- Double Stars (CVn) -

And (43) Cet (1) Del (4) Lib (1) Per (27) UMi (1)
Aql (9) CMa (2) Dra (11) LMi (6) Psc (10) Vir (9)
Ari (8) Cnc (10) Equ (5) Lyn (18) Pup (1) Vul (3)
Aur (28) Com (8) Eri (1) Lyr (11) Ser (3)
Boo (20) CrB (4) Gem (22) Mon (1) Sex (2)
Cam (11) Crv (1) Her (16) Oph (1) Tau (11)
Cas (17) CVn (11) Hya (4) Ori (9) Tri (4)
Cep (13) Cyg (26) Leo (24) Peg (16) UMa (37)

25 CVn (**)
Name: 25 CVn
Type: **
Constellation: CVn
Coordinates: 13h37m27.70s / +36°17'41.40"

Components:
m1 m2 ρ θ Year
STF1768 AB 5m0 7m0 1.7" 99° 2018
STF1768 AC 5m0 11m6 214.3" 321° 2015
KZA73 AD 5m0 13m0 335.6" 92° 2015
KZA73 AE 5m0 12m7 369.5" 139° 2015
KZA73 AF 5m0 9m4 437.3" 118° 2015

../images/binary-star-orbits/STF1768-AB-orbit.jpg

Robert Zebahl
60mm f/18.7, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 60mm. The diffraction ring of the primary component is virtually invisible. The companion appears only in few moments as an extremely faint, elongated brightening in the diffraction ring. Very difficult. Telescope should be in very good optical condition!
70mm f/16, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 70mm. Companion only visible as a subtle, elongated, not permanently visible brightening. The diffraction ring of the primary component is only visible occasionally. Difficult. Telescope should be in good optical condition!
80mm f/14, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 80mm. Companion permanently visible as elongated brightening in the diffraction ring. But the diffraction ring itself appears rather faint. Moderately difficult.
90mm f/12.5, 160x
AB: 2020-03-16: 102/1122mm ED refractor stopped down to 90mm. Companion quite clearly recognizable as elongated brightening in diffraction ring. Relatively simple.
102mm f/11, 160x
AB: 2020-03-16: The faint companion is immediately recognizable as a distinct, slightly elongated brightening in the diffraction ring. Easy.
152mm f/5.9, 150x, Bortle 6-, SQM-L 19.1
AB: 2020-03-19: At 150x the clearly fainter companion is visible as a roundish brightening. Due to the chromatic aberration of the achromat (152mm f/5.9) the companion is almost outshined. At 180x the companion is then well, at 225x and 300x very well visible as a tiny separated star.

AG 190 (**)
Name: AG190
Type: **
Constellation: CVn
Coordinates: 13h35m38.82s / +49°39'21.70"

Components:
m1 m2 ρ θ Year
9m6 9m8 2.6" 13° 2017
Robert Zebahl
70mm f/5.7, 80x, Bortle 6, SQM-L 19.4
2020-04-20: Pretty faint double star. At 80x still very tight pair with little difference in brightness. Not very attractive.

STF 1692 (**)
Name: STF1692, 12 CVn, alpha CVn, Cor Caroli
Type: **
Constellation: CVn
Coordinates: 12h56m01.67s / +38°19'06.20"

Components:
m1 m2 ρ θ Year
AB 2m9 5m5 19.5" 230° 2018
Robert Zebahl
70mm f/5.7, 22x
Beautiful view. Clearly unequal with nice angular distance. Primary component appeared in pale yellow, companion silvery-white.
4.5" f/8, 28x, Bortle 6, NELM 5m3, SQM-L 19.7
Well split with big difference in brightness.

STF 1747 (**)
Name: STF1747
Type: **
Constellation: CVn
Coordinates: 13h27m45.73s / +47°45'32.20"

Components:
m1 m2 ρ θ Year
9m3 10m2 14.9" 345° 2015
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.4
2020-04-20: Easy to separate. The primary component appeared slightly orange with a noticeably fainter companion.

STF 1755 (**)
Name: STF1755
Type: **
Constellation: CVn
Coordinates: 13h32m21.99s / +36°49'05.60"

Components:
m1 m2 ρ θ Year
7m3 8m1 4.1" 133° 2018
Robert Zebahl
70mm f/5.7, 67x, Bortle 6-, NELM 5m0, SQM-L 19.1
At 31x just separable, extremely tight. At 44x clearly separated, but still close, relatively dim pair with moderate difference in brightness. At 67x and 100x well separable. The primary component appeared slightly orange.

STF 1758 (**)
Name: STF1758
Type: **
Constellation: CVn
Coordinates: 13h32m51.51s / +49°08'24.30"

Components:
m1 m2 ρ θ Year
8m7 8m9 3.3" 291° 2015
Robert Zebahl
70mm f/5.7, 67x, Bortle 6, SQM-L 19.4
2020-04-20: Clearly split, still relatively tight pair with little difference in brightness. The components appear slightly different in color: slightly orange, yellowish.

STF 1786 (**)
Name: STF1786
Type: **
Constellation: CVn
Coordinates: 13h49m38.98s / +34°59'18.10"

Components:
m1 m2 ρ θ Year
AB 8m9 10m3 11.0" 22° 2015
Robert Zebahl
70mm f/5.7, 44x, Bortle 6, SQM-L 19.4
2020-04-20: Nicely separated at an attractive distance and with a clear difference in brightness. The components appeared pale orange and greyish.

STF 1789 (**)
Name: STF1789
Type: **
Constellation: CVn
Coordinates: 13h54m05.19s / +32°49'35.20"

Components:
m1 m2 ρ θ Year
8m6 9m0 6.7" 328° 2015
Robert Zebahl
70mm f/5.7, 31x, Bortle 6, SQM-L 19.4
2020-04-20: At 22x clearly visible as figure '8' and almost separated. At 31x fine separation of the still close pair. A slight difference in brightness and color is visible: white-yellowish, yellowish-orange.

STFA 24 (**)
Name: STFA24
Type: **
Constellation: CVn
Coordinates: 13h10m03.27s / +38°29'55.90"

Components:
m1 m2 ρ θ Year
AB 6m0 6m3 275.6" 296° 2012
This double star contains of the components 15 and 17 CVn.
Robert Zebahl
B 8x40, Bortle 7, NELM 5m0, SQM-L 19.2
Both components similar in brightness with large distance.

STT 261 (**)
Name: STT261
Type: **
Constellation: CVn
Coordinates: 13h12m02.02s / +32°05'07.90"

Components:
m1 m2 ρ θ Year
7m4 7m6 2.6" 339° 2017

../images/binary-star-orbits/STT261-orbit.jpg

Robert Zebahl
70mm f/5.7, 57x, Bortle 6, SQM-L 19.4
2020-04-20: At 44x immediately visible as figure '8', even separable on closer look. The components appeared similarly bright. Overall rather dim. At 57x clearly split, but still very close together with a small difference in brightness.

STT 274 (**)
Name: STT274
Type: **
Constellation: CVn
Coordinates: 14h06m41.61s / +34°46'42.80"

Components:
m1 m2 ρ θ Year
7m1 10m5 12.9" 51° 2018
Robert Zebahl
70mm f/5.7, 133x, Bortle 6, SQM-L 19.4
2020-04-20: At 100x and 133x no signs of the faint companion visible.