59 Serpentis

This article is about d Serpentis. Not to be confused with δ Serpentis.

59 Serpentis

A light curve for 59 Serpentis, plotted from Hipparcos data[1]
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Serpens
Right ascension	18^h 27^m 12.50775^s[2]
Declination	00° 11′ 45.9912″[2]
Apparent magnitude (V)	5.17 – 5.29[3]
Characteristics
Spectral type	A0Vs + G:III[2]
U−B color index	+0.21[4]
B−V color index	+0.48[4]
Variable type	Irregular?[3]
Astrometry
Radial velocity (Rv)	−23.3[5] km/s
Proper motion (μ)	RA: −3.67[6] mas/yr Dec.: −8.61[6] mas/yr
Parallax (π)	6.95 ± 0.63 mas[6]
Distance	470 ± 40 ly (140 ± 10 pc)
Absolute magnitude (MV)	−0.57[7]
Details
Aa
Mass	6.32[8] M☉
Radius	13[9] R☉
Temperature	5,093[10] K
Age	316[10] Myr
Ab1
Mass	4.13[8] M☉
Radius	2.2[9] R☉
Temperature	9,700[9] K
Ab2
Mass	3.39[8] M☉
Radius	1.8[9] R☉
Temperature	9,700[9] K
Ba
Mass	3.17[8] M☉
Radius	1.7[11] R☉
Luminosity	10.1[11] L☉
Surface gravity (log g)	4.28[11] cgs
Temperature	7,981[11] K
Other designations
59 Ser, d Ser, HIP 90441, HR 6918, BD+00°3936, ADS 11353, CCDM J18272+0012
A: HD 169985
B: HD 169985
Database references
SIMBAD	data
	A
	B

59 Serpentis, also known as d Serpentis, is a multiple star in the constellation Serpens.^[2] The system shows irregular variations in brightness between magnitudes 5.17 and 5.29.^[3]

Components

59 Serpentis appears as a close pair of stars, of 5th magnitude and 7th magnitude respectively, separated by four arc-seconds. The brighter of the two is itself an even closer binary with the two stars separated by only 0.2″, and only 0.1″ when they were first detected. The stars are designated Aa, Ab, and B.^[12]

The primary star, component Aa, is a G0 giant. Component Ab is spectroscopic binary with a period of 1.85 days; the two stars are very similar A-class main sequence stars. Component B is an F5V possible astrometric binary, but with little known about the orbit or the possible companion.^[8]

A much fainter star 20″ away is also thought to be a member of the system, having a common proper motion and similar Gaia parallax, and is designated as component C.^[8]

References

1. "Hipparcos Tools Interactive Data Access". Hipparcos. ESA. Retrieved 8 December 2021.
2. "d Serpentis -- Double or multiple star". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 2 July 2014.
3. VSX (4 January 2010). "d Serpentis". AAVSO Website. American Association of Variable Star Observers. Retrieved 25 May 2014.
4. Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
5. Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Carnegie Institute Washington D.C. Publication. Bibcode:1953GCRV..C......0W.
6. 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.
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.
8. Tokovinin, Andrei (2018-03-01). "The Updated Multiple Star Catalog". The Astrophysical Journal Supplement Series. 235 (1): 6. arXiv:1712.04750. Bibcode:2018ApJS..235....6T. doi:10.3847/1538-4365/aaa1a5. ISSN 0067-0049. S2CID 119047709.
9. Tilley, Elizabeth Cornwall (1943). "A Spectrographic Study of the Triple System in 59 D Serpentis". The Astrophysical Journal. 98: 347. Bibcode:1943ApJ....98..347T. doi:10.1086/144577.
10. Parsons, Sidney B. (May 2004). "New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions". The Astronomical Journal. 127 (5): 2915–2930. Bibcode:2004AJ....127.2915P. doi:10.1086/383546.
11. Stassun K.G.; et al. (October 2019). "The revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. S2CID 166227927.
12. Mason, Brian D.; et al. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.