WDS 21069+3845 STF 2758 AF : NOTES
 
 
discov_num notes refcode
STF2758 61 Cyg. According to R.G. Aitken, this was discovered in 1753 by A__1935f
Bradley. Premature orbits have been computed for AB. This is an Bdy1832A
example of a binary known by its common parallax and proper motion
rather than the orbital motion, which has completed approximately
one-sixth of an orbit in the past 200 years. The extremely large
proper motion of this pair has led to some confusion in identification
of others stars measured relative to the primary. Precise epoch-2000
coordinates and UCAC2 catalog cross-identifications are listed below:
A = UCAC2 50084730 = 2106539+384457 pm = +5328 +3258
B = UCAC2 50084732 = 2106552+384431 pm = +5267 +3143
C = UCAC2 45407969 = 2106142+383502 +007+006
D = UCAC2 45407870 = 2105597+384133 +002-006
E = UCAC2 45408060 = 2106306+384532 +012-007
F = UCAC2 45408067 = 2106322+384246 +019-002
G = UCAC2 45408111 = 2106413+384325 +000-002
H = UCAC2 45408157 = 2106502+384551 -004-006
The Aa pair was renamed AF. The G and H components were both initially
believed to be the C component. B is BD+38@4344.
AB: Statistically the same parallax within the errors would indicate
the components are physical.
AB: H 4 18. MEv2010
An estimated mass has been used by Josties (1981) to compute the Jti1981
otherwise nearly indeterminate orbit; thus the orbit should not be
used to compute the mass. The RV difference from which the ascending
node is inferred is quite small. Various small variations, formerly
suspected in the period range of about 5-10 years, are absent in the
strong photographic coverage of the last decades.
See Baize & Petit (1989) catalog of doubles with variable component. Baz1989d
Resulting component masses are 0.74 +/- 0.13 and 0.46 +/- 0.07 Msun. PkO2006b
HIP 104214. See Allen et al. (2000) for information on metallicity, AlC2000
age, galactic orbital parameters, etc.
CHARA Array Limb-darkened diameter of A,B: CIA2008e
1.775 +/- 0.013, 1.581 +/- 0.022 mas.
R = 0.665 +/- 0.005, 0.595 +/- 0.008 \rsun,
L = 0.153 +/- 0.010, 0.085 +/- 0.007 \lsun,
Teff = 4400 +/- 100, 4040 +/- 80 K.
AB: NLTT 50559/50560 Chm2004
BC: Optical pair, based on study of relative motion of the components
using the method of apparent motion parameters. Kiy2008
Inclination of orbit flipped by 180 deg in accordance with available Pko2017b
data by cataloger.
Analysis of long term photometric variability of both components PkO2019a
reliable photometric variability with periods of about 15 years and
variation of 0.05(0.02) magnitudes for both components as well as a
9 year variation for B.
HZE 4 Heinze et al. (2010) determine that the J, K, and L components are all
background objects. Hze2010
STF2758 AC, AE, AF, AG, AH: Rectilinear solutions by Mason & Hartkopf (2016). Msn2016a
SMR 1 AI: Rectilinear solution by Mason & Hartkopf (2016). Msn2016a
SMR 40 AO, AP: Rectilinear solutions by Mason & Hartkopf (2016). Msn2016a
STF2758 BC: Rectilinear solution by Mason & Hartkopf (2016). Msn2016a
FYM 106 BN: Rectilinear solution by Mason & Hartkopf (2016). Msn2016a
 
 
REFERENCES
 
 
refcode metd author reference
A__1935f - Aitken, R.G. 1935QB821.A3.......
A__1935f The Binary Stars, 1935
AlC2000 Po - Allen, C., Poveda, A., & Herrera, M 2000A&A...356..529A
AlC2000 A&A 356, 529, 2000
Baz1989d - Baize, P. & Petit, M. 1989A&AS...77..497B
Baz1989d A&AS 77, 497, 1989
Bdy1832A Ma - Bradley, J. 1833MmRAS...5...13H
Bdy1832A Memoirs, Oxford, 1832
Bdy1832A (as cited by Herschel, MemRAS 5, 13, 1833)
Chm2004 E - Chaname, J. & Gould, A. 2004ApJ...601..289C
Chm2004 ApJ 601, 289, 2004
Chm2004 (Photometry, coordinates, and astrometry from rNLTT. Astrometry from early
Chm2004 versions of 2MASS and UCAC, with date given only as "circa 2000". Measures
Chm2004 identical to discovery observations - predominantly close pairs - were assumed
Chm2004 not new observations, so not included in WDS. Similar concerns when primary and
Chm2004 secondary magnitudes or proper motions were the same.)
CIA2008e not j Kervella, P., Merand, A., Pichon, B., Thevenin, F., Heiter, U., Bigot, L., 2008A&A...488..667K
CIA2008e ten Brummelaar, T.A., McAlister, H.A., Ridgway, S.T., Turner, N., Sturmann, J., .
CIA2008e Sturmann, L., Goldfinger, P.J. & Farrington, C. .
CIA2008e A&A 488, 667, 2008 .
Hze2010 A j Heinze, A.N., Hinz, P.M., Sivanandam, S., Kenworthy, M., Meyer, M., & Miller, D. 2010ApJ...714.1551H
Hze2010 ApJ 714, 1551, 2010
Kiy2008 - Kiyaeva, O.V., Kiselev, A.A. & Izmailov, I.S. 2008SvAL...32..405K
Kiy2008 SvAL 34, 405, 2008
MEv2010 - MacEvoy, B. ...................
MEv2010 private communication, 2010 (see http://www.handprint.com/ASTRO/index.html)
Msn2016a lin - Mason, B.D. & Hartkopf, W.I. 2016IAUDS.189....1M
Msn2016a Inf. Circ. 189, 1, 2016
PkO2006b orb - Gorshanov, D.L., Shakht, N.A. & Kisselev, A.A. 2006SvA....49..386K
PkO2006b SvA 49, 386, 2006
PkO2017b Po - Shakht, N.A., Gorshanov, D.L. & Vasilkova, O.O. 2017Ap.....60..507S
PkO2017b +orb Astrophysics 60, 507, 2017
PkO2017b Note: Published J2000 PA precessed to epoch of observation for consistency.
 
 
DISCOVERER
 
 
idgroup discov author
1 FYM Fay, M.
28 SMR Schlimmer, J.
83 STF Struve, F.G.W.
116 TNN Tanner, A.M., Gelino, C.R., & Law, N.M.
 
 
WDS HISTORIC DATA
 
 
coord_2000 discov_num comp epoch obs pa sep mag_pri mag_sec spectr notes coord_arcsec_2000
21069+3845 STF2758 AF 1921 2 30 140.6 5.20 11.32 K5V N P 210653.94+384457.8
21069+3845 STF2758 AF 2008 4 242 329.1 5.20 11.32 K5V N DP 210653.94+384457.8
21069+3845 STF2758 AF 2009 5 241 333.8 5.20 11.32 K5V N DP 210653.94+384457.8
21069+3845 STF2758 AF 2011 6 241 346.4 5.20 11.32 K5V N DP 210653.94+384457.8
21069+3845 STF2758 AF 2013 8 240 357.0 5.35 11.30 K5V N P 210653.95+384457.9
21069+3845 STF2758 AF 2014 9 240 360.7 5.35 11.30 K5V N P 210653.95+384457.9
21069+3845 STF2758 AF 2016 10 240 371.2 5.35 11.30 K5V NL P 210653.95+384457.9

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