| Star Designation | Primary | Companion | Separation | Comments |
| β Monocerotis | 4.6 | 5.4 | 10" | Really this is a triple star but at 37x with my 8" f/6 reflector I saw only two nearly equal white stars very close together; beautiful even without seeing the third component! As an aid in identifying this star, in a low power eyepiece, it makes an obtuse angle with two dimmer stars which present similarly to Arcturus and the two stars that make the shallow angle with it. If you don't see that, you aren't looking at β Monocerotis LOL. In my 6" f/5 achromat at 112x, the triple nature of the star becomes evident. |
| k Puppis | 4.5 | 4.7 | 10" | This is located just east of η Canis Majoris (Aludra), the second and brightest star in a curving arc of 3 stars running east-northeast of Aludra. It appears like two very close identical white stars at 37x in the 8" reflector, quite similar to θ Serpentis. k Puppis is separated by 10". |
| 2 Puppis | 6.1 | 6.8 | 17" | Located just east of M46, there are two stars fairly close together, one dimmer and closer to M46, the other brighter and slightly farther away. The dimmer one is 2 Puppis, a beautiful, slightly unequal pair separated by 17". |
| 32 Camelopardalis | 5.3 | 5.9 | 22" | This is a real treat, two nearly equal white stars that can be split in 20x80 binoculars (I was not able to split them in my 10x50's), and looks great at low power in any scope. They are listed as being approximately 22" apart. Can be difficult to find in an equatorially mounted scope because they are so close to Polaris; It is the brightest star in the shallow bowl made by the arc of stars in Ursa Minor (using Polaris and the next two stars in UMi, find the brightest star at a point in very shallow focus of the bowl). |
| η Persei | 3.8 | 8.5 | 31" | This is a nice unequal pair with strong colors at a separation of 31". It is located at the tip of the northwestern end of Perseus, so it's easy peasy to find. I was able to split it with 37x in my 8" f/6 reflector, but it does require some aperture or magnification because the fainter companion is only magnitude 8.5 (scroll down near the bottom of the above link to find the discussion of this and the next star). |
| θ Persei | 4.2 | 10.3 | 20" | Also a very uneven double, and separated by 20" so some aperture and/or magnification is needed to see the magnitude 10.3 secondary star. More details about this on Jim Kaler's website. |
| η Cassiopeiae | 3.5 | 7.0 | 13" | I look at this one almost every time I take a scope out to look at double stars; Located between the middle star and the next one down to the southwest, it's an uneven pair with a separation of about 13". I don't recall detecting much color in this pair. A significant fraction of one entire orbit of these stars has occurred since their discovery in 1779 by William Herschel. |
| θ Serpentis (Alya) | 4.6 | 4.9 | 22" | This pair looks like 32 Cam and other nearly equal bright white stars, a beautiful sight in any telescope at low power; can be hard to find because even though you know it's the last star in the Serpens (Cauda) chain between Ophiuchus and Aquila, enough bright stars are in this region that it can be easy to mistake others for it until you check it in the eyepiece and see that the candidates are not double, so you have to go on to another one in the area. I have split this in my 20x80 binoculars. |
| h3945 in Canis Major | 5.0 | 5.9 | 27" | Referred to as the "winter Albireo" because of its beautiful color contrast just like Albireo, and generous separation of about 27". It is located in southeastern Canis Major, up a chain of moderately bright stars from the upper star in the hindlegs of the dog, δ Canis Majoris (or Wezen) to the east northeast. To starhop from Wezen, there are two equally bright stars directly to Wezen's east, then go northeast the same distance to another slightly closer pair of stars, then about the same distance north and slightly west to get to h3945. |
| γ Andromedae (Almach) | 2.3 | 5.1 | 10" | Beautiful color contrast, but requires good seeing and some magnification to bring it out. This star is a cinch to locate, it's at the end of Andromeda, done. |
| Antares | 1.0 | 5.4 | 2.5" | I've only split this star one time, in 2018 with my C8 and a 120mm f/8.3 achromat, under excellent seeing conditions, but my observations matched the descriptions of the orientation of the secondary relative to the primary, so I conclude that was successful in resolving it. |
| 54 Leonis | 4.5 | 6.3 | 6" | This is a tough uneven pair only 6.6" apart (scroll down about half-way through the page at the above link to find Star-Splitters' description). They supposedly have a nice color contrast but I don't think I've ever detected that for myself. Michael Vlasov apparently hasn't either! |
| 15 Aquilae | 5.5 | 7.0 | 38" | Nice wide double in the tail of Aquila, the star adjacent to the brightest one of the group (λ Aquilae) to the northwest as seen in the finder chart. Catalogued as being 39" apart, and mildly unequal, so its a great target for low power or even steadily mounted binoculars. |
| ζ Piscium | 5.6 | 6.5 | 23" | This one is easy to find because it's the fourth star after Alrischa along the way toward the Circlet, and because it's a nice low power object, very easy for a casual glance. |
| ξ Cephei | 4.8 | 6.3 | 8" | This is a nice double star that doesn't get much attention, but very rewarding nonetheless. It's easy to locate, being the brightest star in the center of the "box" of Cepheus. They both look white to me. |
| δ Cephei | 3.5 - 4.4 | 6.3 | 41" | Beautiful color contrast and generous separation make this a great object for low power observing; easy to find in the little triangle of stars that make up one of the corners of the box of Cepheus. |
| 41 Aquarii | 5.7 | 7.2 | 5" | This star is the second star off to the right of the Helix Nebula, one over and then up slightly and more to the right. Pretty tight pair and not very bright so you need decent power to see it well. Easy to find, since I often check in on the Helix as a test of transparency, so I am familiar with the pattern. |
| ι Cancri | 4.1 | 6.6 | 31" | Very nice color contrast, earning it the nickname "the spring Albireo", easy at very low power. It's also easy to find, just start at the eastern side of the Beehive cluster (M44) and go north until you find a moderately bright star, the brightest one you will come across; in the finder scope field, there will also be a very wide naked-eye or binocular double star near it. |
| ζ Cancri | 5.4 | 6.0 | 6" | Zeta Cancri is due west of the Beehive cluster (M44), the brightest star in its part of the sky. I have only ever noticed its duplicity, but according to this source, the main component is itself double, separated by approximately 1", something I must try to observe soon with my longish refractor or the 8" f/6 reflector. |
| Castor | 1.9 | 3.0 | 4" | Showpiece double, both white, noticeably unequal, they're so bright that you need good seeing or some haze in the sky, which often times can be the same thing to see them well. |
| 20 Geminorum | 6.3 | 6.9 | 20" | One of my favorites to see in the area of Gemini because I stumbled across this star years ago while sweeping with my newly-acquired refractor. The components are both whitish, with enough magnitude difference to make them interesting, and by enough separation to make them easy at low power. The picture in the link to the left is from the Bedford Catalog. Go about 2/3 of the way down from ν Geminorum to γ Gem to find 20. |
| γ Arietis | 4.5 | 4.6 | 7.5" | Great sight at medium power, two virtually identical white beacons staring at you from out in space, just dazzling! |
| ο Ophiuchi | 6.0 | 7.0 | 11" | This star is located in far southern Ophiuchus, east of Antares, as part of the "arrow-head" grouping anchored on θ Oph at bottom and ξ Oph at the top; this double is the star to the right (west) of θ, so it's very easy to find. An added bonus is a fairly bright star just to the north of omicron that complements the overall scene very nicely. |
| ζ Aquarii | 4.3 | 4.5 | 2.2" | Must have high magnification to make this split, but very rewarding! Beautiful pair of nearly identical stars separated by only a hair's breadth. |
| 107 Aquarii | 5.7 | 6.7 | 7" | This is a nice fairly tight double star in southeastern Aquarius, embedded in one of those neat little star chains common to this part of the constellation. |
| Mizar | 2.2 | 3.9 | 14" | Great looking double star, made more interesting by the addition of Alcor and Sidus Ludoviciana in between them. Their degree of unequalness and fairly tight separation makes for a beautiful view at low power. |
| α Herculis (Rasalgethi) | 3.4 | 5.3 | 4" | Beautiful color contrast, but requires high power to split successfully and appreciate the nice colors. Easy to find just to the west of Rasalhague, the brightest star of Ophiuchus and in the area. While there, don't forget to appreciate the long curving chain of stars ending in a box, below Rasalgethi, known as the sweat of Hercules :) |
| α Piscium | 4.1 | 5.2 | 1.7" | Very close double star of noticeably unequal members that is easy to located since it's at the ending intersection of the two strands of Pisces; you can tell that you're looking at it in binoculars or a low power telescopic view if you see this pattern of three stars in a line next to Alrischa. I've been able to split it in my C8 when the seeing was very good, but of course there were lots of Airy disk ring artifacts with the C8. |
| Albireo | 3.1 | 5.1 | 34" | This must be the most favoritist double star of all, in other words if everyone listed their favorite double star, my guess is Albireo would have the most votes. Beautiful color contrast, easy to split, don't use too much magnification because then the stars are too far apart to appreciate the color contrast. Easily locatable at the opposite end of Cygnus from Deneb. |
| β Scorpii (Graffias) | 2.6 | 4.5 | 13" | Easy to find as the top star in the group of three that make up the head of Scorpius; good magnitude difference and generous separation make it a great low to medium power pair without being too far apart that they don't look good. |
| ν Scorpii | 4.2 | 6.6 | 41" | In the same low power field as β Scorpii, ν is wider and in face splittable in binoculars if you can hold them steady. Quite a bit different in brightness, so they are easy to distinguish and make a very pleasing sight. Having ω1 and ω2 in the same binocular or very low power field of view as ν and β make the entire area a very interesting region of the sky to observe. |
| Algeiba | 2.4 | 3.6 | 4.6" | Easily locatable close double star in the sickle of Leo; great test for medium to high power without being so close that you have to have perfect seeing to catch it like Izar or γ Ceti. I don't see much of a color difference in this pair. |
| Cor Caroli | 2.9 | 5.6 | 20" | This double star is the brightest star in the region of the sky below the handle of the Big Dipper and Arcturus. It has a wide enough separation and great enough magnitude difference to be easily split at low power but also interesting to observe. |
| ν Draconis | 4.9 | 4.9 | 62" | Great binocular double star as long as you can hold them steady, or better yet mount them on a tripod or otherwise stabilize them; two identical white points of light nicely separated make for a wonderful view. Easy to locate this double star since it's the dimmest star of the "lozenge" ~ the head of Draco. |
| Rigel | 0.1 | 6.7 | 9" | Great example of a fairly close double with a huge brightness difference that makes it difficult to pick the secondary out of the primary's glare or diffraction spikes; I've often been able to split Rigel but never Sirius, at least to a degree that I can say was unambiguous. |
| Polaris | 2.1 | 9.0 | 19" | Polaris is a very nice example of a tremendous difference in magnitude, but with enough separation that you can still make it out easily so long as the conditions are decent and you have 4" of aperture or more. |
| β Lyrae | 3.5 | 7.1 | 46" | Nice double star for low power or very steadily mounted binoculars, and if you have enough aperture there are two 10th magnitude components opposite of the secondary from the primary, which make for a very nice overall impression. Easy to locate at the northwest end of the two stars that bookend the Ring Nebula, M57. |
| ζ Lyrae | 4.3 | 5.7 | 44" | Nice double star for low power or steadily held binoculars, very easy to locate just to the south of Vega, at the opposite corner of the triangle from ε Lyrae. |
| γ Delphini | 4.3 | 5.1 | 9" | Very nice double that is easily separable with medium power and doesn't require great seeing, also easy to locate at the top left corner of the diamond of Delphinus. Not easy to detect much color in this binary by me, although the usual descriptions make them seem like they are both yellow. |
| 61 Cygni | 5.2 | 6.0 | 31" | This star is a nice wide double at low power but can be difficult to locate since it's not bright but in a region of many other brighter stars; I always make a parallelogram out of the stars Deneb, Sadr, ε Cygni, and 61 Cygni, and hope I land on it. It's sort of on a line between τ and ν Cygni. |
| δ Orionis (Mintaka) | 2.3 | 6.8 | 52" | Very significant magnitude difference but large enough separation that it can be resolved at low power and in relatively poor seeing as well. Nice view whenver you have time for a quick peek at Orion's belt. |
| ζ Orionis (Alnitak) | 1.9 | 3.7 | 2" | The other side of the belt is much more difficult, requiring high power and good seeing to resolve; fortunately, the magnitude difference of these two stars is not as great as Rigel or Adhara, so the close separation is more easily overcome with Alnitak. |
| ε Boötis (Izar) | 2.6 | 4.8 | 3" | Very difficult split owing to the magnitude difference but very nice color contrast if you can split it; easy to find in the main outline of Boötes, north-northeast of Arcturus. |
| γ Ceti | 3.6 | 6.2 | 2.3" | Very easy to find this double star, at the base of the head/neck of Cetus, just west of Menkar. Tough split owing to the magnitude difference and very close separation, so it requires high power and steady seeing, but beautiful color contrast between the two components. Almost exactly the same declination as α Piscium, so it's easy to swing between the two. |
SAO 59230 in Auriga |
6.7 | 9.0 | 43" | This multiple star is one I stumbled across while hunting for the carbon star UU Aurigae. It's located just to the southwest of UU and is actually a very symmetrical triple star (I don't know if they are physically related of course) but they make a very neat triangle of stars of unequal brightness. The third component is magnitude 9.8 and lies 34" away from the dimmer of the other two, and 46" away from the brighter of them. The trio forms an almost perfect isoceles triangle. |
SAO 58905 in Auriga |
6.9 | 7.5 | 11" | This star is just to the east southeast of θ Aurigae, and based on the view through my 6" f/5 achromat at 37x under bright moonlight, appears to be a very nice double star of almost equal components; my planetarium software TheSky® plots it as a triple star with the dimmest component half-way between the two main components, almost on a line. I could not make out the third component even at 112x, but that could easily be due to the bright sky background. The third component is magnitude 9.4 and lies 5" away from the brighter of the other two, and 7" away from the other one. |
| ι Boötis | 4.8 | 8.2 | 38" | Great low power double in northern Boötes, nice color contrast. |
| κ Boötis | 4.5 | 6.6 | 13" | Great medium power double in northern Boötes, nice color contrast, for some reason the brighter of the two is called κ2 while the dimmer one is κ1 (maybe because of the right ascension?). |
| π Boötis | 4.9 | 5.8 | 5" | Great medium to high power double in southeastern Boötes, easily found to the east of Arcturus among a distinctive binocular grouping of three stars (π, ο and ζ). |
| Σ 1835 | 5.1 | 7.6 | 6" | Neat double star in far southern Boötes, the northernmost and brightest of a cool little string of three stars that curve and exhibit a nice magnitude increase to match the arc shape. |
Double Stars by Constellation