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Apperant Orbits of Binary Stars


Written by Toshimi Taki
July 28, 2007

1. Introduction

I present figures of apparent orbits of binary stars. Each figure includes a table of the apparent positions (position angles and sepparations). I used the MS-Excel worlsheet presented in 3. Astronomical Computing to make the figures.

(1) Position Angle and Deparation
The figure below shows the definition of Position Angle and Separation.




(2) Dawes Criterion
The resolving power for point sources was empirically established by Dawes.
Dawes Criterion is 117/D arcseconds and D is the aperture in millimeter. Note that this criteion is for the same brightness of the point light sources. If the magnitudes of the components of a binary star are different, the resolving power is reduced.

Aperture (mm) 50 75 100 150 200 250 300
Resolving Power (arc second) 2.34 1.56 1.17 0.78 0.59 0.47 0.39

Aperture (inch) 2 3 4 6 8 10 12.5
Resolving Power (arc second) 2.30 1.54 1.15 0.77 0.58 0.46 0.37



2. Database

All the necessary data are available via Internet.

[1] W. I. Hartkopf and B. D. Mason, "Sixth Catalog of Orbits of Visual Binary Stars," downloaded on July 17, 2007.
I use the orbital elements in this reference.

[2] C. E. Worley and W. D. Heintz, "Fourth Catalog of Orbits of Visual Binary Stars," 1983.
The spectrum types of the stars are from this reference.

[3] B. D. Mason, G. L. Wycoff, and W. I. Hartkopf, "The Washington Double Star Catalog," downloaded on June 9, 2007.


3. List of Binary Stars

WDS Name ADS Primary Secondary Position at 2007.0 Constel.
Mag. Sp. Type Mag. Sp. Type P.A. (deg.) Sep. (arc sec.)
00022+2705 85 Peg/ BU 733AB ADS 17175 5.8 G2V 8.9 -- 249 0.84 Peg
00063+5826 STF 3062 ADS 61 6.42 G3V 7.32 -- 341 1.53 Cas
00093+7943 STF 2 ADS 102 6.68 A7IV 6.89 -- 17.1 0.84 Cep
06451-1643 Alpha CMa/ Sirius/ AGC 1AB ADS 5423 -1.46 A1V 8.5 DA 102 7.62 CMa
12417-0127 Gamma Vir/ Porrima/ STF 1670AB ADS 8630 3.48 F0V 3.53 F0V 60 0.66 Vir
16413+3136 Zeta Her/ STF 2084 ADS 10157 2.95 G0IV 5.4 G7V 205 1.07 Her
17146+1423 Alpha Her/ STF 2140Aa-B ADS 10418 3.48 M5Ib 5.4 G5III 104 4.65 Her
17153-2636 36 Oph/ SHJ 243AB ADS 10417 5.12 K0V 5.12 K1V 144 4.92 Oph
17166-0027 41 Oph/ A 2984 ADS 10429 4.92 -- 7.51 -- 12 1.03 Oph
17571+0004 STF 2244 ADS 10912 6.89 -- 6.56 -- 99 0.53 Oph
18018+0118 68 Oph/ BU 1125AB ADS 10990 4.52 -- 7.48 -- 137 0.58 Oph
18031-0811 Tau Oph/ STF 2262AB ADS 11005 5.27 F4IV 5.86 -- 284 1.66 Oph
18055+0230 70 Oph/ STF 2272AB ADS 11046 4.22 K0V 6.2 K4V 135 5.25 Oph
18068-4325 HJ 5014 -- 5.65 -- 5.66 -- 3 1.71 CrA
18070+3034 99 Her/ AC 15AB ADS 11077 5.13 F7V 8.96 -- 301 0.94 Her
18096+0400 73 Oph/ STF 2281AB ADS 11111 5.97 F2V 7.52 -- 289 0.61 Oph
18101+1629 STF 2289 ADS 11123 6.65 B9V 7.21 -- 217 1.24 Her
18239+5848 39 Dra/ STF 2323AB ADS 11336 5.06 A1V 8.07 -- 349 3.75 Dra
18250+2724 STF 2315AB ADS 11334 6.57 A1V 7.77 -- 120 0.63 Her
18250-0135 AC 11 ADS 11324 6.71 A9III 7.21 -- 355 0.84 Ser
18355+2336 STT 359 ADS 11479 6.35 G9III 6.62 -- 5 0.72 Her
18359+1659 STT 358AB ADS 11483 6.94 G2V 7.08 G2V 151 1.55 Her
18443+3940 Epsilon 1 Lyr/ STF 2382AB ADS 11635 5.01 A4V 6.1 F1V 348 2.41 Lyr
18443+3940 Epsilon 2 Lyr/ STF 2383Cc-D ADS 11635 5.25 -- 5.38 -- 79 2.36 Lyr
18570+3254 BU 648AB ADS 11871 5.34 G0V 7.96 -- 266 0.94 Lyr
18575+5814 STF 2438 ADS 11897 7.01 A2IV 7.44 -- 359 0.84 Dra
19064-3704 Gamma CrA/ HJ 5084 -- 4.53 -- 6.42 -- 27 1.32 CrA
19121+4951 STF 2486AB ADS 12169 6.54 -- 6.67 -- 205 7.39 Cyg
19172-6640 GLE 3 -- 6.12 -- 6.42 -- 339 0.51 Pav
19418+5032 16 Cyg/ STFA 46Aa-B ADS 12815 6 -- 6.23 -- 133 39.7 Cyg
19450+4508 Delta Cyg/ STF 2579AB ADS 12880 2.89 B9.5IV 6.27 -- 221 2.66 Cyg
19487+3519 STT 387 ADS 12972 7.12 F4V 7.9 -- 129 0.57 Cyg
19535+2405 13 Vul/ DJU 4 -- 4.63 -- 7.37 -- 246 1.31 Vul
19553-0644 STF 2597AB ADS 13104 6.94 -- 7.98 -- 102 0.56 Aql
21069+3845 61 Cyg/ STF 2758AB ADS 14636 5.35 K5V 6.1 K7V 151 31.1 Cyg
21148+3803 Tau Cyg/ AGC 13AB ADS 14787 3.83 F2IV 6.57 -- 255 0.74 Cyg