- Double Stars (Cnc) -

And (32) Cep (13) CVn (4) Her (13) Mon (1) Sex (2)
Aql (9) Cet (1) Cyg (19) Hya (4) Oph (1) Tau (11)
Ari (8) CMa (1) Del (2) Leo (19) Ori (8) Tri (4)
Aur (27) Cnc (10) Dra (8) Lib (1) Peg (16) UMa (24)
Boo (12) Com (8) Equ (5) LMi (6) Per (18) UMi (1)
Cam (10) CrB (4) Eri (1) Lyn (18) Psc (7) Vir (6)
Cas (17) Crv (1) Gem (19) Lyr (8) Ser (2)

STF 1171 (**)

Name: STF1171
Type: **
Constellation: Cnc
Coordinates: 08h01m00.78s / +23°34'59.20"

Components:
m1 m2 ρ θ Year
6m5 9m9 2.0" 326° 2015
Robert Zebahl
102mm f/11, 187x
Observation from the city at half moon. At magnifications between 187x and 280x I could see the very dim companion almost permanently near the first diffraction ring. But the diffraction ring itself was hardly visible. Main problem here was probably the low brightness of the companion.

STF 1177 (**)

Name: STF1177, 17 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h05m37.06s / +27°31'46.90"

Components:
m1 m2 ρ θ Year
6m7 7m4 3.6" 350° 2019
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
Easy to separate, but still relatively close together. Well visible difference in brightness. Color of the components was not clearly visible. Nice view overall.

STF 1187 (**)

Name: STF1187
Type: **
Constellation: Cnc
Coordinates: 08h09m30.45s / +32°13'18.80"

Components:
m1 m2 ρ θ Year
AB 7m2 8m0 3.1" 20° 2019

../images/binary-star-orbits/STF1187-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
Split. Components very tight with noticeable difference in brightness.

STF 1196 & HUT1 (**)

Name: STF1196 & HUT1, zeta Cnc, 16 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h12m12.79s / +17°38'51.20"

Components:
m1 m2 ρ θ Year
STF1196 AC 5m3 5m8 6.3" 51° 2019
STF1196 AB-C 4m9 5m8 6.0" 64° 2018
STF1196 AB 5m3 6m2 1.1" 2018
HUT1 Ca-Cb 6m2 7m1 0.3" 233° 2018

../images/binary-star-orbits/STF1196-AB-C-orbit.jpg ../images/binary-star-orbits/STF1196-AB-orbit.jpg ../images/binary-star-orbits/HUT1-Ca-Cb-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6-
The wide pair AB-C is already separable at 22x. The pair AB shows at 133x two clearly overlapping diffraction disks with small difference in brightness, but without any notch.

../sketches/2020-03-24_stf1196.jpg

102mm f/11, 86x, Bortle 6-, SQM-L 19.2
AB-C: Easy to separate. A: light grey, B: pale orange.

120mm f/5, 67x, Bortle 6, SQM-L 19.3
AB-C: Evident difference in brightness, easy to split. Both components of similar color.

120mm f/5, 200x, Bortle 6, SQM-L 19.3
AB: Very tight. The Airy disks were still touching. Slight difference in brightness. Extremely beautiful triple star!

../sketches/2019-02-24_stf1196.jpg

STF 1245 (**)

Name: STF1245
Type: **
Constellation: Cnc
Coordinates: 08h35m51.05s / +06°37'13.90"

Components:
m1 m2 ρ θ Year
AB 6m0 7m2 10.1" 25° 2018
AC 6m0 10m7 100.4" 109° 2017
AD 6m0 11m9 110.3" 292° 2017
AE 6m0 9m6 114.8" 207° 2017
Robert Zebahl
70mm f/5.7, 57x, Bortle 6-
AB at 22x separated, but very close, uneven pair. A appeared white-yellowish, B orange, partly reddish. Opposite in a wide separation the fainter component E was visible. At 57x, A appeared white-yellowish, B orange.

../sketches/2020-03-24_stf1245.jpg

STF 1268 (**)

Name: STF1268, iota Cnc, 48 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h46m41.82s / +28°45'35.60"

Components:
m1 m2 ρ θ Year
4m1 6m0 30.7" 308° 2018
Robert Zebahl
70mm f/5.7, 22x, Bortle 6, SQM-L 19.4
Striking, widely separated with noticeable difference in brightness. Moderate but beautiful color contrast: white-yellowish and grey-bluish.

102mm f/11, 28x
Grand sight! Pretty wide apart and unequal. A: decent orange, B: very nice light blue.

STF 1291 (**)

Name: STF1291, 57 Cnc
Type: **
Constellation: Cnc
Coordinates: 08h54m14.65s / +30°34'45.80"

Components:
m1 m2 ρ θ Year
AB 6m1 6m4 1.6" 309° 2019
AB-C 5m5 9m2 54.6" 204° 2015

../images/binary-star-orbits/STF1291-AB-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.4
AB: Immediately apparent as a double star. Diffraction disks overlapping slightly ('8'). Difference in brightness visible.

STF 1294 & SIN41 (**)

Name: STF1294 & SIN41
Type: **
Constellation: Cnc
Coordinates: 08h57m17.08s / +32°53'57.90"

Components:
m1 m2 ρ θ Year
STF1294 AB 9m0 10m8 15.6" 340° 2015
SIN41 AC 9m0 12m6 191.3" 285° 2015
Robert Zebahl
102mm f/11, 28x, Bortle 6-, SQM-L 19.0
STF1294 (AB): At 28x relatively widely separated and rather less striking near the bright star sigma 2 Cnc. Component A appeared slightly orange, the companion only as a dim star. Similar view at 86x.

STF 1298 (**)

Name: STF1298, 66 Cnc
Type: **
Constellation: Cnc
Coordinates: 09h01m24.13s / +32°15'08.30"

Components:
m1 m2 ρ θ Year
AB 6m0 8m6 4.4" 137° 2017
AC 6m0 12m0 187.6" 318° 2015
Robert Zebahl
70mm f/5.7, 80x, Bortle 6, SQM-L 19.4
AB: At 67x and 80x the companion is visible as a very faint star close to the main component. At 133x it is only visible as a slightly blurred tiny star just outside the first diffraction ring of the primary component.

102mm f/11, 62x, Bortle 6-, SQM-L 19.0
AB: At 62x clearly separated, significant difference in brightness. The companion can be seen well as a faint little star, apart from the primary component. At 125x easy to split. Component A appeared rather white.

STT 195 (**)

Name: STT195
Type: **
Constellation: Cnc
Coordinates: 08h53m57.80s / +08°25'17.70"

Components:
m1 m2 ρ θ Year
AB 7m7 8m3 9.8" 139° 2017
Robert Zebahl
70mm f/5.7, 80x, Bortle 6-
At 22x very nicely separated with a small difference in brightness. The components are still pretty tight. Altogether a rather dim double star. At 80x the color difference is well visible: primary component appears slightly orange, the companion pale blue.