Category Archives: Double/Multiple Stars

Struve 2840: An Easy to See Blue and White Pair in Cepheus

The double star Struve 2840 is located in the northern sky within the constellation Cepheus. Backyard astronomers should find it pretty easy to separate Struve 2840’s two stars, which are separated by 18 arcseconds. The pair is also known as STF 2840, SAO 33819, HD 208063, HR 8357.

Kappa Cephei: A Cosmic Dance Between a Bright and Dim Star

Kappa Cephei, also known as κ Cep and SAO 9665, is a binary star located in the Cepheus constellation. This pair is a tight, but pretty double viewed through a telescope and a good target for backyard astronomers. This system, discovered in 1782, is especially appealing because one star is brighter than the other. Learn about this autumn gem and what you can expect to see through your telescope.

Omicron Cephei: A Challenging but Rewarding Pair in Cepheus

Omicron Cephei, a binary star system situated in the northern sky in the constellation, Cepheus, consists of two contrasting stars; an F-type primary star and a G-type giant companion. This pair’s binary nature was first noted in 1832, and it lies 203 light years away, requiring a moderately-sized telescope for viewing. The binary is also known as SAO 20554, Struve STF 3001, HIP 115088.

Struve 700 (V1804 Orionis): Double Blue in Orion’s Winter Cool

Learn about the double star in Orion called Struve 700 and V1804 Orionis. The pretty set of blue-white stars shine around 7.8 magnitude and are a tight pair in telescope. My sketch shows what the binary looks like through a backyard telescope. They are a great pair to seek out when observing through Orion, the hunter, on winter days.

Struve 2816 and 2819: A Fantastic Double & Triple Set of Stars in Cepheus

Struve 2816 and 2819 make their home in the constellation Cepheus. This much-loved autumn constellation boasts several remarkable celestial objects.

Sketch of Struve 2816 and Struve 2819 as shown in the same 12mm eyepiece in a 8-inch SCT scope. Both sets of double and triple stars are beautiful in the constellation Cepheus. The drawing shows both sets of star also known as STF 2819 and 2816. Also go by (SAO 33626, HD 206267, HR 8281) and (SAO 33652, HD 206482)

Struve 2404: A Tight, Attractive Orange-Red and Yellow Double in Aquila

Struve 2404 is a tight attractive double star in the summer constellation of Aquila, which lies on the celestial equator. The Russian astronomer Otto Wilhelm von Struve first recorded an observation of this pair in 1822.

This pair features a magnitude +6.9 primary star with a beautiful warm orange hue. The orange-red giant star has a stellar classification of K5III and is nearly 60 times the diameter of our sun! The secondary star lies closely by at 3.6 arcseconds away and shines at a magnitude of +7.8. The pair also known as STF 2404, HD 174569, SAO 104170, HR 7099.

Epsilon Equulei (Struve 2737): A Quaint Star System of Yellow and Violet in Equuleus

The delicate and pretty magnitude 5 triple star Epsilon Equulei shines down from the constellation Equuleus on late summer and autumn nights. Learn more about this pretty star and see what it looks like through a backyard telescope.

Struve 2690 (15 Delphini): A Quaint Multiple Star System in the Dolphin’s Tail

15 Delphini, also known as Struve 2690, is a multiple-star system that is visible during late summer and autumn nights. Most observers will see a quaint pair of equally bright stars in the tail of the constellation Delphinus, but more star lurk nearby!