HD 28527

HD 28527
Observation data; Epoch J2000 Equinox J2000
Constellation	Taurus
Right ascension	04h 30m 33.633s
Declination	+16° 11′ 38.46″
Apparent magnitude (V)	4.78
Characteristics
Spectral type	A6 IV or A7 V
B−V color index	+0.170±0.001
Variable type	suspected δ Sct
Astrometry
Radial velocity (Rv)	+38.1±0.8 km/s
Proper motion (μ)	RA: +104.422 mas/yr ; Dec.: −26.254 mas/yr
Parallax (π)	22.0357 ± 0.2516 mas
Distance	148 ± 2 ly ; (45.4 ± 0.5 pc)
Absolute magnitude (MV)	+1.58
Details
Mass	1.75 M☉
Radius	2.209 R☉
Luminosity	19.03 L☉
Surface gravity (log g)	4.17±0.14 cgs
Temperature	8,274±281 K
Metallicity [Fe/H]	+0.30 dex
Rotation	1.278 d
Rotational velocity (v sin i)	87.5 km/s
Age	307 Myr
Other designations
	NSV 1627, BD+15°637, GJ 170.1/9157, HD 28527, HIP 21029, HR 1427, SAO 93975
Database references
SIMBAD	data

HD 28527 is a star in the constellation Taurus, and a member of the Hyades open cluster.^[8] It is faintly visible to the naked eye with an apparent visual magnitude of 4.78.^[2] The distance to this star, as determined from its parallax shift of 22 mas,^[1] is 148 light years. It is moving away from the Earth with a heliocentric radial velocity of +38 km/s.^[2]

Based upon a stellar classification of A6 IV by Cowley et al. (1969),^[3] this is an A-type subgiant star that has consumed the hydrogen at its core and is evolving away from the main sequence. Older studies had it classed as an A-type main-sequence star with a class of A7 V.^[4] At the age of 307^[7] million years, it has a high rate of spin, revolving upon its axis once every 1.278 days.^[8] It is a Delta Scuti variable^[5] with 1.75^[7] times the mass of the Sun and 2.2^[8] times the Sun's radius. The star is radiating 19^[2] times the Sun's luminosity from its photosphere at an effective temperature of 8,274 K.^[7]

Due to its location near the ecliptic, this star is subject to lunar occultations. These events have provided occasional, but not definitive, evidence of a close secondary companion.^[11]^[12] Eggleton and Tokovinin (2008) catalogue this as a possible triple star system, having the inner pair being similar stars with an angular separation of 0.02″, and the outer component a magnitude 6.7 star of class F2 at a much wider separation of 250″.^[13]

References

^ ^a ^b ^c ^d ^e ^f 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.
^ ^a ^b ^c ^d ^e ^f ^g 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.
^ ^a ^b 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.
^ ^a ^b Ljunggren, B.; Oja, T. (1961), "The Uppsala spectral classification", Uppsala Astronomical Observatory Annual, 4 (10): 10, Bibcode:1961UppAn...4j...1L.
^ ^a ^b Samus', N. N.; et al. (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
^ Eggen, Olin J. (July 1998), "The Age Range of Hyades Stars", The Astronomical Journal, 116 (1): 284–292, Bibcode:1998AJ....116..284E, doi:10.1086/300413.
^ ^a ^b ^c ^d ^e ^f ^g 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.
^ ^a ^b ^c ^d ^e ^f van Saders, Jennifer L.; Pinsonneault, Marc H. (October 2013), "Fast Star, Slow Star; Old Star, Young Star: Subgiant Rotation as a Population and Stellar Physics Diagnostic", The Astrophysical Journal, 776 (2): 20, arXiv:1306.3701, Bibcode:2013ApJ...776...67V, doi:10.1088/0004-637X/776/2/67, S2CID 119097746, 67.
^ Gebran, M.; et al. (November 2010), "Chemical composition of A and F dwarfs members of the Hyades open cluster", Astronomy and Astrophysics, 523: A71, arXiv:1006.5284, Bibcode:2010A&A...523A..71G, doi:10.1051/0004-6361/200913273, S2CID 7164596.
^ "HD 161840". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-08-06.
^ Peterson, D. M.; Baron, R. L.; Dunham, E.; Mink, D.; Weekes, T. C.; Elliot, J. L. (February 1981), "Lunar occultations of the Hyades: 1979-1980", Astronomical Journal, 86: 280–289, Bibcode:1981AJ.....86..280P, doi:10.1086/112886.
^ Richichi, A.; et al. (October 1999), "New binary stars discovered by lunar occultations. IV", Astronomy and Astrophysics, 350: 491–496, Bibcode:1999A&A...350..491R.
^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.

[GaiaDR2-1] ^ ^a ^b ^c ^d ^e ^f 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.

[Anderson2012-2] ^ ^a ^b ^c ^d ^e ^f ^g 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.

[Cowley1969-3] 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.

[Ljunggren1961-4] Ljunggren, B.; Oja, T. (1961), "The Uppsala spectral classification", Uppsala Astronomical Observatory Annual, 4 (10): 10, Bibcode:1961UppAn...4j...1L.

[gcvs-5] Samus', N. N.; et al. (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.

[Eggen1998-6] Eggen, Olin J. (July 1998), "The Age Range of Hyades Stars", The Astronomical Journal, 116 (1): 284–292, Bibcode:1998AJ....116..284E, doi:10.1086/300413.

[David2015-7] ^ ^a ^b ^c ^d ^e ^f ^g 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.

[vanSaders2013-8] ^ ^a ^b ^c ^d ^e ^f van Saders, Jennifer L.; Pinsonneault, Marc H. (October 2013), "Fast Star, Slow Star; Old Star, Young Star: Subgiant Rotation as a Population and Stellar Physics Diagnostic", The Astrophysical Journal, 776 (2): 20, arXiv:1306.3701, Bibcode:2013ApJ...776...67V, doi:10.1088/0004-637X/776/2/67, S2CID 119097746, 67.

[Gebran2010-9] Gebran, M.; et al. (November 2010), "Chemical composition of A and F dwarfs members of the Hyades open cluster", Astronomy and Astrophysics, 523: A71, arXiv:1006.5284, Bibcode:2010A&A...523A..71G, doi:10.1051/0004-6361/200913273, S2CID 7164596.

[SIMBAD-10] "HD 161840". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-08-06.

[Peterson1981-11] Peterson, D. M.; Baron, R. L.; Dunham, E.; Mink, D.; Weekes, T. C.; Elliot, J. L. (February 1981), "Lunar occultations of the Hyades: 1979-1980", Astronomical Journal, 86: 280–289, Bibcode:1981AJ.....86..280P, doi:10.1086/112886.

[Richichi1999-12] Richichi, A.; et al. (October 1999), "New binary stars discovered by lunar occultations. IV", Astronomy and Astrophysics, 350: 491–496, Bibcode:1999A&A...350..491R.

[Eggleton2008-13] Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.

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HD 28527

See also

References

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