WDS 02318+8916 STF 93 AB (Polaris) : NOTES
 
 
discov_num notes refcode
STF 93 alp Umi = 1 UMi = Polaris. Cepheid variable and spectroscopic binary,
P = 30y. A close companion has been suspected. The close pair,
measured three time from 1937-1939 by R.H. Wilson using an eyepiece WRH1941b
interferometer, was not seen again until Evans et al. (2006) resolved Evs2006
it with HST. Wilson's measures agree with the combined astrometric/
spectroscopic solution by Gerasimovic (1936), although both orbit and Ger1936
measures are called into dispute by the more recent orbit of Wielan et Wln2000
al. (2000), whose solution includes mass estimates, etc.
NPOI Limb-darkened diameter 3.28 +/- 0.02 mas, NOI1999
R = 46. +/- 3. \rsun.
An earlier orbit by Wyller (1957) was rejected from Fourth Orbit Wye1957
Catalog ("amplitude below noise level") Wor1983
Component B = BD+88@@@7. See discussion of this system by Roemer. Re_1965
While Hipparcos parallax of A 7.56 +/- 0.48 from the original mission HIP1997a
and 7.54 +/- 0.011 mas from the re-reduction, the HST-FGS parallax of VlF2007
B = 6.26 +/- 0.24 mas implies that that A is high luminosity and BdH2018
pulsating in the second overtone if AB is physical, i.e., the distance
to B is the same as A.
The C component was observed by Burnham in the late 19th century, then Bu_1894
not seen again until the early 21st century by Daley and Ashcroft. Dal2006a
The extremely large magnitude makes the pair too close for most large
astrometric surveys.
The D component has also been recently recovered in 2MASS data. TMA2003
According to Jim Daley, the R-I color for C is 0.56 and for D it is
0.67. The V-I color for D is 1.08. Dal2006b
AB: H 4 1. MEv2010
 
 
REFERENCES
 
 
refcode metd author reference
BdH2018 not - Bond, H.E., Nelan, E.P., Evans, N.R., Schaefer, G.H. & Harmer, D. 2018ApJ...853...55B
BdH2018 ApJ 853, 55, 2018
Bu_1894 Ma j Burnham, S.W. 1894PLicO...2....3B
Bu_1894 Pub. Lick Obs. 2, 3, 1894 (includes most data from Bu_1893a) 1893AN....131..329B
Dal2006a C u Daley, J.A. 2006JDSO....2...44D
Dal2006a JDSO 2, 44, 2006
Dal2006b - Daley, J.A. 2006JDSO....2...51D
Dal2006b JDSO 2, 51, 2006
Evs2006 H j Evans, N.R., Franz, O., Massa, D., Mason, B., Walker, R.L., & Marovska, M. 2006PASP..118.1545E
Evs2006 +S PASP 118, 1545, 2006
Ger1936 orb - Gerasimovic, B.P. .
Ger1936 Pulkova Obs. Circ. #19, 1, 1936
HIP1997a Hh - Hipparcos 1997yCat.1239....0E
HIP1997a Hipparcos Catalog, ESA SP-1200, 1997 (incl. Hp photometry, vol. 10)
MEv2010 - MacEvoy, B. ...................
MEv2010 private communication, 2010 (see http://www.handprint.com/ASTRO/index.html)
NOI1999 not j Nordgren, T.E., Germain, M.E., Benson, J.A., Mozurkewich, D., Sudol, J.J., Elias, 1999AJ....118.3032N
NOI1999 II, N.M., Hajian, A.R., White, N.M., Hutter, D.J., Johnston, K.J., Gauss, F.S., .
NOI1999 Armstrong, J.T., Pauls, T.A. & Rickard, L.J. .
NOI1999 AJ 118, 3032, 1999 .
Re_1965 - Roemer, E. 1965ApJ...141.1415R
Re_1965 ApJ 141, 1415, 1965
TMA2003 E2 j 2MASS Catalog .
TMA2003 2MASS Point Src Cat., 2003 all-sky release (http://pegasus.phast.umass.edu/)
TMA2003 (Note: 2MASS photometry also added by cataloguer to 2MASS astrometry published
TMA2003 under other references.)
TMA2003 Thurgood Marshall High School
VlF2007 - van Leeuwen, F. 2007A&A...474..653V
VlF2007 A&A 474, 653, 2007
Wln2000 orb - Wielen, R., Jahreiss, H., Dettbarn, C., Lenhardt, H., & Schwan, H. 2000A&A...360..399W
Wln2000 A&A 360, 399, 2000
Wor1983 - Worley, C.E. & Heintz, W.D. 1983PUSNO..24g...1W
Wor1983 Pub. USNO 24, Pt. 7, 1983 (Fourth Orbit Catalog)
WRH1941b J - Wilson, R.H. 1941PFAO....6b...1W
WRH1941b +Ma Pub. Univ. Penn. 6, Pt.4, 21, 1941
WRH1941b (U and T coded observations per van den Bos, J Obs 34, 85, 1951) 1951JO.....34...85V
Wye1957 orb - Wyller, A.A. 1957AJ.....62..384W
Wye1957 AJ 62, 384, 1957
 
 
DISCOVERER
 
 
idgroup discov author
1 STF Struve, F.G.W.
 
 
WDS HISTORIC DATA
 
 
coord_2000 discov_num comp epoch obs pa sep mag_pri mag_sec spectr notes coord_arcsec_2000
02318+8916 STF 93 AB 2006 59 231 18.2 2.10 9.10 F7:Ib-IIv N D 023147.08+891550.9
02318+8916 STF 93 AB 2009 60 232 18.2 2.10 9.10 F7:Ib-IIv N D 023147.08+891550.9
02318+8916 STF 93 AB 2013 63 233 18.1 2.04 9.10 F7:Ib-IIv N D 023147.08+891550.9
02318+8916 STF 93 AB 2016 64 236 18.4 2.04 9.10 F7:Ib-IIv NV 023149.09+891550.7

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