Double Stars - Best Of

A detailed description of the project, the data sources, additional websites and how you can contribute visual observations and photographs of double stars to the project are summarized in our introduction.

Double Star Lists:
Double/Multiple Stars 49
Visual Observations 266
Sketches 65
Photographs 11
Observers 14
Werner E. Celnik, Berthold Fuchs, Sarah Gebauer, Christopher Hay, Gerd Kohler, Karsten Kopp, Winfried Kräling, Stefan Loibl, Mark McCarthy, René Merting, Uwe Pilz, Jörg S. Schlimmer, Frederik Wanink, Robert Zebahl
m1 m2 ρ θ Year Coordinates (J2000)
★★★ STTA254, WZ Cas AB 7m4 8m3 57.8'' 89° 2018 Cas 00h01m15.85s +60°21'19.00"
AC 7m4 9m6 155.4'' 324° 2015
AD 7m4 10m3 181.4'' 118° 2016
Christopher Hay
Seeheim (Germany)
6x24 AB: Clearly split. A definitely brighter than B. Under a NELM 5m5 sky both components appear weak in these mini-binoculars and no colour impression arises.;
WZ Cas is the variable designation of component A of STTA254. This semiregular carbon star has a mean brightness range of 6m8 to 7m7, and can reach extreme values of 6m3 at one end and 8m8 at the other. Perhaps it was too deep in a minimum at the time of observation to show colour with 1 inch of aperture? 15x45 binoculars revealed colour in this night, see observation below.
Christopher Hay
Seeheim (Germany)
15x45 AB: Wide split. A orange-red, B no particular colour. NELM 5m5, same night as 6x24 observation above.
Robert Zebahl
Leipzig (Germany)
16x70 AB: 2020-08-19: Intense orange & bluish. Very striking.
René Merting
Drachhausen (Germany)
16x70 AB: ein schöner Fernglas-Doppelstern - Komponente A im Westen präsentiert sich dunkelgelb (noch nicht orange), B im Osten ist eher weißlich
René Merting
Drachhausen (Germany)
18x70 AB: ein sehr auffälliger Doppelstern mit einem schönen Farbkontrast - A strahlt gelb, das kurz davor steht, ins Orange über zu gleiten - B wirkt im Kontrast aquamarin, so dezent wie eine typische PN-Farbe
Robert Zebahl
Leipzig (Germany)
80mm (33x) AB: Nice double star. Brighter component appeared orange, the fainter more bluish.
René Merting
Drachhausen (Germany)
100mm (20x) AB: 20x reicht zwar schon für eine klare Trennung, aber Komponente B im Osten ist nur dumpf grau-blau und noch zu schwach für den schönen Farbkontrast, der sich bei 32x offenbart - Komponente A strahlt dann in einem satten Bernsteingelb, B im Osten gibt sich unterkühlt bläulich - Helligkeitsunterschied 1 bis 1.5 Größenklassen, schwierig abschätzbar wegen der Farben
Robert Zebahl
Leipzig (Germany)
102mm (28x) AB: Splendid view. Primary component clearly orange, secondary blue. ../projects/double-stars/robert-zebahl/sketches/2019-08-22_wz_cas.jpg
Jörg S. Schlimmer
Germany
127mm (136x) Sehr schöner Farbkontrast ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_WZ_Cas_filtered_96dpi.jpg
Mark McCarthy
Fremont (California/USA)
317mm (553x) AB: WZ Cas: Pretty, deep orange A and very wide half delta mag B, white.
René Merting
Drachhausen (Germany)
320mm (45x) AB: bei 45x ein weit getrenntes Pärchen mit wunderschönen Farbkontrast, Komponente A im Westen ist grell-orange und die gut 1.5 Magnituden schwächere Komponente B ist aquamarin-grau
Robert Zebahl
Leipzig (Germany)
102mm ../projects/double-stars/robert-zebahl/photographs/2019-07-16_wz_cas.jpg
★★★ eta Cas, 24 Cas STF60 AB 3m5 7m4 13.4'' 326° 2019 Cas 00h49m06.29s +57°48'54.70"
STF60 AC 3m5 11m4 225.0'' 260° 2000
STF60 AD 3m5 12m8 189.4'' 354° 2011
STF60 AE 3m5 10m2 75.6'' 126° 2015
STF60 AF 3m5 11m5 378.3'' 276° 2000
STF60 AG 3m5 9m5 419.7'' 259° 2012
STF60 AH 3m5 8m4 701.1'' 355° 2012
SMR2 AI 3m5 11m6 90.3'' 73° 2012
SMR2 AJ 3m5 12m3 237.1'' 262° 2012

../images/binary-star-orbits/STF60-AB-orbit.jpg

Robert Zebahl
Leipzig (Germany)
70mm (57x) AB: Easy to split with big difference in brightness. Fainter component appeared deep orange to slightly red colored, brighter component tends to be more slightly yellowish.
René Merting
Drachhausen (Germany)
100mm (32x) AB: bei 32x ist Komponente A so hell, dass B trotz des augenscheinlich großen Abstandes von 13,4" nur knapp getrennt zu sehen ist - Komponente A ist gleißend hell-gelb, B dürfte mindestens 3 Größenklassen schwächer sein und wirkt dadurch dumpfer
Uwe Pilz
Leipzig (Germany)
105mm (53x) AB: leicht
Uwe Pilz
Leipzig (Germany)
105mm (288x) kein Sternentstehungsgebiet! ../projects/double-stars/uwe-pilz/sketches/etaCas.jpg
Sarah Gebauer
Germany
150mm (54x) AB: bei 54x erst nur einen Stern gesehen, doch da, ganz schwach darunter doch die wesentlich schwächere, zweite Komponente entdeckt ../projects/double-stars/sarah-gebauer/sketches/20200731%20Eta%20Cas%20DSk.jpg
Winfried Kräling
Marburg (Germany)
152mm (175x) ../projects/double-stars/winfried-kraeling/sketches/2021-07-23-2055UT-Eta%20Cassiopaia.jpg
Mark McCarthy
Fremont (California/USA)
317mm (553x) AB: Nice yellow pair. A is a red tainted yellow, B is cleaner.
René Merting
Drachhausen (Germany)
320mm (72x) AB: bei 72x ein echt fetter Farbkontrast, Komponente A ist gleißend hell und zitronengelb, B zeigt sich knallig orange - beide Sterne sind gut getrennt voneinander zu beobachten - sehenswert
★★★ S398 AB 6m3 8m0 68.9'' 100° 2018 Psc 01h28m22.92s +07°57'40.90"
Christopher Hay
Seeheim (Germany)
7x50 On tripod. Wide split. A orange-red, B a tiny pinprick of light. Attractive sight in 7.3° field of view, with Zeta Psc neatly on western edge of FOV.
Physical double according to Stelledoppie.
Three-star rating awarded because this is a physical double that can be resolved at 7x, while dominating the field of view with more power and presenting a strong colour contrast with more aperture (see 20x80 observation below). As an added bonus, S398 is just half a degree south of the ecliptic and is thus visited regularly by planets and the moon.
Christopher Hay
Seeheim (Germany)
20x80 Wide split. A reddish-white, B blue-white. Very strong visual presence with no competition in 2.5° field of view, accentuated nicely by 6-mag 96 Psc about 2/3° to the south.
Mark McCarthy
Fremont (California/USA)
317mm (553x) orange with 1 delta mag white to east.
★★★ gamma And, 57 And, Alamak STF205 A-BC 2m3 5m0 9.6'' 63° 2019 And 02h03m53.92s +42°19'47.50"
STT38 BC 5m3 6m5 0.2'' 96° 2010
BAR22 AD 2m3 15m0 27.9'' 245° 1898

../images/binary-star-orbits/STT38-BC-orbit.jpg

Robert Zebahl
Leipzig (Germany)
63mm (42x) A-BC: Easy to split with quite large difference in brightness.
Christopher Hay
Seeheim (Germany)
71mm (32x) Fine split. A is mandarine orange. BC has trouble displaying its colour due to the overpowering light of A, but in good moments is clearly blue.
A-BC is a physical double at a distance to us of 393 light years.
BC is also physical, with a relatively short period of 63 years for C to circle B and a very tight periastron. Unobservable in 2013 at periastron with 0.1". Since then the angular separation has been widening rapidly and will reach 0.4" in 2029. B-C will then become observable in large amateur telescopes for three decades, after which C will fall quickly back to B.
Uwe Pilz
Leipzig (Germany)
105mm (52x) A-BC: einfach
Uwe Pilz
Leipzig (Germany)
120mm (128x) A-BC ../projects/double-stars/uwe-pilz/sketches/201105GammaAnd.jpg
Robert Zebahl
Leipzig (Germany)
152mm (100x) A-BC: Very easy. A: orange, BC: rather white.
Christopher Hay
Seeheim (Germany)
180mm (110x) A very strong pair in 0.6° FOV with powerful colour contrast, A yellow, BC ice blue.
René Merting
Drachhausen (Germany)
320mm (45x) A-BC: bei 45x ein knapp getrenntes Pärchen - Komponente A knallgelb mit einem Anhängsel nordöstlich - Komponente BC strahlt 3 Größenklassen schwächer - bei 144x wirkt BC grün-weiß, bei 45x war der Eindruck noch leicht gelblich
Mark McCarthy
Fremont (California/USA)
508mm (667x) BC: Component of STF 205, of which A is a brilliant orange and BC bright blue. In BC I can only see elongation through the speckle at 667x and 1067x. Short 62.63 year period which will get "easier" to about 0.2" by 2045
Mark McCarthy
Fremont (California/USA)
508mm (1067x) BC: I spent a good long while on this one, and tried hard to nail down the position angle. At 1067x, both with and without an apodising mask, but both times with a #80A light blue filter, which did seem to calm the diffraction a little, I had a clear view of the elongation with a strong sense of the weaker end being to the East or to the ESE. I also tried a 78% central obstruction mask, and while the diffraction became a grid, and the disks much smaller, I could clearly see the same elongation and weaker end, though at a much smaller scale. To my delight the current orbital solution puts the PA at 120.6-degrees, 0.179" separation, so I think I have detected it. I can't wait until 2033 when this becomes an easy pair!
Werner E. Celnik
Rheinberg (Germany)
150mm A-BC ../projects/double-stars/werner-celnik/photographs/GammaAnd%202011-10-31%201800UT%20Refr_150-1100%20DBK21_Col%207ms%205minGIOTTOMittel7500fr%20A10436%20kl.jpg
Winfried Kräling
Marburg (Germany)
127mm A-BC: Aufnahme vom 11.09.2020 am 127/1200mm Refraktor mit Barlowlinse (~2.5x)
Weit getrennt, Komponente A: goldgelb bis orange, Komponente BC: weißlich blau
../projects/double-stars/winfried-kraeling/photographs/2020-09-11-2012UT-Doppelstern-Gamma%20And.jpg
★★★ STF227, iota Tri, 6 Tri 5m3 6m7 3.7'' 69° 2016 Tri 02h12m22.28s +30°18'11.10"

../images/binary-star-orbits/STF227-orbit-solution-1.jpg ../images/binary-star-orbits/STF227-orbit-solution-2.jpg

Robert Zebahl
Leipzig (Germany)
70mm (57x) At 44x even separable with a clear difference in brightness, whereby the companion is almost outshone by the primary component. At 57x easy to separate. Primary component shines in bright orange, companion slightly orange. Beautiful sight together with STF232 in one field of view! ../projects/double-stars/robert-zebahl/sketches/2019-12-12_6_tri_stf232.jpg
Uwe Pilz
Leipzig (Germany)
105mm (88x) weiß und blau ../projects/double-stars/uwe-pilz/sketches/191230stf227.jpg
Christopher Hay
Seeheim (Germany)
180mm (110x) Well separated. Primary yellowish, secondary light blue. When 6 Tri drifts out of 0.6° FOV, STF232 drifts in.
6 Tri is a physical double at a distance to us of 291 light years.
Mark McCarthy
Fremont (California/USA)
203mm (205x) 6 Tri. Yellow A, white b, pretty. Wide, about two delta mag
Frederik Wanink
Itterbeck (Germany)
254mm (200x) Helligkeitsunterschied deutlich
Karsten Kopp
Köln (Germany)
600mm (180x) Doppelstern ist noch gut zu trennen und der Helligkeitsunterschied ist mit gut 1,5 mag schon sehr auffällig. Der hellere Stern erstrahlt schön gelblich, der schwächer weiß. In den Momenten der wirklich ruhigen Luft, ein sehr schöner Doppelstern
★★★ STF231, 66 Cet AB 5m7 7m7 16.8'' 235° 2019 Cet 02h12m47.54s -02°23'37.10"
Christopher Hay
Seeheim (Germany)
30x80 Wide split. A is cream-white, B of indeterminate colour. Attractive pair in 1.7° FOV, scenery accentuated by 63 Psc about 3/4° to northwest.
While pleasant with 30x80, the pair becomes suprisingly difficult to split with 20x80, presumably due to the cumulative effect of 2m delta-mag and the red colour of the companion, which makes it stand out less than if it were blue (colour not seen, but stressed by Uwe Pilz in his 105mm observation, see below).
Uwe Pilz
Leipzig (Germany)
105mm (88x) weiß und leuchtend rot! ../projects/double-stars/uwe-pilz/sketches/191129_66Cet.jpg
★★★ STF232 7m8 7m9 6.7'' 69° 2019 Tri 02h14m42.16s +30°23'41.20"
Robert Zebahl
Leipzig (Germany)
70mm (22x) Very beautiful view! With all used magnifications together with iota Tri (6 Tri) in one field of view. Separable at 22x, but the components are still quite close together and appear similarly bright. At 44x easy to separate with little difference in brightness. At 57x a very small color difference is visible without being able to clearly name the colors. STF232 was sketched together with 6 Tri.
Christopher Hay
Seeheim (Germany)
180mm (110x) Wide separation. Very even brightness. Northeast secondary appears slightly bluish compared to primary.
Mark McCarthy
Fremont (California/USA)
203mm (205x) Pretty white stars, only a slight delta mag, well split
Karsten Kopp
Köln (Germany)
600mm (180x) Doppelstern einfach zu trennen und beide Sterne haben die gleiche Hellgkeit. Da beide weißlich strahlen, habe ich den Eindruck, als würden zwei Scheinwerfer aus dem All in unsere Richtung leuchten.
★★★ STF93, alpha UMi, 1 UMi, Polaris AB 2m0 9m1 18.4'' 236° 2016 UMi 02h31m49.09s +89°15'50.70"
AC 2m0 13m8 39.0'' 103° 2016
AD 2m0 14m3 83.2'' 194° 2016
Christopher Hay
Seeheim (Germany)
71mm (32x) B well separated, a fine blue pinprick next to luminous yellow A.
Alpha UMi, Polaris, is a physical double at a distance to us of 433 light years.
Christopher Hay
Seeheim (Germany)
76mm (40x) B well set off from A. Glare from A is an issue, consciously trying to ignore A helps. Very slight yellowish tone of A. Seeing the difficulty makes it clear why attempts in other nights to split the pair with 25x80 binoculars failed.
René Merting
Drachhausen (Germany)
100mm (32x) AB: bei 32x knallt die Hauptkomponente A schön hellgelb rein, Komponente B ist als feiner zarter Lichtpunkt knapp daneben erkennbar - Größenklassenunterschied nicht abschätzbar, auf jeden Fall riesig
Christopher Hay
Seeheim (Germany)
180mm (113x) B widely separated from A. A has definite yellowish hue. B luminous aquamarine blue, very attractive.
René Merting
Drachhausen (Germany)
320mm (45x) AB: bei 45x ist B sehr knapp getrennt von A erkennbar - Komponente A strahl auf den ersten Blick weiß, bei genauerem Hinsehen mischt sich ein zartes Gelb unter
★★★ STF412, 7 Tau AB 6m6 6m9 0.8'' 351° 2019 Tau 03h34m26.62s +24°27'52.10"
AB-C 5m9 9m9 22.4'' 53° 2014

../images/binary-star-orbits/STF412-AB-orbit.jpg

Uwe Pilz
Leipzig (Germany)
105mm (260x) AB: A-B länglich
Christopher Hay
Seeheim (Germany)
180mm (110x) No definite elongation of AB seen at 110x, seeing is poor. But nice pinprick of light wide off to NE, seems bluish, this is the C component.
AB-C is physical at 429 light years distance from us, and so is A-B, so this is a physical triple system. Very easy to find 3° due west of the Pleiades.
★★★ STF470, 32 Eri AB 4m8 5m9 6.9'' 349° 2019 Eri 03h54m17.49s -02°57'17.00"
Robert Zebahl
Leipzig (Germany)
55mm (27x) At 27x split, but still tight with noticeable difference in brightness. A slight difference in colors could be seen. At 56x the color difference was very evident: The brighter component appeared slightly yellowish, the fainter one slightly bluish. Highly recommended! The sketch was done few days later during another observation. ../projects/double-stars/robert-zebahl/sketches/2019-02-09_32_eri.jpg
Uwe Pilz
Leipzig (Germany)
105mm (288x) Farbkontrast, gelborange-blauweiß ../projects/double-stars/uwe-pilz/sketches/32Eri.jpg
★★★ STFA10, theta 2 Tau, 78 Tau AB 3m4 3m9 347.9'' 339° 2016 Tau 04h28m39.74s +15°52'15.20"
Christopher Hay
Seeheim (Germany)
2x54 Well separated, luminous orange and ice blue. Gorgeous with entire Hyades and Pleiades in 25° field of view.
Theta Tau is a physical double at a distance to us of 150 light years.
Christopher Hay
Seeheim (Germany)
7x45 Theta Tauri. Luminous orange and blue. Wide apart but very much feeling to belong together, despite the many stars of the Hyades all around.
A physical pair. The data suggest separation with naked eye is possible, something to try in good health under a steady sky. At all events with naked eye Theta Tauri is at the centre of the southern stroke of the Hyades' distinctive "V" shape. In the binoculars, by ignoring Aldebaran, which is not a cluster member but a foreground star, it suddenly becomes apparent that Theta Tauri is in fact at the centre of the Hyades in our sky and is its lucida. This impression is supported very nicely by 7x and 8.6° FOV. Definitely one of the finest doubles for this class of binocular.
★★★ STF668, 19 Ori, beta Ori, Rigel A-BC 0m3 6m8 9.7'' 202° 2017 Ori 05h14m32.27s -08°12'05.90"
Robert Zebahl
Leipzig (Germany)
55mm (83x) The second component was immediately seen as faint companion. ../projects/double-stars/robert-zebahl/sketches/2019-01-21_stf668.jpg
Robert Zebahl
Leipzig (Germany)
70mm (67x) First attempt at 133x: much fainter component clearly visible as a tiny star at a relatively large distance. After that the visibility was easy even at 67x. At 44x the faint component could only be guessed.
Robert Zebahl
Leipzig (Germany)
102mm (160x) Much fainter companion immediately visible as tiny star far outside the diffraction pattern of the primary component.
Uwe Pilz
Leipzig (Germany)
105mm (288x) zwei Ringe und zahlreiche radiale Strahlen um den Hauptstern ../projects/double-stars/uwe-pilz/sketches/Rigel.jpg
Jörg S. Schlimmer
Germany
127mm (108x) high contrast ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_Rigel_Refraktor_2021_03_07_bear_filtered_96dpi.jpg
Jörg S. Schlimmer
Germany
305mm (170x) high contrast ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung%20Rigel%20Newton%202021_02_27%20bear_filtered_96dpi.jpg
★★★ Winnecke 2, WNC2 A-BC 6m9 7m0 3.1'' 159° 2019 Ori 05h23m51.32s -00°51'59.80"

../images/binary-star-orbits/WNC2-A-BC-orbit.jpg

Robert Zebahl
Leipzig (Germany)
70mm (44x) Double star appeared elongated.
René Merting
Drachhausen (Germany)
100mm (64x) bei 64x ein extrem eng stehendes wunderschönes Pärchen zweier gleich heller gelber Sterne - keine 8 mehr, beide sind schon getrennt - bei 107x kommt etwas mehr Luft zwischen beide, aber sie scheinen auch ein wenig Farbe zu verlieren
Robert Zebahl
Leipzig (Germany)
120mm (150x) Clearly split with nearly equally bright components.
Mark McCarthy
Fremont (California/USA)
203mm (333x) Nice near equal, light yellow-white stars, well split. nice pair [BC is A 847 7.67/7.84 0.3" and could have been gotten on a better night!]
Mark McCarthy
Fremont (California/USA)
508mm (533x) Easy and obvious pair, bright 7th mag stars ~3". [This was a first try at the short period list but I missed the object, which is A 847 BC, 7.67/7.84 0.3" -- need to try again.]
★★★ theta 1 Ori, Trapezium, 41 Ori AB 6m5 7m5 8.9'' 32° 2019 Ori 05h35m15.82s -05°23'14.30"
AC 6m5 5m1 12.9'' 133° 2019
BD 7m5 6m4 19.4'' 121° 2019
CD 5m1 6m4 13.4'' 62° 2019
AE 6m5 11m1 4.6'' 352° 2013
CF 5m1 11m5 4.7'' 120° 2013
Robert Zebahl
Leipzig (Germany)
16x70 2021-02-24: Components A, C & D are clearly separable from each other. The fainter B component is almost completely outshone by A. The pair AB appears clearly elongated and is with concentrated observation in a few moments even visible separated.
Robert Zebahl
Leipzig (Germany)
70mm (22x) 2021-02-24: The different bright components A-D are clearly visible separated from each other.
Christopher Hay
Seeheim (Germany)
71mm (32x) 13x: CD definitely split, A uncertain, B not present.
18x: A, C and D definite, B uncertain.
32x: A, B, C and D present and clear.
Mediocre seeing but good transparency with strong M42 and an inkling of M43 at 32x. B is an eclipsing variable with a period of 6.5 days and an amplitude of 0.6mag, presumably obervation was at minimum, which would explain the difficulty in seeing it at lowest powers. C is the main source of excitation of the great Orion Nebula M42/43.
Jörg S. Schlimmer
Germany
127mm (108x) A-E split ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung%20Trapez%20Refraktor%202021_02_28%20bear_filtered_96dpi.jpg
Jörg S. Schlimmer
Germany
305mm (170x) A-F split ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung%20Trapez%20Newton%202021_03_02%20bear_filtered_96dpi.jpg
★★★ sigma Ori, 48 Ori BU1032 AB 4m1 5m3 0.3'' 77° 2015 Ori 05h38m44.77s -02°36'00.20"
STF762 AB-C 3m8 8m8 11.4'' 239° 2019
STF762 AB-D 3m8 6m6 12.9'' 84° 2019
STF762 AB-E 3m8 6m3 41.4'' 62° 2019
STF762 DC 6m6 8m8 23.8'' 252° 2019
STF762 EC 6m3 8m8 52.9'' 242° 2019
STF762 ED 6m3 6m6 29.8'' 233° 2019
STF3135 AB-F 3m8 7m9 208.0'' 324° 2016
Christopher Hay
Seeheim (Germany)
10x42 Binoculars with internal stabilisation, handheld.
AB-D: No split, nor any elongation of AB towards D seen.
AB-E: E is set off well from AB but harder to split than the numbers would suggest. This is partly due to the major delta-mag, and partly to the circumstance that D effectively reduces the "free" stretch of sky to 29".
STF761 is a nice complement a few minutes of arc to the west and makes the visual impression of possibly belonging to the Sigma Ori complex, but Stelledoppie doesn't confirm this.
Christopher Hay
Seeheim (Germany)
15x45 Binoculars with internal stabilisation, handheld.
AB-D: No split acheived. However, focussing on AB feels uncertain, presumably due to disturbance by D. Also not split with 15x60 on tripod.
AB-E: E is set off well from AB.
Christopher Hay
Seeheim (Germany)
25x80 AB-D: D is set off nicely from AB and appears very slightly on the orange side, particularly in contrast to E.
René Merting
Drachhausen (Germany)
100mm (64x) AB-C: bei 64x zeigt sich Komponente C ganz schwach südwestlich von AB
AB-D: bei 32x schließt sich an die zartgelbe Komponente AB unmittelbar im Osten dicht stehend D weißorange an - ein schickes Trio zusammen mit E weiter östlich
AB-E: bei 32x zeigt sich in vierfacher Entfernung von AB-D die Komponente E weiter östlich in einer Linie - E ist ähnlich hell wie D
Sarah Gebauer
Germany
150mm (125x) ein sehr schönes Muster des Mehrfachsystems, auch wenn längst nicht alle Komponenten getrennt zu sehen waren, AB-C, AB-D und AB-E getrennt, A und B nicht ../projects/double-stars/sarah-gebauer/sketches/20200409%20Sigma%20Ori%20DSk.jpg
Uwe Pilz
Leipzig (Germany)
320mm (80x) AB-C-D schon im Aufsuchokular sichtbar. Sehr lebhafte Farben, einer der schönsten Mehrfachsterne überhaupt. Im selben Feld mit STF761 ../projects/double-stars/uwe-pilz/sketches/200212sigmaOri.jpg
★★★ 59 Ori H5 100 AB 5m9 10m4 36.7'' 206° 2015 Ori 05h58m24.44s +01°50'13.60"
ARN37 AC 5m9 6m9 177.8'' 293° 2015
Christopher Hay
Seeheim (Germany)
7x45 AC: Handheld: AC wide apart and immediately striking as double star.
On tripod: Wide apart but still very double-star-ish. C appears light blue.
Arnold 37 is a physical double at a distance to us of 364 light years.
Christopher Hay
Seeheim (Germany)
15x45 AC: AC wide apart but holding together visually as strong pair in 4.5° FOV. C distinctly blue, A appears slightly orange in contrast.
★★★ beta Mon, 11 Mon STF919 AB 4m6 5m0 7.1'' 133° 2019 Mon 06h28m49.07s -07°01'59.00"
STF919 AC 4m6 5m4 9.9'' 126° 2019
STF919 BC 5m0 5m3 3.0'' 109° 2019
BU570 AD 4m6 12m1 26.5'' 56° 2014
René Merting
Drachhausen (Germany)
18x70 das Mehrfachsystem ist als 8 erkennbar, eine extrem knappe Berührung, wobei die Komponenten B und C im SO nur als ein Stern gesehen werden können - BC ist gleich hell wie A allein
René Merting
Drachhausen (Germany)
100mm (32x) A-BC: bei 32x ein wunderschöner eng stehender Doppelstern - die bei dieser Vergrößerung noch nicht trennbare Komponenten B und C im SO wirken leicht gelblich und ist leicht heller als A - die Komponenten A und BC wollen sich berühren, schaffen es aber nicht ;-)
BC: bei 64x wirkt BC leicht länglich wie ein Stäbchen - bei 107x dann der Aha-Effekt, es sind zwei Sterne, knapp getrennt und mit gleichem Positionswinkel wie A-BC - beide Komponenten B und C sind gleich hell und einzeln jeweils etwa eine halbe Größenklasse schwächer als A im NW
Uwe Pilz
Leipzig (Germany)
105mm (137x) Dreifachsystem, drei fast gleichhelle Sterne. Alle blau-weiß ../projects/double-stars/uwe-pilz/sketches/betaMon.jpg
★★★ AGC1, 9 CMa, alpha CMa, Sirius AB -1m5 8m4 10.7'' 75° 2016 CMa 06h45m08.92s -16°42'58.00"

../images/binary-star-orbits/AGC1-AB-orbit.jpg

Uwe Pilz
Leipzig (Germany)
105mm (198x) mit ADV, ohne nicht trennbar. Eindeutig
Robert Zebahl
Leipzig (Germany)
120mm (150x) 2021-03-02: Used magnifications from 86x to 200x using a Baader yellow filter. The diffraction disk was relatively good visible, but the diffraction rings were noticeably in movement (Seeing 3/5).
Jörg S. Schlimmer
Germany
127mm (136x) not split ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_Sirius_Refraktor_2021_03_07_bear_filtered_96dpi.jpg
Mark McCarthy
Fremont (California/USA)
203mm (368x) Small disk formed on diffraction spike at correct separation and PA (Feb. 2016)
Mark McCarthy
Fremont (California/USA)
317mm (443x) A faint yellow-orange disk, to the edge of Sirius A's diffraction and just below my spider's diffraction spike. I let Sirius pass beyond the field stop, and for an instant there was Sirius B, clearly separated, before it too passed beyond the field stop.
Jörg S. Schlimmer
Germany
305mm hard to split with CMOS Camera ../projects/double-stars/joerg-schlimmer/photographs/Sirius_20210224_res_best45_bear.jpg
★★★ STF948, 12 Lyn AB 5m4 6m0 1.9'' 64° 2019 Lyn 06h46m14.15s +59°26'30.10"
AC 5m4 7m0 8.9'' 309° 2019

../images/binary-star-orbits/STF948-AB-orbit.jpg

Robert Zebahl
Leipzig (Germany)
55mm (27x) AC: Components A/B and C well separated, but tight. Significant difference in brightness. The fainter C companion appeared slightly orange, the brighter one white-bluish.
Robert Zebahl
Leipzig (Germany)
55mm (167x) AB: Components A and B separated, whereby the Airy disks slightly overlap. The difference in brightness was well visible. ../projects/double-stars/robert-zebahl/sketches/2019-01-21_stf948.jpg
Robert Zebahl
Leipzig (Germany)
63mm (140x) AB: Components A and B split with almost no space in between. The difference in brightness was visible. ../projects/double-stars/robert-zebahl/sketches/2019-01-22_stf948.jpg
Robert Zebahl
Leipzig (Germany)
70mm (22x) AC: Well split, relatively close together with significant difference in brightness.
Robert Zebahl
Leipzig (Germany)
70mm (133x) AB: Both components A + B clearly split, whereby the diffraction rings where merged together. A very nice view together with component C. I sketched this triplet, which reflects my impression well. Unfortunately, the distance and position angle are not particularly well observed. Also the difference in brightness I didn't noticed during my observation. ../projects/double-stars/robert-zebahl/sketches/2019-01-20_stf948.jpg
Robert Zebahl
Leipzig (Germany)
102mm (129x) At 28x the pair AC is nicely separated without any problems. The close pair AB is already recognizable at 86x as a clear figure '8', at 125x wonderfully separated. The components A & B appear yellowish. Very nice view together with STF 946 in one field of view! ../projects/double-stars/robert-zebahl/sketches/2020-03-23_stf946_stf948.jpg
Uwe Pilz
Leipzig (Germany)
105mm (88x) im selben Feld mit STF 946 ../projects/double-stars/uwe-pilz/sketches/200409_12lynstf946.jpg
Robert Zebahl
Leipzig (Germany)
152mm (129x) At 49x the pair AC is beautifully separated with a significant difference in brightness. At 100x, the close pair AB is also separated, although still very close together. A slight difference in brightness is noticeable. At 129x, the view is magnificent. The two bright components A & B present themselves yellowish, the fainter component C rather greyish. STF 948 can be well observed in a field of view with the neighbouring double star STF 946. Both show a nice overall scenery.
★★★ ENG28 AB 7m9 7m7 171.9'' 99° 2015 Gem 07h08m00.24s +15°31'42.90"
Christopher Hay
Seeheim (Germany)
7x45 Handheld. Widely split matched pair. Easy to find half a degree south of 45 Gem. Comfortably viewed in 8.6° FOV together with STTA 80 AB and STF 1007, all three systems well-to-wide split, a charming trio of doubles. Alternatively, ENG 28 can also be viewed together with Zeta Gem (Mekbuda) 5° to the north.
Engelmann 28 is a physical double at a distance to us of 152 light years.
There is an interesting quirk about the ENG designation, on which Stelledoppie notes: Some time after publication of the IDS, the designation for Engelmann was changed from EN to ENG and that for Engelhardt from ENG to ENH. This has led to considerable confusion between the two.
Mark McCarthy
Fremont (California/USA)
80mm (13x) Pretty, wide equal finder split, white, nice field.
★★★ STF1110, alpha Gem, 66 Gem, Castor AB 1m9 3m0 5.5'' 53° 2019 Gem 07h34m35.86s +31°53'17.80"
AC 1m9 9m8 69.8'' 163° 2017
AD 1m9 10m1 179.8'' 221° 2017

../images/binary-star-orbits/STF1110-AB-orbit.jpg

Robert Zebahl
Leipzig (Germany)
55mm (27x) AB: At 27x slight difference in brightness visible. Double star appeared as '8'. At 38x clearly split, but tight.
Robert Zebahl
Leipzig (Germany)
70mm (44x) AB: At 44x the double star appeared as an '8'. At 100x clearly split with noticeable difference in brightness. Both components appeared white.
Christopher Hay
Seeheim (Germany)
76mm (50x) AB, 18 February 2021: At 23x oval-elongated with clear position of component A. At 50x finely split. At 83x best sight with first diffraction rings slightly overlapping. At 100x nice pattern of the Airy disks and the overlapping first and second diffraction rings of both components.
René Merting
Drachhausen (Germany)
100mm (107x) AB: bei 32x wirkt der Stern leicht länglich - bei 107x stehen die beiden Sterne schön eng mit überlagernden Beugungsscheibchen, die Komponenten sind dennoch getrennt erkennbar - Komponente B im Osten ist eine halbe Magnitude schwächer - ganz schwacher Farbkontrast
Uwe Pilz
Leipzig (Germany)
105mm (144x) AB: blauweiß-weiß ../projects/double-stars/uwe-pilz/sketches/Castor.jpg
Winfried Kräling
Marburg (Germany)
127mm (250x) AB: 13.03.2017: Beide Komponenten gelblich mit geringem Helligkeitsunterschied, bereits bei V=60x getrennt. ../projects/double-stars/winfried-kraeling/sketches/170313_02_alpha%20Gem_Castor.jpg
Christopher Hay
Seeheim (Germany)
180mm (200x) AB: Two fat spotlights in space. Component B seems greenish at first sight (using a first-class reflector free of chromatic aberration), and certainly has a different hue than component A. The second diffraction rings of A and B meet.
Frederik Wanink
Itterbeck (Germany)
254mm AB ../projects/double-stars/frederik-wanink/photographs/Castor.jpg
★★★ zeta Cnc, 16 Cnc STF1196 AC 5m3 5m8 6.2'' 62° 2020 Cnc 08h12m12.79s +17°38'51.20"
STF1196 AB-C 4m9 5m8 6.0'' 64° 2020
STF1196 AB 5m3 6m2 1.0'' 2020
HUT1 Ca-Cb 6m2 7m1 0.3'' 32° 2019

../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
Leipzig (Germany)
70mm (133x) 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. ../projects/double-stars/robert-zebahl/sketches/2020-03-24_stf1196.jpg
Christopher Hay
Seeheim (Germany)
71mm (32x) AB-C: Finely split. AB yellowish. Substantial delta-mag.
Robert Zebahl
Leipzig (Germany)
102mm (86x) AB-C: Easy to separate. A: light grey, B: pale orange.
Stefan Loibl
Rosenheim (Germany)
102mm (164x) AB-C clearly split, AB obviously elongated but not split
Uwe Pilz
Leipzig (Germany)
105mm (288x) weißblau-gelb-gelb ../projects/double-stars/uwe-pilz/sketches/zetaCnc.jpg
Robert Zebahl
Leipzig (Germany)
120mm (67x) AB-C: Evident difference in brightness, easy to split. Both components of similar color.
Robert Zebahl
Leipzig (Germany)
120mm (200x) AB: Very tight. The Airy disks were still touching. Slight difference in brightness. Extremely beautiful triple star! ../projects/double-stars/robert-zebahl/sketches/2019-02-24_stf1196.jpg
Winfried Kräling
Marburg (Germany)
127mm (250x) 08.04.2018: Sehr schön, 3-fach Stern, A = weißgelb, B = weißgelb, C = weißgelb ../projects/double-stars/winfried-kraeling/sketches/180408_02_Zeta%20Cnc.jpg
Sarah Gebauer
Germany
150mm (83x) AB-C: bei 83x sind AB-C sauber getrennt, laut Atlas 2020 6,1'' Abstand, die Komponenten A und B mit 1,1'' lassen sich nicht trennen, viele schöne Feldsterne dabei ../projects/double-stars/sarah-gebauer/sketches/20200411%20Zeta%20Cnc%20DSk.jpg
Christopher Hay
Seeheim (Germany)
180mm (200x) AB: Hair-fine split. A and B both yellowish-white. C wide from AB, bluish-white, nice colour contrast to AB.
Frederik Wanink
Itterbeck (Germany)
254mm (200x) AB-C: AB (1,1") nicht bemerkt ../projects/double-stars/frederik-wanink/sketches/STF1196.jpg
Mark McCarthy
Fremont (California/USA)
317mm (553x) Ca-Cb: not quite round, oval/olive shaped. It is the AB-C of STF 1196.
Mark McCarthy
Fremont (California/USA)
317mm (553x) AB: Triple, all near equal magnitude, yellow-white. AB ~0.8", hair split.
Mark McCarthy
Fremont (California/USA)
317mm (553x) AC: Triple, all near equal magnitude, yellow-white. AC ~6", wide split.
Karsten Kopp
Köln (Germany)
600mm (257x) AB: Die Komponenten AB-C bei etwas größerem Helligkeitsunterschied einfach zu trennen und auch schön anzusehen. Sterne erstrahlen weißlich gelb. Komponente AB war nicht zu trennen.
★★★ 11 Hya, epsilon Hya SP1 AB 3m5 5m0 0.2'' 241° 2018 Hya 08h46m46.51s +06°25'07.70"
STF1273 AB-C 3m5 6m7 2.9'' 311° 2020
STF1273 AB-D 3m5 12m5 18.1'' 201° 2017
STF1273 AB-E 3m5 10m8 340.5'' 2015
STF1273 AB-F 3m5 10m4 406.5'' 265° 2015

../images/binary-star-orbits/SP1-AB-orbit.jpg ../images/binary-star-orbits/STF1273-AB-C-orbit.jpg

Robert Zebahl
Leipzig (Germany)
70mm (133x) AB-C: Not split. Although a slight brightening was visible in the first diffraction ring, it could also have come from slight coma of the refractor.
Sarah Gebauer
Germany
100mm (200x) AB-C: ist ein heller Stern vom Hydra-Kopf, nicht zu trennen, vermutlich, weil die Komponente AB zu hell strahlt
Robert Zebahl
Leipzig (Germany)
102mm (160x) AB-C: 2020-03-27: The much fainter companion is well visible as an almost round knot directly at the diffraction ring of the primary component. Very nice sight. The seeing was mediocre (3/5).
Uwe Pilz
Leipzig (Germany)
105mm (200x) AB-C: bei 144x schwierig ../projects/double-stars/uwe-pilz/sketches/200323epsHya.jpg
Robert Zebahl
Leipzig (Germany)
152mm (150x) AB-C: 2020-03-27: The companion is immediately visible as a tiny star close to the primary component. Due to the chromatic aberration of the achromat, there is a slight tendency to outshine. Nevertheless a nice view. The seeing was mediocre (3/5).
Mark McCarthy
Fremont (California/USA)
508mm (533x) AB-C: Epsilon Hya A is bright orange-yellow, B is much fainter and a little blue, ~3". [SP 1 AB is 3.49/5.00 0.2" not seen]
★★★ STF1552, 90 Leo AC 6m3 9m8 63.4'' 235° 2018 Leo 11h34m42.50s +16°47'48.90"
AB 6m3 7m3 3.1'' 209° 2018
Robert Zebahl
Leipzig (Germany)
55mm (42x) AB: A and B very tight and unequal. Much fainter component C very wide apart. All components almost in line. Very nice view. ../projects/double-stars/robert-zebahl/sketches/2019-03-09_90_leo.jpg
Sarah Gebauer
Germany
100mm (136x) lange Zeit nach der ersten Beobachtung nun auch die Komponenten A und B getrennt, was bei 136x gut gelingt ../projects/double-stars/sarah-gebauer/sketches/90%20Leo2.jpg
René Merting
Drachhausen (Germany)
100mm (142x) AB: bei 64x wirken die Komponenten A und B wie eine 8 - bei 142x dann die Gewissheit, B ist jetzt allein erkennbar, vom Positionswinkel südwestlich, aber etwas südlicher als C - Helligkeitsunterschied eine dreiviertel Größenklasse - B wirkt hellorange gegen die weiße Komponente A
AC: bei 32x ist Komponente C ziemlich weit südwestlich von A erkennbar - Helligkeitsunterschied mindestens 2.5 Größenklassen
Uwe Pilz
Leipzig (Germany)
105mm (88x) bläulich und violett ../projects/double-stars/uwe-pilz/sketches/210427_90Leo.jpg
Sarah Gebauer
Germany
150mm (30x) AB: einfach zu trennen, erst bei 83x, dann auch bei 30x, sehr feine Punkte mit sichtbarem Helligkeitsunterschied ../projects/double-stars/sarah-gebauer/sketches/20200415%2090%20Leo%20DSk.jpg
Mark McCarthy
Fremont (California/USA)
317mm (170x) AB: 90 Leonis, a close but easily split pair at 170x, a yellow-white A and a bluish-white B.
Mark McCarthy
Fremont (California/USA)
508mm (333x) AB: 90 Leo. Blazing white pair, ~1 delta mag, ~3"
★★★ SHJ146 AB 7m7 8m7 49.5'' 290° 2017 Vir 12h31m14.61s +01°19'37.00"
René Merting
Drachhausen (Germany)
18x70 Komponente B ist westlich von A erkennbar - Helligkeitsunterschied 1.5 Magnituden - A weiß, B grau - das Sternpaar fällt auf, weil kaum gleichhelle Sterne in der Umgebung stehen
Robert Zebahl
Leipzig (Germany)
70mm (33x) Visible difference in brightness and color. I couldn't precisely define the colors itself, but A appeared rather orange, B rather bluish.
Robert Zebahl
Leipzig (Germany)
102mm (28x) Pretty wide pair with visible difference in brightness and lovely color contrast. A: pale orange, B: light blue.
★★★ STF1670, gamma Vir, 29 Vir, Porrima AB 3m5 3m5 3.0'' 357° 2020 Vir 12h41m39.60s -01°26'57.90"

../images/binary-star-orbits/STF1670-AB-orbit.jpg

Christopher Hay
Seeheim (Germany)
15x60 28 February 2021 at 3" separation: Very slight elongation. PA estimated at 5° (thus only 9° off, which seems fairly precise to me considering the low power of 15x and the minimal elongation, both of which make PA estimation difficult).
Intentionally flashed the eyes on the almost full Moon directly prior to observation in order to enhance acuity. Compared the sight of Porrima repeatedly with that of similarly bright Epsilon Vir (Vindemiatrix) to check whether the elongation is perhaps an artefact of the bincolulars or of my eyes, but no elongation seen there.
Robert Zebahl
Leipzig (Germany)
16x70 2021-05-23: Not even close to appear as a double star. The components are just too bright, the separation too small.
Robert Zebahl
Leipzig (Germany)
55mm (56x) 2019-05-18: At 38x slightly elongated. At 56x touching diffraction disks. At 71x clearly separated with very small gap.
Robert Zebahl
Leipzig (Germany)
70mm (44x) 2021-05-26: At full aperture Porrima appears almost separated at 44x. The two diffraction disks are well visible. At 31x it is difficult to see any elongation at all.
At 40mm aperture Porrima can be seen clearly elongated already at 31x, from 67x it appears as an '8'. At only 22x Porrima is not visible as a double star.
Robert Zebahl
Leipzig (Germany)
70mm (104x) 2019-05-04: At 47x clearly visible as '8', at 73x split with almost touching diffraction disks. At 104x clearly separated, equally bright and pretty close together. The gap was smaller than the diameter of the diffraction disk.
Robert Zebahl
Leipzig (Germany)
102mm (125x) 2019-05-01: Extremely nice double star! Equally bright and relatively close together. Both components appeared yellowish-white.
Uwe Pilz
Leipzig (Germany)
105mm (200x) weiß-weiß, die nördliche Komponente ist eine Winzigkeit heller
Winfried Kräling
Marburg (Germany)
127mm (146x) 21.04.2018: Bei V=100x erscheint dieser orangefarbene Doppelstern bereits als „8“. Bei V=146x ist Porrima voll getrennt. ../projects/double-stars/winfried-kraeling/sketches/180421_03_Gamma%20Vir.jpg
Sarah Gebauer
Germany
150mm (166x) die 2,8'' entfernten Komponenten A und B konnten haarscharf bei 83x und 166x getrennt werden, beide strahlen gleich hell als ganz dichte Glanzpünktchen; Komponenten E und F wurden gesehen, C und D allerdings nicht; bei 83x waren AB ganz knapp nicht mehr voneinander getrennt ../projects/double-stars/sarah-gebauer/sketches/20200416%20Gamma%20Vir%20DSk.jpg
Mark McCarthy
Fremont (California/USA)
317mm (170x) Porrima. Very pretty yellow-white, near equal, close split at 170x. Star disks improved with apodizing mask.
★★★ STF1694 AB 5m3 5m7 21.8'' 324° 2017 Cam 12h49m13.80s +83°24'46.30"
Christopher Hay
Seeheim (Germany)
7x45 Handheld. Very elongated with absolutely clear PA, but hand tremor prevents separation.
Christopher Hay
Seeheim (Germany)
7x50 On tripod. Split with a sliver of black inbetween, with creamy-white components, attractive sight. Dry-frozen night in January, 47° elevation above horizon.
Christopher Hay
Seeheim (Germany)
10x42 Binoculars with internal stabilisation, handheld. Fine split with definite difference in brightness of components.
Christopher Hay
Seeheim (Germany)
15x45 Binoculars with internal stabilisation, handheld. AB cleanly split with distinct difference in magnitudes. Strong visual presence of this physical double is enhanced by the complete lack of visual competition in 4.5° FOV. Interesting to contemplate that in the 9th century AD Struve 1694 was just as close to the celestial north pole as Polaris (also a physical double) is today. Also known as 32H Cam, which comes from the celestial map produced by Johannes Hevelius in the late 17th century.
Christopher Hay
Seeheim (Germany)
25x80 Well apart but by no means falling apart, and totally dominating the 3.2° field of view. Neither component would appear particularly colourful on its own, but viewed together the primary is definitely more on the orange side and the secondary more bluish.
At 25x in 3.2° FOV and with an exit pupil around 3mm making the sky background pitch-black, STF 1694 has such a strong visual impact that it becomes a showpiece specimen of a double star. Three-star rating awarded because of this strong visual presence plus binocular accessibility (see 7x50 observation) plus true physical nature of the double (according to Stelledoppie) plus pole-star role in the Middle Ages.
Robert Zebahl
Leipzig (Germany)
70mm (15x) Easy to split with noticeable angular distance and slight difference in brightness. The faint component tends to be more bluish, the brighter one appeared more light yellowish.
René Merting
Drachhausen (Germany)
100mm (32x) bei 32x strahlen beide Komponenten richtig hell und gut getrennt - leichter Farbkontrast, Komponente A ist leicht gelblich, B wirkt eher unterkühlt
★★★ S656 6m9 7m4 86.2'' 209° 2018 Boo 13h50m23.51s +21°16'35.80"
Christopher Hay
Seeheim (Germany)
7x50 On tripod. Well split. A compact pair directly next to orangish-yellow 6 Boo in a remarkably attractive 7.3° FOV together with widely separated 1 Boo (STF 1772 AD) two degrees southwest plus Eta and Tau Boo about three degrees south.
A physical double at a distance to us of 345 light years. This means that South 656 is not just close to 1 Boo AD in our perspective but also actually in space, making the two pairs one of the finest physical double-doubles in the sky for 7x binoculars.
Robert Zebahl
Leipzig (Germany)
8x40 2020-04-05: Wide, medium bright pair. Primary component appeared slightly orange, the companion greyish. The double star is in close vicinity to the star 6 Boo, which shines in a pale orange.
Christopher Hay
Seeheim (Germany)
15x60 On tripod. Wide split. Primary orangish. Well-matched pair, very striking. Nicely accentuated by yellowish 6 Boo a few arc-minutes to the west.
Robert Zebahl
Leipzig (Germany)
70mm (22x) 2020-04-24: Widely separated with little difference in brightness. Both components appeared slightly yellowish. Standing close to 6 Boo, which also shines in a slight yellow.
★★★ alpha Lib, Zubenelgenubi, Kiffa Australis, Lanx Australis SHJ186 AB 2m7 5m2 231.1'' 314° 2012 Lib 14h50m52.78s -16°02'29.80"
AOT53 AC 2m7 12m5 275.6'' 291° 2000

Component A: 9 Lib, alpha 2 Lib
Component B: 8 Lib, alpha 1 Lib
The standardized name Zubenelgenubi only refers to alpha 2 Lib.

Christopher Hay
Seeheim (Germany)
naked eye AB: Noticed with naked eye and without prior PA knowledge that a secondary was flickering next to Zubenelgenubi. Unexpected and first naked-eye sighting. Checked position with binoculars to be sure. Further naked-eye look at Mizar/Alkor (Zeta UMa) to gauge my momentary acuity and assess the difference to Alpha Lib. Zeta UMa more easily and widely split than ever before, and Alkor appeared for the first time bluish, so this was an exceptional night for naked-eye double-star splitting. Three-star rating awarded because Zubenelgenubi is the second-best naked-eye true-physical double star in the summer sky after Mizar/Alkor.
Christopher Hay
Seeheim (Germany)
10x56 AB: Handheld. A strong, wide pair. Both cold white, the secondary more bluish than the primary.
Delightful in 6.3° FOV together with the "Zub's Hat" (Hay-Merting 9) asterism directly above (north of) the pair, an array of six stars looking very much like a hat or cap on Zubenelgenubi.
Gerd Kohler
Langenzenn (Germany)
254mm (76x) AB: Bläulich-weiß - leicht bläulich.
Gerd Kohler
Langenzenn (Germany)
254mm (76x) AC: Bläulich-weiß - weiß. Sehr schwacher Begleiter.
★★★ mu Boo, 51 Boo, Alkalurops CHR181, mu 1 Boo Aa-Ab 4m3 0.1'' 188° 2012 Boo 15h24m29.54s +37°22'37.10"
STFA28, mu 1 Boo AB 4m3 7m1 109.0'' 172° 2018
STF1938, mu 2 Boo Ba-Bb 7m1 7m6 2.3'' 2019

../images/binary-star-orbits/CHR181-Aa-Ab-orbit.jpg ../images/binary-star-orbits/STF1938-Ba-Bb-orbit.jpg

Christopher Hay
Seeheim (Germany)
7x45 STFA28 (AB): Handheld. Wide split. A compact uneven pair. Component A is bluish-white.
Rather charming in 8.6° FOV with Nu1/2 Boo, which has a gorgeous colour contrast, golden-orange and ice-blue, making it one of the strongest colour-contrast pairs in the sky for binoculars and greatly accentuating the sight of Mu Boo.
In 15x45 binoculars STFA28 AB is very wide, component A bluish-white, B warmer.
Robert Zebahl
Leipzig (Germany)
8x40 STFA28 (AB): Easily split with obvious difference in brightness.
Robert Zebahl
Leipzig (Germany)
16x70 STFA28 (AB): 2021-06-14: Wide, relatively striking pair. Pale yellow & dark orange.
René Merting
Drachhausen (Germany)
16x70 STFA28 (AB): weit getrenntes Pärchen, aufgrund der großen Helligkeitsunterschiedes schöner Farbkontrast - Komponente A im Norden gelblich, B im Süden mehr grau-braun
Robert Zebahl
Leipzig (Germany)
70mm (22x) STFA28 (AB): Evident, very wide apart and unequal. A: white-yellowish, B: grey.
Robert Zebahl
Leipzig (Germany)
102mm (125x) Beautiful view! This triple system includes STFA 28 and STF 1938. ../projects/double-stars/robert-zebahl/sketches/2019-04-04_mu_boo.jpg
Uwe Pilz
Leipzig (Germany)
105mm (288x) ein heller 4m und zwei nahe dunkle 7m, lohnend.
Robert Zebahl
Leipzig (Germany)
120mm (23x) STFA28 (AB): Easy to split with large angular distance and noticeable difference in brightness.
Sarah Gebauer
Germany
150mm (125x) A-BC mit 109'' sind bei 125x sehr weit getrennt, es ist der Ansatz eines engen Doppelsterns zu erkennen, der sich mit 2,2'' Abstand auch bis 250x nicht auftrennen ließ
Christopher Hay
Seeheim (Germany)
180mm (105x) STF1938 (Ba-Bb): At 105x in poor seeing a kissing, evenly matched pair. At 180x clearly split despite the poor seeing, southern component (Ba) seems slightly brighter than Bb.
Mark McCarthy
Fremont (California/USA)
203mm (205x) STFA28 (AB): Bright A star does not seem round. The B star is a tight equal pair, pretty set. [Aa,Ab is CHR 181 0.1", and I'd be shocked if I actually detected it. STFA 28 is technically the bright star and the tight pair, the tight pair is Ba,Bb = STF 1938, 7.09/7.63, 2.2"]
Mark McCarthy
Fremont (California/USA)
203mm (205x) STFA28 (AB): Bright A star does not seem round (CHR181). B star is a tight equal pair (STF1938 Ba-Bb). Pretty set. STFA 28 is technically the bright star and the tight pair
Mark McCarthy
Fremont (California/USA)
203mm (205x) CHR181 (Aa-Ab): Bright A star does not seem round (CHR181). B star is a tight equal pair (STF1938 Ba-Bb). Pretty set. STFA 28 is technically the bright star and the tight pair
Mark McCarthy
Fremont (California/USA)
203mm (205x) STF1938 (Ba-Bb): Bright A star does not seem round (CHR181). B star is a tight equal pair (STF1938 Ba-Bb). Pretty set. STFA 28 is technically the bright star and the tight pair
Frederik Wanink
Itterbeck (Germany)
254mm (640x) STF1938 (Ba-Bb): 3er System, schön ../projects/double-stars/frederik-wanink/sketches/STF1938.jpg
Mark McCarthy
Fremont (California/USA)
317mm (277x) STFA28 (AB): Bright white star with tight yellow pair STF 1938 as its companion.
Mark McCarthy
Fremont (California/USA)
317mm (553x) STFA28 (AB): Striking. Bright star with near equal double STF 1938 paired with it. A star is a spectroscopic binary
Mark McCarthy
Fremont (California/USA)
317mm (553x) STF1938 (Ba-Bb): Near equal close but well split double also paired with STFA28
Karsten Kopp
Köln (Germany)
600mm (257x) Hier handelt es sich um ein Dreifachsternsystem, welches jetzt aber nicht durch eine besondere Färbung der Sterne auffällt. Die A - B/C Komponenten stehen noch sehr weit auseinander, wobei auch die A-Komponente um einiges heller erscheint. Die beiden Komponenten B/C sind wesentlich näher beieinander und unterscheiden sich auch kaum in ihrer Helligkeit. ../projects/double-stars/karsten-kopp/sketches/mu%20Boo.jpg
★★★ rho Oph, 5 Oph H2 19 AB 5m1 5m7 3.0'' 334° 2017 Oph 16h25m35.03s -23°26'47.00"
H2 19 AC 5m1 7m3 149.2'' 2000
H2 19 AD 5m1 6m8 156.4'' 252° 2000
KOU63 CF 5m8 11m7 4.8'' 206° 2000
BU1115 DE 6m8 8m4 0.3'' 196° 2018

../images/binary-star-orbits/H2-19-AB-orbit.jpg ../images/binary-star-orbits/BU1115-DE-orbit.jpg

Stefan Loibl
Rosenheim (Germany)
102mm (102x) AB: possible components (DE) and (CF) already visible at 27x magnification with ca. 2 arcmin distance
★★★ 16/17 Dra STFA30, 16/17 Dra AC 5m4 5m5 90.2'' 193° 2018 Dra 16h36m13.72s +52°55'27.80"
STF2078, 17 Dra AB 5m4 6m4 3.3'' 104° 2018
Christopher Hay
Seeheim (Germany)
3x63 Clean split. Separation is much clearer than that of Nu1/2 Dra (STFA35), which is also in 14° FOV and is hair-fine split.
A physical double at a distance to us of 412 light years.
Christopher Hay
Seeheim (Germany)
7x45 A well split and nicely compact pair. When 16/17 Dra is put at the edge of the 8.6° field of view, Nu1/2 Dra stands at the opposite edge. Their comparison thus suggests itself. 16/17 is somewhat wider than Nu1/2. While the components of Nu1/2 are of equal brightness and whiteness, those of 16/17 display a slight difference in both brightness and colour. 17 (A) first seems bluer than 16 (C), but after 20 seconds this impression flips to C and from then on goes back and forth.
Robert Zebahl
Leipzig (Germany)
55mm (27x) STFA30 (AC): Rather wide pair with almost equal components. C component appeared slightly yellowish-orange.
Robert Zebahl
Leipzig (Germany)
55mm (71x) Grand sight! ../projects/double-stars/robert-zebahl/sketches/2019-05-18_16_17_dra.jpg
Christopher Hay
Seeheim (Germany)
80mm (30x) 16 Dra seems more bluish than 17 Dra, the latter seems slightly yellow in comparison and is distinctly elongated. At 84x 17 Dra is cleanly split and such a delightful view together with 16 Dra that I had no desire to ramp up the magnification. All three stars belong to a physical system.
René Merting
Drachhausen (Germany)
100mm (107x) AB: bei 64x noch ein Stäbchen, bei 107x ist B dann knapp getrennt östlich von A erkennbar - B ist auch noch relativ hell bzw. maximal eine Magnitude schwächer
AC: bei 32x weit auseinander stehend - Komponente C im Süden ist maximal eine viertel Magnitude schwächer - leichter Farbkontrast, A weißgelb und C kühlweiß
Frederik Wanink
Itterbeck (Germany)
254mm (640x) STF2078 (AB): sehr schönes Dreiersystem ../projects/double-stars/frederik-wanink/sketches/17Dra.jpg
★★★ BU628 9m5 9m6 0.6'' 262° 2016 Her 17h18m22.22s +32°39'38.50"

../images/binary-star-orbits/BU628-orbit.jpg

Mark McCarthy
Fremont (California/USA)
508mm (1067x) Wow split clean, amazing. No resolution at 667x but at 1067x two airy disks, sep by half disk, half delta mag. Remarkable
★★★ COU994 9m4 11m2 0.5'' 214° 2011 Her 17h19m44.04s +37°02'37.30"
Mark McCarthy
Fremont (California/USA)
508mm (1067x) At very best moments A presents a perfect disk, and a point resolves within the first faint diffraction ring, very faint and small Amazing.
★★★ A2088 9m9 10m0 0.4'' 2011 Her 17h20m32.37s +47°38'51.50"
Mark McCarthy
Fremont (California/USA)
508mm (1067x) sharp and clean split in best moments, seeing lasts a couple seconds. Otherwise it's touching disks.
★★★ COU1594 10m7 10m6 0.5'' 332° 2010 Her 17h33m59.60s +44°28'45.60"
Mark McCarthy
Fremont (California/USA)
508mm (1067x) Needed to wait for seeing but a very extraordinarily fine point resolves with the best seeing, seems much fainter than data but it's definitely there, a hard point.
★★★ COU1596 9m3 9m3 0.2'' 104° 2007 Her 17h42m14.40s +44°22'59.10"
Mark McCarthy
Fremont (California/USA)
508mm (1067x) Olive to notched at best moments, equal stars
★★★ STF2202, 61 Oph AB 6m1 6m5 20.8'' 93° 2019 Oph 17h44m34.09s +02°34'45.90"
René Merting
Drachhausen (Germany)
8x30 die B-Komponente ist östlich von A erkennbar, lässt sich aber noch nicht trennen - eine klassische Ameise
René Merting
Drachhausen (Germany)
10x50 ein ausgesprochen schönes knapp getrenntes Sternpaar - beide Sterne sind in etwas gleich hell - Komponente B im Osten ist nicht ganz so weiß wie A
René Merting
Drachhausen (Germany)
16x70 ein schön eng stehendes Pärchen, knapp getrennt - Komponente A im Westen ist nur leicht heller als B - beide Komponenten wirken weiß
Uwe Pilz
Leipzig (Germany)
16x70 beide gelb ../projects/double-stars/uwe-pilz/sketches/200725_61Oph.jpg
René Merting
Drachhausen (Germany)
100mm (20x) bei 20x leicht zu trennen - Komponente B im Osten ist nur minimal schwächer (keine halbe Größenklasse, denke ich) - Komponente A stahlt ein wenig wärmer als B
Sarah Gebauer
Germany
150mm (30x) bei geringer Vergrößerung (30x) schon sauber getrennt, beide Sterne wirken gleich groß und gleich hell, ein nettes Pärchen
Sarah Gebauer
Germany
150mm (54x) zwei nicht ganz enge Glanzpünktchen in einer eher uninteressanten Umgebung
Mark McCarthy
Fremont (California/USA)
203mm (667x) Half delta mag wide separation white.
Berthold Fuchs
Wiesbaden (Germany)
130mm easy DS ../projects/double-stars/berthold-fuchs/photographs/61%20Ophiuchi.png
★★★ HU1288 8m3 9m4 0.4'' 163° 2016 Her 17h47m09.16s +15°02'13.80"

../images/binary-star-orbits/HU1288-orbit.jpg

Mark McCarthy
Fremont (California/USA)
508mm (1067x) Awesome! clean split, very clean star images. Split by half disk, half delta mag. very cool great catch! suspected at 667x, ramped up power to 1067x to split.
★★★ S694 6m7 7m3 79.3'' 238° 2018 Oph 17h52m05.20s +01°06'40.30"
Uwe Pilz
Leipzig (Germany)
16x70 gelbweiß und blau; identisch WDS1752+0107 ../projects/double-stars/uwe-pilz/sketches/200725_S694.jpg
★★★ BU641 7m0 8m7 0.8'' 341° 2015 Her 18h21m48.44s +21°30'27.90"
Frederik Wanink
Itterbeck (Germany)
254mm (640x) sehr schwierig ../projects/double-stars/frederik-wanink/sketches/BU641.jpg
Mark McCarthy
Fremont (California/USA)
317mm (553x) Extraordinary! Moderately bright A and very much fainter B, 4-5 delta mag, <1" separation. Seeing needs to still.
Mark McCarthy
Fremont (California/USA)
508mm (533x) V989 Her. Seen as a snowman dot to bright white A @ 333x, split with 533x, inside first diffraction ring. Need A's disk to be perfectly tight for B to resolve with seeing. Very nice. 1" at discovery 1878 with Dearborn 18.5-inch
★★★ epsilon Lyr STFA37 AB-CD 4m7 4m6 209.5'' 172° 2016 Lyr 18h44m20.34s +39°40'12.40"
STFA37 AI 5m2 10m1 149.5'' 137° 2015
STF2382, 4 Lyr, epsilon 1 Lyr AB 5m2 6m1 2.2'' 345° 2019
STF2383, 5 Lyr, epsilon 2 Lyr CD 5m2 5m4 2.4'' 74° 2019

../images/binary-star-orbits/STF2382-AB-orbit-solution-1.jpg ../images/binary-star-orbits/STF2382-AB-orbit-solution-2.jpg ../images/binary-star-orbits/STF2383-CD-orbit.jpg

Christopher Hay
Seeheim (Germany)
naked eye While waiting for Comet Neowise at 3 in the morning in July 2020 surprised myself with my first naked-eye separation of Alpha1 und Alpha2 Capricornis (observing site at 50° northern latitude, Alpha1/2 passing through meridian). Encouraged by this, I lay down and had a close look at Epsilon Lyrae, without really expecting to be able to split it naked-eye, having never succeeded previously. At first Epsilon Lyrae appeared as a very short dash of light. Then the dash resolved into two pinpoints. After 15 years in the hobby and at age 60, at last got Eps Lyr split! No precise prior PA knowledge. After memorising PA as seen naked-eye carefully, confirmed it with binoculars. Eps Lyr is the third-easiest physical double in the (northern hemisphere) summer sky for the naked eye, after Zeta UMa (much easier) und Alpha Lib (marginally easier).
Christopher Hay
Seeheim (Germany)
2x54 AB-CD: Clean split. Actually more pleasant than in 4x10 binoculars, presumably due to more steady handheld view.
Robert Zebahl
Leipzig (Germany)
55mm (59x) STF2382 (AB): At 42x slightly elongated, at 59x elongated and obviously notched.
Robert Zebahl
Leipzig (Germany)
55mm (59x) STF2383 (CD): At 42x clearly elongated, but without any visible notch. At 59x split with touching diffraction disks.
Robert Zebahl
Leipzig (Germany)
70mm (57x) STF2382 (AB): Obviously seen as figure '8'.
Robert Zebahl
Leipzig (Germany)
70mm (57x) STF2383 (CD): Split, but extremely tight with almost touching diffraction disks.
René Merting
Drachhausen (Germany)
76mm (95x) AB-CD: bei 29x schön getrennt erkennbar, ohne dass sich AB und CD schon trennen lassen
AB: bei 57x leicht länglich mit kleiner Einschnürung - bei 95x schön eng getrennt, B nördlich wirkt etwas schwächer- bei 127x wunderschön, das Sternpaar hat zwei Beugungsscheibchen, die wie ein Heiligenschein um die beiden Sterne stehen
CD: bei 57x eine 8 - bei 95x ein schön eng getrenntes Pärchen gleichheller Sterne - bei 127x wunderschön, das Sternpaar hat zwei Beugungsscheibchen, die wie ein Heiligenschein um die beiden Sterne stehen
EF und I: bei 127x sind alle drei Sterne (I 10.1 mag / E 12.3 mag / F 12.7 mag) erkennbar
René Merting
Drachhausen (Germany)
100mm (107x) AB: bei 64x ist das Sternpaar mit leichter Einschnürung und Nord-Süd-Ausdehnung erkennbar - beide Sterne stehen minimal enger zusammen als das südlichere Paar CD - bei 107x knappe Trennung, Komponente B nördlich ist mindestens eine halbe Größenklasse schwächer als A
CD: bei 64x als 8 mit Ost-West-Ausdehnung erkennbar - bei 107x knapp getrennt, beide Komponenten sind etwa gleich hell
Sarah Gebauer
Germany
100mm (136x) ein Test mit dem neuen Refraktor, um einen Vergleich zum 6''-Newton zu ziehen: bei 136x schon astrein getrennt, natürlich ziemlich eng und ganz fein getrennt, aber dennoch ein überraschend positives Ergebnis
Robert Zebahl
Leipzig (Germany)
102mm (125x) Stunning view of the components A-D and I! ../projects/double-stars/robert-zebahl/sketches/2019-06-26_epsilon_lyr.jpg
Uwe Pilz
Leipzig (Germany)
105mm (26x) bei 22x nicht trennbar ../projects/double-stars/uwe-pilz/sketches/epsLyr2.jpg
Jörg S. Schlimmer
Germany
127mm (203x) easy to split ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_Epsilon-Lyrae_ausschnitt_filtered.jpg
Sarah Gebauer
Germany
150mm (250x) August 2019 zum ersten Mal die nah beieinanderstehenden Komponenten sauber getrennt, ein grandioser Doppel-Doppel-Anblick
Winfried Kräling
Marburg (Germany)
152mm (175x) ../projects/double-stars/winfried-kraeling/sketches/2021-07-23-2025UT-Epsilon%20Lyrae.jpg
René Merting
Drachhausen (Germany)
320mm (144x) bei 144x sind die Komponenten von AB und CD gerade so getrennt voneinander erkennbar, sie tanzen wie wild miteinander - mit Arperturmaske und Abblendung auf 120 mm zeigen die vier nun deutlich schwächeren Sterne schöne Beugungsscheibchen und sind besser getrennt voneinander sichtbar
Uwe Pilz
Leipzig (Germany)
320mm (200x) 7 Komponenten!! A-B-C-D-E-F-I ../projects/double-stars/uwe-pilz/sketches/epsLyr.jpg
Berthold Fuchs
Wiesbaden (Germany)
130mm Double-Double ../projects/double-stars/berthold-fuchs/photographs/epsilon%20Lyrae.png
★★★ beta Cyg, 6 Cyg, Albireo, STFA43 AB 3m2 4m7 35.2'' 54° 2019 Cyg 19h30m43.29s +27°57'34.90"
Robert Zebahl
Leipzig (Germany)
8x40 Well split, but I didn't recognised any color.
René Merting
Drachhausen (Germany)
10x50 Komponente A ist gleißend hell und stroh-gelb, Komponente B ist deutlich schwächer leicht abgesetzt von A erkennbar und strahlt eigenartig mint-grün
Christopher Hay
Seeheim (Germany)
12x36 Well split. A golden-red, B cold blue. Gorgeous!
Robert Zebahl
Leipzig (Germany)
16x70 2020-07-06: Bright orange & white-bluish.
Robert Zebahl
Leipzig (Germany)
80mm (25x) One of the most beautiful double stars in the northern hemisphere. Differences in brightness and color (orange-blue) are brilliant! Even under urban conditions with small aperture an enjoyment!
René Merting
Drachhausen (Germany)
100mm (32x) bei 32x stehen beide Sterne weit getrennt - Komponente A mit einem satten zitronen-gelb, Komponente B mit einem leichten Stich ins Blaue
Jörg S. Schlimmer
Germany
127mm (203x) easy to split ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_Albireo_filtered_96dpi_127mm.jpg
Sarah Gebauer
Germany
150mm (116x) Erstbeobachtung August 2019: deutlicher Farbunterschied zwischen blau und sattem Gelb zu sehen
Jörg S. Schlimmer
Germany
305mm (170x) alle Komponenten einfach zu trennen ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_Albireo_filtered_96dpi_305mm.jpg
Werner E. Celnik
Rheinberg (Germany)
150mm ../projects/double-stars/werner-celnik/photographs/Albireo%202015-09-09%20Refr_150-1100%205DMkII%20ISO1600%20IDAS%20HDR_1s-2min%20kl.jpg ../projects/double-stars/werner-celnik/photographs/Albireo%202015-09-09%20Refr_150-1100%205DMkII%20ISO1600%20IDAS%20HDR_1s-2min%20cr%20kl.jpg
Werner E. Celnik
Rheinberg (Germany)
150mm ../projects/double-stars/werner-celnik/photographs/Albireo%20A9918-9920%20RGB%20A4%20mTxt%20kl.jpg
★★★ HN 84, V340 Sge 6m4 9m5 28.4'' 301° 2013 Sge 19h39m25.33s +16°34'16.00"
René Merting
Drachhausen (Germany)
12x50 verdammt schwer - Komponente B ist ganz schwach nordwestlich von A auszumachen - beide Sterne berühren sich noch
René Merting
Drachhausen (Germany)
16x70 beide Sterne präsentieren sich gut getrennt, nicht zu weit aber auch nicht zu nah - Komponente A meint es gut mit der Farbe gelb, bei Komponente B kann ich keine Farbe erkennen
Christopher Hay
Seeheim (Germany)
80mm (30x) Primary ruddy red, secondary wide apart but too faint for any colour impression. Straw-yellow Epsilon Saggitae half a degree to the west with its ice-blue eastern companion enhances the experience of colour contrast in the FOV and is actually more attractive than HN 84 with this aperture and power.
René Merting
Drachhausen (Germany)
100mm (20x) bei 20x sind beide Komponenten weit getrennt - Komponente A auffällig gelb-orange, B dagegen grau-blau, ein schöner Farbkontrast, der sich bei 32x verstärkt
Sarah Gebauer
Germany
150mm (85x) Holden 84, eine sehr goldgelbe Komponente und in 28'' Abstand die zweite, sehr schwache und weiße Komponente mit einem Hauch von Blau, sehr, sehr schön!
Christopher Hay
Seeheim (Germany)
150mm (96x) Main component ruddy tangerine orange, companion wide apart and ice blue. The longer I look the stronger the colour contrast becomes, which is by no means normal in many doubles. Epsilon Saggitae in same 0.8-degree field of view is straw-yellow with a cold blue companion (a field star?) pointing away from Epsilon in the direction of HN 84. I can’t think offhand of a better colour-contrast pair that can be framed in this manner in the same FOV.
Sarah Gebauer
Germany
150mm (160x) die hellere Hauptkomponente ist deutlich und stark goldfarben, die zweite dagegen sehr schwach, silbrig und dumpf ../projects/double-stars/sarah-gebauer/sketches/HN84.jpg
★★★ STFA50, omicron Cyg, 30/31 Cyg AD 3m9 4m8 336.7'' 322° 2016 Cyg 20h13m37.90s +46°44'28.80"
AC 3m9 7m0 108.6'' 173° 2016
Robert Zebahl
Leipzig (Germany)
naked eye AD: Well split with noticeable difference in brightness.
Christopher Hay
Seeheim (Germany)
3x63 Self-built binoculars, hence the unusual specification.
Widely split, A (31 Cyg) light orange, D (30 Cyg) light blue.
Christopher Hay
Seeheim (Germany)
7x50 A-D: Widely split, A (31 Cyg) luminous orange-red, D (30 Cyg) luminous ice-blue. C set off from A as a fine speck of light.
Robert Zebahl
Leipzig (Germany)
8x40 AD: Wonderful double star for binoculars. Large distance of the components, brighter once (31 Cyg) appeared slightly orange, the fainter (Cyg 30) more bluish.
Robert Zebahl
Leipzig (Germany)
8x40 AC: Observation at full moon. Easily split with big difference in brightness. Brighter component slightly orange. C component rather faint.
Christopher Hay
Seeheim (Germany)
15x45 A-D: Very wide apart but still perceived as belonging together. A (31 Cyg) orange-red, D (30 Cyg) ice-blue. C well set off from A and light ice-blue, like an echo of D. A delightful group of three for binoculars at this power, further accentuated by nearby orange Omicron2 Cygni. Both the brightnesses and colour hues of Omi1A and Omi2 appear practically identical.
Robert Zebahl
Leipzig (Germany)
16x70 2020-07-03: Fantastic sight. A: bright orange, D: white-bluish, C: light blue. Very beautiful field.
René Merting
Drachhausen (Germany)
18x70 wunderschön - Komponente A präsentiert sich buttergelb - die südliche, schwächste Komponente C zeigt sich aquamarinblau - D im Norden ist reinweiß und steht dreimal weitere entfernt wie AC
Robert Zebahl
Leipzig (Germany)
80mm (25x) AC: Similar to the observation with binoculars. C component appeared bluish and gave good contrast to the orange colored 31 Cyg.
René Merting
Drachhausen (Germany)
100mm (32x) bei 32x sind alle drei Sterne weit getrennt und doch irgendwie zusammengehörend, Komponente A ist rapsgelb und am auffälligsten, Komponente D strahlt weiß und die schwächste Komponente C schimmert bläulich, schöner Anblick
Robert Zebahl
Leipzig (Germany)
102mm (28x) Bright, wide apart and wonderful contrast in color. A: light yellowish-orange, C: blue, D: light blue. ../projects/double-stars/robert-zebahl/sketches/2019-08-22_omicron_cyg.jpg
Sarah Gebauer
Germany
150mm (30x) die drei Komponenten plus Omicron2 bilden ein wunderschönes, sehr langes und spitzes Dreieck und zeigen dabei wundervolle Farben, Komponente A von o1 sowie o2 erscheinen schön gelblich, Komponente D von o1 hat einen deutlichen Blaustich im Weißen, wirklich ein sehr schönes Gesamtbild - auf Komponente C hatte ich nicht geachtet ../projects/double-stars/sarah-gebauer/sketches/20200731%20Omicron%20Cyg%20DSk.jpg
Sarah Gebauer
Germany
150mm (85x) dieses Mal nur die drei dicht beieinanderstehenden Komponenten A, C und D im Sichtfeld gehabt, Komponente A ist wieder deutlich gelbgold, C wirkt leicht bläulich und Komponente D wirkt dieses Mal eher weiß ../projects/double-stars/sarah-gebauer/sketches/20200805%20Omicron%20Cyg%20DSk.jpg
★★★ BLL49, U Cyg 8m0 9m0 65.4'' 231° 2015 Cyg 20h19m41.66s +47°54'19.90"
Robert Zebahl
Leipzig (Germany)
16x70 2020-07-03: Easy split with very good color contrast: white and clear orange.
Robert Zebahl
Leipzig (Germany)
102mm (28x) 2019-08-22: While the primary component appears quite unspectacular in a white, the companion U Cygni is much more interesting. It is a carbon star whose brightness varies between 5m9 and 12m1 with a period of about 463 days. It appears in mostly intensely orange, and even deep red in the towards its minimum. Extremely rewarding! ../projects/double-stars/robert-zebahl/sketches/2019-08-22_u_cyg.jpg
★★★ STF2742 7m4 7m6 2.9'' 215° 2017 Equ 21h02m12.51s +07°10'47.30"
Robert Zebahl
Leipzig (Germany)
70mm (57x) At 44x almost split with slight difference in brightness. At 57x split, but tight.
René Merting
Drachhausen (Germany)
100mm (64x) ähnlich wie STF2765 und STF2786 weiter nördlich wieder so ein knappes Pärchen bei 64x, das scheint Sternbild-typisch zu sein - beide Sterne sind fast gleich hell, der Stern im NO ist minimal heller
Uwe Pilz
Leipzig (Germany)
105mm (94x) Prachtstück! Weiß-Weißgelb. ../projects/double-stars/uwe-pilz/sketches/190930STF2742.jpg
Mark McCarthy
Fremont (California/USA)
317mm (553x) equal light orange, well split, pretty
★★★ STF2758, 61 Cyg AB 5m2 6m0 31.8'' 153° 2019 Cyg 21h06m53.95s +38°44'57.90"

../images/binary-star-orbits/STF2758-AB-orbit.jpg

Christopher Hay
Seeheim (Germany)
8x42 On tripod. Clearly split, northern component A substantially brighter than B. Both orange, whereby A is distinctly more yellowish than B (sky quality similar to that of earlier 15x45 and 10x42 observations). Also seems to be split using the 8x42 handheld, but hand tremor makes this uncertain.
Christopher Hay
Seeheim (Germany)
15x45 Clear to wide separation. Both components of orange hue. Brighter northern component seemed to go slightly into yellow. In 10x42 also clearly split, northern component of orange hue, southern component of indeterminate colour (sky not quite dark enough at the time to see 61 Cyg naked-eye). Piazzi’s Flying Star, flying more than 5” per year to the northeast, and a true physical double with a period of 678 years.
Robert Zebahl
Leipzig (Germany)
16x70 2021-06-14: Beautiful sight. Bright orange & orange.
René Merting
Drachhausen (Germany)
100mm (32x) bei 32x sind beide Sterne gut getrennt, Komponente A strahlt in einem schmutzig dunklem gelb, schwächere Komponente B leicht orange
Uwe Pilz
Leipzig (Germany)
105mm (200x) gelb und orange. Der weitere Stern im Bild ist TYC 3168-6781 ../projects/double-stars/uwe-pilz/sketches/191023_61Cygni.jpg
Uwe Pilz
Leipzig (Germany)
105mm (200x) TYC 3168-5901 kann dazu dienen, den sich ändernden Positionswinkel abzuschätzen. ../projects/double-stars/uwe-pilz/sketches/180901_61Cyg.jpg
Jörg S. Schlimmer
Germany
127mm (203x) Intensive Farbe ../projects/double-stars/joerg-schlimmer/sketches/Zeichnung_61_Cyg_filtered_96dpi.jpg
Robert Zebahl
Leipzig (Germany)
152mm (22x) 2020-06-24: Beautifully separated, bright, striking, especially the colors: bright orange and orange.
Mark McCarthy
Fremont (California/USA)
203mm (121x) 61 Cyg. Nice near equal wide orange pair, bright [18 stars in system -- if so should be an OC]
Berthold Fuchs
Wiesbaden (Germany)
130mm easy DS ../projects/double-stars/berthold-fuchs/photographs/61%20Cygni.png
★★★ BVD142 & TDT3916 BVD142 AB 7m8 10m3 80.0'' 165° 2018 And 23h10m29.28s +41°19'18.70"
TDT3916 Ba-Bb 10m7 11m4 0.6'' 89° 1991
Mark McCarthy
Fremont (California/USA)
317mm (553x) BVD142 (AB): Orange stars, 1 delta mag, well separated (finder split). B looks suspiciously like a pair -- but the transparency may be causing it to smear. This is quite an amazing catch considering the conditions! AB is as described 7.80/10.28 79.6". B is indeed a pair: TDT 3916 = BaBb, 10.69/11.41 0.6". Discovered in 1991 and only one observation!
Mark McCarthy
Fremont (California/USA)
317mm (553x) TDT3916 (Ba-Bb): Orange stars, 1 delta mag, well separated (finder split). B looks suspiciously like a pair -- but the transparency may be causing it to smear. This is quite an amazing catch considering the conditions! AB is as described 7.80/10.28 79.6". B is indeed a pair: TDT 3916 = BaBb, 10.69/11.41 0.6". Discovered in 1991 and only one observation!