- Double Stars (Leo) -

And (32) Cep (13) CVn (4) Her (13) Oph (1) Tau (11)
Aql (9) Cet (1) Cyg (19) Hya (1) Ori (8) Tri (4)
Ari (8) CMa (1) Del (2) Leo (14) Peg (16) UMa (11)
Aur (27) Cnc (10) Dra (8) LMi (4) Per (18) UMi (1)
Boo (8) Com (1) Equ (5) Lyn (16) Psc (7) Vir (6)
Cam (5) CrB (4) Eri (1) Lyr (8) Ser (2)
Cas (17) Crv (1) Gem (19) Mon (1) Sex (1)

STF 1399 (**)

Name: STF1399
Type: **
Constellation: Leo
Coordinates: 09h57m02.21s / +19°45'44.60"

Components:
m1 m2 ρ θ Year
7m7 8m4 30.2" 176° 2017
Robert Zebahl
70mm f/5.7, 22x
Easy to split with nice distance and obviously unequal. A conspicuous group of fainter stars is nearby. Main component appeared in a warm-white, fainter somehow darker (partly bluish, partly slightly orange).

STF 1424 (**)

Name: STF1424, gamma Leo, 41 Leo, Algieba
Type: **
Constellation: Leo
Coordinates: 10h19m58.35s / +19°50'29.40"

Components:
m1 m2 ρ θ Year
AB 2m4 3m6 4.9" 126° 2019

../images/binary-star-orbits/STF1424-AB-orbit-solution-1.jpg ../images/binary-star-orbits/STF1424-AB-orbit-solution-2.jpg

Robert Zebahl
55mm f/9.1, 38x, Bortle 6-, SQM-L 19.1
At 38x split, but very tight with noticeable difference in brightness. At 56x and higher beautiful view of both components, which seemed to have similar colors.

../sketches/2019-02-09_gamma_leo.jpg

55mm f/9.1, 59x, Bortle 6, SQM-L 19.5
Very nice unequal double. A appeared yellow-orange, B rather white-bluish.

../sketches/2019-03-09_gamma_leo.jpg

70mm f/5.7, 100x, Bortle 6-
At 67x still a relatively close pair, but well separated with quite a clear difference in brightness. At 100x easy to separate and visible color difference: A yellowish to slightly orange, B white-yellowish.

102mm f/11, 125x, Bortle 7, SQM-L 18.8, Seeing 3/5
Very nicely separated with wonderful contrast in brightness and color. Primary component slightly orange, companion yellowish.
120mm f/5, 66x, Bortle 6-, SQM-L 19.1
At 48x easily seen as double star. It appeared as '8'. At 66x pretty tight with visible difference in brightness.

STF 1426 (**)

Name: STF1426
Type: **
Constellation: Leo
Coordinates: 10h20m32.32s / +06°25'47.60"

Components:
m1 m2 ρ θ Year
AB-C 7m3 9m4 7.6" 2018
AB 8m0 8m3 0.9" 313° 2018

../images/binary-star-orbits/STF1426-AB-orbit.jpg

Robert Zebahl
102mm f/11, 160x, Bortle 6-
AB-C: Quite large angular distance and therefor easy to separate. The C component was pretty faint.
102mm f/11, 160x, Bortle 6-
AB: At first glance elongated, on closer look visible as '8'.

STF 1431 (**)

Name: STF1431
Type: **
Constellation: Leo
Coordinates: 10h25m35.12s / +08°46'35.40"

Components:
m1 m2 ρ θ Year
7m8 9m1 3.6" 76° 2019
Robert Zebahl
70mm f/5.7, 67x
Separable at 67x, but very close together with a clear difference in brightness. Easy to separate at 100x. Next to it the star 44 Leo shines in a striking, bright orange.

STF 1450 (**)

Name: STF1450, 49 Leo
Type: **
Constellation: Leo
Coordinates: 10h35m02.16s / +08°39'01.60"

Components:
m1 m2 ρ θ Year
5m8 7m9 2.2" 156° 2017
Robert Zebahl
70mm f/5.7, 133x
B component appeared as clear brightening on the first diffraction ring of the primary component in the correct position angle.

STF 1487 (**)

Name: STF1487, 54 Leo
Type: **
Constellation: Leo
Coordinates: 10h55m36.80s / +24°44'59.00"

Components:
m1 m2 ρ θ Year
4m5 6m3 6.8" 112° 2019
Robert Zebahl
55mm f/9.1, 27x
At 27x split, but very tight with noticeable difference in brightness. At 71x easy to separate. No visible color difference.

STF 1517 & BU1431 (**)

Name: STF1517 & BU1431, WDS11137+2008
Type: **
Constellation: Leo
Coordinates: 11h13m40.99s / +20°07'43.30"

Components:
m1 m2 ρ θ Year
STF1517 AB 7m5 8m0 0.7" 314° 2017
BU1431 AB-C 7m5 10m8 246.1" 97° 2015

../images/binary-star-orbits/STF1517-AB-orbit.jpg

Robert Zebahl
102mm f/11, 160x, Bortle 7, SQM-L 18.8, Seeing 3/5
STF1517 (AB): 2020-03-27: At 160x the double star immediately appears elongated, but without any noticeable notching or difference in brightness. At 224x not really better. Observation at moderate seeing (3/5).
152mm f/5.9, 225x, Bortle 7, SQM-L 18.8, Seeing 3/5
STF1517 (AB): 2020-03-27: Clearly elongated. In some moments the double star appeared notched with a small difference in brightness. Observation at moderate seeing (3/5).

STF 1521 (**)

Name: STF1521
Type: **
Constellation: Leo
Coordinates: 11h15m20.95s / +27°34'15.60"

Components:
m1 m2 ρ θ Year
7m7 8m1 3.8" 97° 2019
Robert Zebahl
70mm f/5.7, 67x, Bortle 6-, NELM 5m0, SQM-L 19.1
At 44x still very close, finely separated pair with visible difference in brightness, rather faint. At 67x nicely separated, at 100x very easy. Colors were not clearly visible.

STF 1537 (**)

Name: STF1537
Type: **
Constellation: Leo
Coordinates: 11h24m28.94s / +20°37'16.50"

Components:
m1 m2 ρ θ Year
8m2 9m1 2.3" 358° 2019
Robert Zebahl
102mm f/11, Bortle 7, SQM-L 18.8, Seeing 3/5
2020-03-27: At 62x almost, at 86x clearly separated, whereby the components are still very close together. The companion appears rather dim. The slight difference in brightness is already visible at 62x. At 125x the double star shows itself clearly separated. The primary component appears more white, the companion appears a bit warmer in color.

152mm f/5.9, Bortle 7, SQM-L 18.8, Seeing 3/5
2020-03-27: At 49x the double star presents itself clearly elongated, at 69x it is almost separable. The two diffraction disks are well visible. At 100x very nicely separated at still quite small separation. The primary component appears rather white, the companion shows up in a warmer hue. A moderate difference in brightness is visible.

STF 1540 (**)

Name: STF1540, 83 Leo
Type: **
Constellation: Leo
Coordinates: 11h26m45.32s / +03°00'47.20"

Components:
m1 m2 ρ θ Year
AB 6m5 7m5 28.4" 150° 2018
Robert Zebahl
55mm f/9.1, 16x, Bortle 6, SQM-L 19.5
Wonderful double with slight color contrast in a very nice field. Together with tau Leo stunning view. Slightly unequal. A appeared white-yellowish, B rather grey-bluish.

../sketches/2019-03-09_83_leo_tau_leo.jpg

STF 1547 (**)

Name: STF1547, 88 Leo
Type: **
Constellation: Leo
Coordinates: 11h31m44.94s / +14°21'52.20"

Components:
m1 m2 ρ θ Year
AB 6m3 9m1 15.5" 332° 2018

../images/binary-star-orbits/STF1547-AB-orbit.jpg

Robert Zebahl
55mm f/9.1, 42x, Bortle 6, SQM-L 19.5
Well split with moderate distance. Primary component appeared white-yellowish. Pretty unequal pair.

STF 1552 (**)

Name: STF1552, 90 Leo
Type: **
Constellation: Leo
Coordinates: 11h34m42.50s / +16°47'48.90"

Components:
m1 m2 ρ θ Year
AC 6m3 9m8 63.4" 235° 2018
AB 6m3 7m3 3.1" 209° 2018
Robert Zebahl
55mm f/9.1, 42x, Bortle 6, SQM-L 19.5
AB: A and B very tight and unequal. Much fainter component C very wide apart. All components almost in line. Very nice view.

../sketches/2019-03-09_90_leo.jpg

STFA 19 (**)

Name: STFA19, 84 Leo, tau Leo
Type: **
Constellation: Leo
Coordinates: 11h27m56.23s / +02°51'22.50"

Components:
m1 m2 ρ θ Year
AB 5m0 7m5 89.2" 181° 2019
Robert Zebahl
55mm f/9.1, 16x, Bortle 6, SQM-L 19.5
Wonderful double with slight color contrast in a very nice field. Together with 83 Leo stunning view. Noticeable unequal. A appeared white-yellowish with a hint of orange, B grey-bluish.

../sketches/2019-03-09_83_leo_tau_leo.jpg

STT 215 (**)

Name: STT215
Type: **
Constellation: Leo
Coordinates: 10h16m16.05s / +17°44'24.60"

Components:
m1 m2 ρ θ Year
7m2 7m5 1.5" 176° 2019

../images/binary-star-orbits/STT215-orbit.jpg

Robert Zebahl
70mm f/5.7, 133x
Appeared partly separated, partly as '8'. Brightness seemed to be equal.