_{⨀} \end{matrix}$

[Erspamer2003-6] Erspamer, D.; North, P. (February 2003), "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs. II. Abundances of 140 A-F stars from ELODIE", Astronomy and Astrophysics, 398 (3): 1121–1135, arXiv:astro-ph/0210065, Bibcode:2003A&A...398.1121E, doi:10.1051/0004-6361:20021711, S2CID 1109164.

[SIMBAD-7] "111 Her". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-18.

[Eggleton2008-8] 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.

[Cowley1969-9] Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819

[abt1995-10] 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.

[Richichi2005-11] Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics, 431 (2): 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039