Orbital elements of selected visual binaries
P = orbital period, in years; T = date of periastron, year and decimals; a = semi-major axis of orbit, arcseconds; e = eccentricity of orbit; i = inclination of orbit to plane of sky, degrees; peri = argument of periastron (usually indicated by a lower-case Greek omega, ω), degrees; node = PA of ascending node (usually indicated by a capital Greek omega, Ω), degrees.
These elements can be entered in this BASIC program to find the separation and position angle of each pair for any required date.
The ADS number (left column) is that given in R. G. Aitken’s New General Catalogue of Double Stars, which extends to declination –30°.
ADS
number
Star
RA
h   m
dec
°   ’
Magnitudes
P
(years)
T
a
e
i
°
peri
ω
°
node
Ω
°
17175
85 Peg
00  02.2
+27  05
5.8
8.9
26.280
2015.7
00.83
0.38
49.00
96.00
290.00
434
Lambda Cas
00  31.8
+54  31
5.3
5.6
536.47
2012.09
01.165
0.816
75.80
260.50
17.40
520
BU 395
00  37.3
–24  46
6.2
6.6
25.020
1998.78
00.675
0.218
78.60
318.10
291.980
671
Eta Cas
00  49.1
+57  49
3.5
7.4
480.000
2369.6
11.994
0.497
34.76
268.59
278.42
755
36 And
00  55.0
+23  38
6.1
6.5
167.510
1956.19
00.984
0.306
44.57
358.62
173.66
1538
STF 186
01  55.9
+01  51
6.8
6.8
165.720
2058.0
00.986
0.726
72.40
219.70
40.20
1598
48 Cas
02  02.0
+70  54
4.7
6.7
61.140
2025.49
00.614
0.355
16.70
19.50
48.20
1615
Alpha Psc
02  02.0
+02  46
4.1
5.2
933.000
2098.6
04.0
0.696
120.90
225.40
23.30
1631
10 Ari
02  03.7
+25  56
5.8
7.9
325.000
1931.6
01.39
0.59
51.00
165.00
20.50
2402
Alpha For
03  12.1
–28  59
4.0
7.2
269.000
1947
04.0
0.73
81.00
43.00
117.00
2616
7 Tau
03  34.4
+24  28
6.6
6.9
522.160
1911.62
00.625
0.679
157.20
238.10
13.00
2799
STT 65
03  50.3
+25  35
5.7
6.5
61.20
1998.30
00.442
0.628
84.70
340.30
26.40
4241
Sigma Ori
05  38.7
–02  36
3.7
6.3
156.700
1999.5
00.266
0.051
159.70
8.70
121.70
5423
Alpha CMa
06  45.1
–16  43
–1.4
8.5
50.090
2044.40
07.500
0.592
136.53
147.27
44.57
5400
12 Lyn AB
06  46.2
+59  27
5.4
6.0
907.60
2677.4
02.30
0.37
134.70
322.60
166.5.
5514
14 Lyn
06  53.1
+59  27
6.0
6.5
316.2
1961.99
00.614
0.441
64.70
170.30
51.00
6175
Alpha Gem
07  34.6
+31  53
1.9
3.0
466.80
1957.3
06.78
0.333
113.56
249.30
41.20
6420
9 Pup
07  51.8
–13  54
5.6
6.5
22.700
1985.92
00.602
0.741
80.40
73.10
102.90
6650
Zeta Cnc AB
08  12.2
+17  39
5.3
6.3
59.580
1989.09
00.859
0.319
173.940
330.20
157.60
6650
Zeta Cnc AB–C
08  12.2
+17  39
5.1
6.2
1115.000
1970
07.7
0.24
146.00
345.50
74.20
6914
BU 208
08  39.1
–22  40
5.4
6.8
123.000
1986.6
01.705
0.33
82.90
309.20
31.80
I 314
08  39.4
–36  36
6.4
7.9
66.500
1992.2
00.527
0.86
102.00
341.00
55.70
Delta Vel
08  44.7
–54  43
var.
5.1
146.9700
2000.78
02.002
0.482
105.60
8.50
344.70
6993
Epsilon Hya
08  46.8
+06  25
3.5
6.7
990.000
1920
04.66
0.30
39.00
200.00
49.30
7307
STF 1338
09  21.0
+38  11
6.7
7.1
303.270
2023.25
01.336
0.254
29.90
191.90
137.30
7390
Omega Leo
09  28.5
+09  03
5.7
7.3
117.970
1959.22
00.860
0.562
65.35
302.54
325.98
Psi Vel
09  30.7
–40  28
3.9
5.1
33.950
2003.63
00.862
0.433
58.00
44.30
291.00
7545
Phi UMa
09  52.1
+54  04
5.3
5.4
105.400
1987.4
00.349
0.45
24.50
35.00
130.30
7555
Gamma Sex
09  52.5
–08  06
5.4
6.4
77.820
2035.47
00.397
0.736
141.10
303.3
194.70
7724
Gamma Leo
10  20.0
+19  51
2.4
3.6
510.300
2181.6
04.24
0.845
117.60
162.54
143.40
7846
BU 411
10  36.1
–26  41
6.7
7.8
170.140
1948.39
00.886
0.765
128.20
37.90
145.10
8119
Xi UMa
11  18.2
+31  32
4.3
4.8
59.880
1995.07
02.536
0.398
122.13
127.94
101.85
8148
Iota Leo
11  23.9
+10  32
4.1
6.7
186.000
1948.8
01.91
0.53
128.00
325.00
235.00
8197
STT 235
11  32.4
+61  05
5.7
7.6
72.700
1981.8
00.79
0.40
46.00
132.00
80.00
8539
STF 1639
12  24.4
+25  35
6.7
7.8
575.440
1891.75
01.224
0.926
150.40
9.70
140.80
8573
BU 28
12  30.1
–13  24
6.5
9.6
151.000
1944
01.4
0.71
24.00
75.00
94.00
Gamma Cen
12  41.5
–48  58
2.8
2.9
84.490
2015.71
00.936
0.791
113.50
187.20
2.40
8630
Gamma Vir
12  41.7
–01  27
3.5
3.5
169.100
2005.51
03.639
0.882
149.46
255.00
35.340 
8695
35 Com
12  53.3
+21  15
5.2
7.1
359.000
2038.0
01.181
0.145
34.00
30.00
201.40
8974
25 CVn
13  37.5
+36  18
5.0
7.0
228.000
2092.0
01.02
0.80
147.00
159.00
87.00
Alpha Cen
14  39.6
–60  50
0.0
1.3
79.914
2035.49
17.575
0.518
79.21
231.65
204.85
9343
Zeta Boo
14  41.1
+13  44
4.5
4.6
124.460
2023.65
02.3
0.998
102.30
262.90
8.20
9413
Xi Boo
14  51.4
+19  06
4.8
7.0
151.600
2060.9
04.94
0.51
139.00
203.00
347.00
9425
STT 288
14  53.4
+15  42
6.9
7.6
313.000
2137
01.36
0.50
108.50
49.00
12.50
9494
44,i Boo
15  03.8
+47  39
5.2
var.
209.800
2012.04
03.67
0.511
83.550
39.86
57.14
9617
Eta CrB
15  23.2
+30  17
5.6
6.0
41.630
1975.55
00.862
0.279
58.08
39.88
202.83
9626
Mu2 Boo
15  24.5
+37  23
7.1
7.6
257.000
2121.2
01.47
0.58
134.00
336.00
174.00
Gamma Lup
15  35.1
–41  10
3.5
3.6
190.000
2075.0
00.655
0.51
95.00
311.50
94.60
9909
Xi Sco AB
16  04.4
–11  22
5.2
4.9
45.900
1997.22
00.654
0.744
34.50
163.80
25.30
9979
Sigma CrB
16  14.7
+33  52
5.6
6.5
726.000
1825.2
05.26
0.72
32.30
57.30
28.00
10087
Lambda Oph
16  30.9
+01  59
4.2
5.2
129.000
2068.7
00.91
0.611
23.00
157.50
53.30
10157
Zeta Her
16  41.3
+31  36
3.0
5.4
34.450
2002.15
01.33
0.46
131.00
111.00
50.00
10279
20 Dra
16  56.4
+65  02
7.1
7.3
422.220
2261.13
01.044
0.143
96.00
216.20
68.30
10345
Mu Dra
17  05.3
+54  28
5.7
5.7
812.000
1946.19
04.48
0.51
142.20
193.30
282.90
MlbO 4 AB
17  19.0
–34  59
6.4
7.4
42.150
2018.1
01.81
0.58
128.00
247.00
313.00
10660
26 Dra
17  35.0
+61  52
5.3
8.5
76.100
2023.1
01.53
0.18
104.00
307.00
151.00
11005
Tau Oph
18  03.1
–08  11
5.3
5.9
2570..0.
2086
01.40
0.77
52.00
42.00
60.00
11046
70 Oph
18  05.5
+02  30
4.2
6.2
88.380
1984.30
04.526
0.501
121.1
193.40
121.70
HJ 5014
18  06.8
–43  25
5.7
5.7
450.000
2304.7
02.04
0.65
123.10
282.70
85.80
11483
STT 358
18  35.9
+16  59
6.9
7.1
380.000
2196
01.84
0.57
119.00
74.00
30.80
11635
Epsilon1 Lyr AB
18  44.3
+39  40
5.0
6.1
1725....0
1915
04.17
0.243
118.60
198  0
198.00
11635
Epsilon2 Lyr CD
18  44.4
+39  37
5.3
5.4
724.300
2223.9
02.92
0.35
126.10
73.80
26.20
Gamma CrA
19  06.4
–37  04
4.5
6.4
121.760
2000.64
01.896
0.320
149.60
349.00
50.30
12880
Delta Cyg
19  45.0
+45  08
2.9
6.3
780.300
1880.0
03.0
0.47
151.00
120.20
91.40
14296
Lambda Cyg
20  47.4
+36  29
4.7
6.3
391.300
2186.3
00.78
0.45
133.80
298.40
138.60
14360
4 Aqr
20  51.4
–05  38
6.4
7.4
194.000
2090.3
00.86
0.489
67.30
46.20
174.50
14499
Epsilon Equ AB
20  59.1
+04  18
6.0
6.3
101.485
2021.855
00.647
0.705
92.17
340.19
105.15
14636
61 Cyg
21  06.9
+38  45
5.4
6.1
678.000
2387
24.27
0.49
24.27
149.00
178.00
14787
Tau Cyg
21  14.8
+38  03
3.8
6.6
49.6200
1989.07
00.913
0.239
134.44
298.770
339.750
15270
Mu Cyg
21  44.1
+28  45
4.8
6.2
789.000
1958.0
05.32
0.66
75.50
145.70
110.10
15971
Zeta Aqr
22  28.8
–00  01
4.3
4.5
486.700
1982.73
03.38
0.343
141.70
273.00
133.20
16538
Pi Cep
23  07.9
+75  23
4.6
6.8
162.800
1934.57
00.81
0.597
30.00
90.00
90.30
16836
72 Peg
23  34.0
+31  20
5.7
6.1
492.310
1904.92
00.568
0.32
21.70
293.00
56.20

Orbital elements from the Sixth Catalog of Orbits of Visual Binary Stars by William I. Hartkopf and Brian D. Mason

Page last updated 2012 August.

Earlier versions of this table have appeared in Norton’s Star Atlas (Ian Ridpath, ed.)