Object list indexed by constellation Part Two, Cy - La.

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Cygnus

Binary stars:-

Beta1 and beta2 form an extraordinary binary: gold and blue (or perhaps yellow and blue-green). The component is quite wide, making it a popular object for binoculars. AB: 3.1, 5.1; PA 54 degrees, separation 34.3".

Delta Cygni is a visual binary with an orbit of 828 years. Presently the values are: 2.9, 6.3; 224º, 2.5".

Mu Cygni is another visual binary (4.8, 6.1) with a long orbit, 789 years. For the next fifty years the orbit will continue to appear to approach the primary (as seen from the earth). The 2000.0 values are: 309º, 1.85".

Tau Cygni is a visual binary with a 49.9 year orbit: 3.9, 6.8. The 2000.0 year values are PA 328º, separation 0.8".

30 Cygni and 31 Cygni [omicron1] form a wonderful triple, suitable for binoculars: AB: 4.0, 5.0; 333º and separation 338" (orange and turquoise). ? 7.0; 173º, separation 107" (blue).

61 Cygni is another fine binary of two orange stars: 5.2, 6.0. The 2000.0 values are PA 150º, and separation 30.3". 61 Cygni also holds the distinction of being the first star to have its parallax measured. This occurred in 1838, by Friedrich Wilhelm Bessel, a German astronomer

Struve 2486 (Cyg) RA: 19 12.1 Dec.: +49 51 Magnitudes: 6.6 6.8 Separation: 7.9 Position Angle: 210 This nice double has two comparably bright yellow stars, trying to touch each other. This duo lies completely E in the constellation, that is E of the left wing of the Swan.

Otto Struve 394 (Cyg) RA: 20 00.2 Dec.: +36 25 Magnitudes: 7.1 9.9 Separation: 11 Position Angle: 294 It is a nice little double in the rich milky way field along the line from Deneb to Albireo, just above the middle star Eta. It reveals an orange color for the primary and a purple color for the companion, highly fainter but fairly well separated.

Otto Struve 437 (Cyg) RA: 21 20.8 Dec.: +32 27 Magnitudes: 6.2 6.9 Separation: 2.1 Position Angle: 28 A yellow primary is almost touching an only slightly fainter component with an orange-like color. This beautiful pair is located E of the right wing of the Swan.

Nebula:-

NCC 7000 is called "North American Nebula" because of its shape. It's a bright slightly greenish emission nebula. The nebula is described in most references as "bright" but in fact you'll find it is extremely faint. It is best seen in binoculars, and is found between alpha Cygni and xi Cygni.

The Veil Nebula West (NGC 6960) and The Veil Nebula East (NGC 6992/95) are fine filaments seemingly suspended in the cosmos. It takes quite a large scope, perfect conditions, and plenty of patience to appreciate their delicate lines. The nebulae are 2.5 to 3 degrees south of epsilon Cygni. The star 52 Cygni is in the same field as the western segment, and is the best starting point to search for the elusive nebulae. 52 Cygni is three degrees due south of epsilon Cygni (and it's a binary as well, Struve 2726: 4,9; 67º, 6.6").

Cluster:-

M29 (NGC 6913) open cluster A cluster of about 50 stars near Gamma Cyg. Magnitude 6.6; diameter 7'; R.A. 20h 23.9m, Dec. +48° 26'.

M39 (NGC 7092) open cluster About 50 stars in a loose grouping about 9o east and slightly north of Deneb. Magnitude 4.6; diameter 32'; R.A. 21h 32.2m, Dec. +44° 20'.

Rocking Horse Cluster (NGC 6910?). I think I found it at 39x, but increased the power to 100x for a more optimal view. I noticed how more stars jumped out at higher power, changing the view of the cluster. What appeared to be the "rocker" asterism at low power, appeared to be the horse and rider's back at higher powers,
with fainter stars showing up to form the new rocker.

Galaxies:-

Cygnus A Cygnus A is the second brightest source in the 'radio sky', after the supernova remnant known as Cas A. This pecularly-shaped galaxy is considered to be a billion light years distant, and is an object of intense investigation. Two lobes of radio emission are fed by jets of energetic particles from the galaxy core. (I thank Philip Blanco for this description. Philip has a web page devoted to Cygnus A. Those interested just set their search engine to 'Cygnus A'.)
Cygnus A is found in a highly nebulous region of the constellation, about three and a half degrees west of gamma Cyg.


Delphinus

Binary stars:-

Beta Delphini is a very close visual binary with orbit of 26.7 years. Epoch 2000 values: 4.0, 4.9; PA 343º, separation 0.5".

Gamma1 and gamma2 Del form a fine binary with (perhaps) subtle colour change (observers argue over this; some find them both yellow, others that the companion is greenish or bluish): 4.5, 5.5; PA 268º, 9.6"

Struve 2725 is a wonderful sight in the same field as gamma Del (to the SW): 7.3, 8.0; PA 9º, separation 5.7".

Cluster:-

NGC 6934 The outer edge resolves at 80x, in the 16" f5 Newt at over 200x it resolves almost to the core.

NGC 7006 is a very remote globular cluster, perhaps as far as 200,000 light years away. Because of its distance it is extremely difficult to resolve. It is located fifteen arc minutes due east of gamma Delphini.

NGC 6950

Nebula:-

NGC 6891 a triple shell planatary, about 18' accross. 12400 ly away.

NGC 6905 called the blue flash nebula 4 degree east of Eta Sag.

Asterism:-

Theta Del Group this is a 1 degree asterism close to Theta Del.
Pokus 1 another asterism just above Gamma Del. Is 6.5' long and is described as the lute.



Draco

Binary stars:-

Mu Dra RA: 17 05.3 Dec.: +54 28 Magnitudes: 5.6 5.7 Separation: 1.9 Position Angle: 8 Two equally bright yellow stars are matched together. Mu Dra is the star just W of the dragon's head. More to the west also lies the nice wide double 16 and 17 Dra.

Nu Draconis is a splendid fixed binary, found in the dragon's head. Two similar 4.9 visual magnitude stars: PA 312º and separation 61.6".

Psi Draconis is also easily resolved: 4.9, 6.1; PA 15º, separation 30.3"

Omicron Draconis has a fine colour contrast, orange and blue. Magnitudes 4.7, 7.5; PA 326º, separation 34.2".

17 Draconis forms a magnificent fixed triple with 16 Draconis. 17AB: 5.5, 6.4, PA 108º, separation 3.4"; 16 Draconis is component ? PA 194, separation 90.3".

26 Draconis is a close binary with orbit of 76 years. The component is currently at PA 334º and separation 1.6". There is a faint (10m) very wide third member, at PA 162º and separation 12.3'.

41 and 40 Draconis (Struve 2308) form a pleasant, fairly wide, binary of two cream-coloured stars: 5.7, 6.0: PA 232º, 19.3". Note that 41 is the primary.

Struve 2398 is an extremely near binary at only 11.3 light years. It consists of two red dwarfs, 8.0, 8.5; PA 163º, separation 15.3". It is thought the companion has an orbit of roughly 350 years. The binary is found just between omicron Draconis (which to the east) and 39 Draconis.

Struve 1362 (Dra) RA: 09 37.9 Dec.: +73 05 Magnitudes: 7.2 7.2 Separation: 4.9 Position Angle: 129 Two equally bright stars are almost in contact. This pretty double lies at the very end of the Draco tail, NW of Ursa Major. The companion is slightly yellowish.
Struve 2155 (Dra) RA: 17 16.1 Dec.: +60 43 Magnitudes: 6.8 10.1 Separation: 9.8 Position Angle: 114 In the same area of this double stands a bright orange variable star VW Dra. The double is a classic yellow-blue pair, the component being much fainter and fairly wide split. It is located north of the dragon's head

Galaxies

M102 (NGC 5866) is an edge-on galaxy with dust lane and brightly glowing centre. The galaxy is four degrees southwest of iota Draconis.

NGC 5907 is in the same region one degree east of M102. This is another edge-on (nearly flat) galaxy with dust lane.

NGC 5985 is an inclined spiral, quite faint unless under ideal conditions. NGC 5985 is midway between iota and theta Draconis; (NGC 5982 is in the same field to the west. This elliptical gallaxy is
considerably smaller but about the same magnitude, around 12).

Nebula:-

NGC 6543: a planetary nebula that appears as a miniscule blue-green disk. Because of its blue-green colouring, it is sometimes called the Cat's Eye Nebula. It's located halfway between delta and zeta Draconis. It's exact distance isn't known; estimates vary from 1500 to 3500 light years.


Eridanus

Binary stars:-

Theta1 and theta2 Eridani form an attractive pair: 3.4, 4.5; PA 88º, separation 8.2".

Omicron2 Eridani is an interesting triple system only 15.9 light years away. AB form a very wide pair, with orbit of perhaps 8000-9000 years: 4.5, 9.7; PA 105º, separation 82.8".BC form a close visual binary with orbit of 252 years. The primary is a white dwarf, with about twice the diameter of the earth. The component a red dwarf. In fact omicronB is considered the easiest white dwarf for amateur telescopes. The component C has an extremely small mass, considered to be about 0.2 solar mass. 9.7, 10.8; presently PA 337º and 9.3" separation.

32 Eridani is another attractive pair, with colour contrast - yellow and blue: 5.0, 6.3; 347º, 6.9" separation. 32 Eri is near the northern boundary, 10º west of nu Eri (or about 10º north of gamma Eri).

p Eridani is a visual binary near the southern boundary of the constellation. It has an orbit of 483.7 years: 5.8, 5.8; currently the component is at PA 191º and separation 11.5". The binary is found one degree north of Achernar (alpha Eri).

Galaxies:-

NGC 1232 is a spiral galaxy seen face on. It's 2º NW of tau4 Eri.

NGC 1300 is a splendid barred spiral. It's 2.3º due north of tau4 Eri.



Equuleus

Binary stars:-

Gamma Equulei (also known as 5 Equ) is a multiple system with quite faint components (although C is only optical). AB: 4.7, 11; PA 268º, separation 1.9". ? 12; PA 5º, 47.7". ? 6; PA 153º, 352".

Delta Equulei (also known as Struve 2777) is a multiple system including one of the most rapid visual binaries, with an orbit of only 5.7 years: 5.2, 5.3; 2000 values: PA 33º, 0.2". AC: 9.4, PA 14º, 47.7".

Epsilon Equulei (Struve 2737) is also a multiple system: AB: 5.2, 6.0; PA 288º, 0.9" ? 7; PA 70º, 10.6". ? 12.5; PA 280º, 74.8".

Lambda Equulei (Struve 2742) is perhaps the most attractive binary in Equuleus. It has two equal but rather faint stars: 7.4, 7.4; PA 218º, separation 2.8".

Struve 2786 (Equ) RA: 21 19.7 Dec.: +09 32 Magnitudes: 7.2 8.3 Separation: 2.5 Position Angle: 185 A primary with a yellow tint and a secondary with a blue tint, are almost touching each other. The companion is a moderately fainter one. The nice pair Struve 2793 lies directly E of it. The little constellation SE of the Dolphin, shows two other doubles, Epsilon and Gamma.


No deep space objects



Gemini

Binary stars:-

Alpha Geminorum is a well-known binary with the companion currently (2000.0) at a PA of 65º and separation 3.9". The visual magnitudes are 1.9 and 3.0. the entire system is comprised of six stars, including a red dwarf, Castor C, which slowly revolves around both Castor A and Castor B. This star is also a variable (and therefore catalogued as YY Gem).

Delta Geminorum: visual magnitudes 3.5, 8.2, PA 225º, separation 5.8". The period is estimated at 1200 years; the companion is an orange dwarf which may be difficult to resolve in smaller telescopes.

Eta Geminorum is a visual binary that takes some work to resolve; the companion is only 8.8 (primary is 3.3), the PA is 266º and separation 1.4". This is nearly a fixed binary, with very little movement.

Kappa Gem RA: 07 44.4 Dec.: +24 24 Magnitudes: 3.6 8.1 Separation: 7.1 Position Angle: 240 This needs a same effort like that other tight double Delta Gem. A tiny blue gem is touching the bright orange main star. Kappa is found just south of Pollux.

38 Gem RA: 06 54.6 Dec.: +13 11 Magnitudes: 4.7 7.7 Separation: 7.1 Position Angle: 240 An easily resolved gap between the little light purple attendant and the bright deep yellow primary. The double lies SE of Gamma Gem, the SW corner of Gemini.

Struve 1108 (Gem)RA: 07 32.8 Dec.: +22 53 Magnitudes: 6.6 8.3 Separation: 11.5 Position Angle: 178 An orangish primary has a little but obvious purple point next to it, fairly well split. The pair is spotted E of Delta Gem, the area where you also find the Eskimo Nebula and another fine double Struve 1083.

Struve 1083 (Gem) RA: 07 25.6 Dec.: +20 30 Magnitudes: 7.2 8.3 Separation: 6.4 Position Angle: 44 This pair has two contrasting colors, a deep yellow primary and a moderately fainter dark bluish green companion, considerably close. The double is located directly W of the Eskimo Nebula, also another fine double Struve 1108 lies at its north.

Clusters:-

M35 (NGC 2168). This is an open cluster easily enjoyed in small scopes. It lies just 2.5 degrees northwest of eta Geminorum. This cluster is extremely attractive, with gently curving rows of glittering stars. Several hundred stars make up the group, which is perhaps 2500 light years away.

Nebula:-

The Eskimo Nebula (NGC 2392) is one of the more distant nebulae at an estimated distance of 10,000 light years. There is a tenth-magnitude central star. If you do have a large enough scope, be prepared for anything: Burnham thought the Eskimo Nebulasuggested "the classic and unforgettable features of W. C. Fields." While you can locate this blue-green object in small scopes, it takes a very large telescope to see the "face" of this nebula, the eyes, nose, and mouth and the "fur collar" that gave it its name. To find this rather small planetary nebula draw an imaginary line between kappa Geminorum and lambda Geminorum. Now draw a perpendicular line from delta Geminorum, and just about where this line meets the other one is where you'll find the Eskimo Nebula.

Hercules

Binary stars:-

Alpha Herculis is a visual binary with a very long period, something like 3600 years. 3.2, 5.4; PA 104, separation 4.6".

Zeta Herculis is a rapid binary with colour contrast, a yellow primary and red companion with a period of 34.45 years: 2.9, 5.5. The 2000 values: PA 12º degrees, and the separation 0.7".

Delta Herculis RA: 17 15.0 Dec.: +24 50 Magnitudes: 3.1 8.2 Separation: 8.9 Position Angle: 236 Close to the bright white primary twinkles a blue tiny star. Delta Her is the most SE star of the hourglass pattern of the Strongman

Kappa Herculis is an easily resolved binary: 5.3, 6.5; PA 12 degrees, separation 28.4".

Mu Herculis BC (1.09â€; 10.2, 10.7)

Rho Herculis: two white stars which make a lovely double. 4.6, 5.6; PA 326, separation 4.1".

56 Her RA: 16 55.0 Dec.: +25 44 Magnitudes: 6.1 10.6 Separation: 18.1 Position Angle: 93 Next to the nicely orange primary stands a very small bluish point easily far from it. This fine duo lies in the middle of the bottom zone of the hourglass pattern of the constellation.

95 Herculis is a very attractive double with contrasting colours, often described as gold and silver (although you may disagree): 5.0, 5.1; PA 258 degrees, separation 6.3".

99 Herculis is a very close rapid binary: 5.1, 8.4; currently the PA is 92 degrees and the separation 0.3".

100 Herculis is another gorgeous binary of two equal white stars easily resolved. 5.9; 5.9; PA 183 degrees, separation 14.2"

Struve 2120 (Her) RA: 17 04.8 Dec.: +28 05 Magnitudes: 7.3 10.1 Separation: 16.3 Position Angle: 234 It lies NW of the most SE star of the hourglass pattern of Hercules. It is a nearly orange star with a much fainter bluish star fairly next to it.

Struve 2319. This is a very beautiful binary of two rather faint stars: 7.2, 7.6; PA 191 degrees, separation 5.4".

Struve 2063 (Her) RA: 16 31.8 Dec.: +45 36 Magnitudes: 5.7 8.2 Separation: 16.4 Position Angle: 195 It lies north of the most NW star of the hourglass pattern of Hercules. It has a yellowish primary, and moderately wide from it a dark yellow much fainter attendant.

Struve 2411 (Her) RA: 18 52.3 Dec.: +14 32 Magnitudes: 6.6 9.4 Separation: 13.5 Position Angle: 95 This pair has an orange primary and moderately close to it a little gray companion. The pair is located in the most SE corner of the constellation, that is rather close to the most NW naked eye star of Aquila.

STF 2094 Mags 6.8 11.0 25.4" This is the AC pair.

STF 2087 Mags 8.84 8.90 4.9" C 11.5 119"

STF 2089 Mags 8.66 9.96 2.8"

STF 2110 Mags 6.10 10.80 18.0"

STF 2109 Mags 7.52 10.30 5.7"

STF 2102 Mags 8.43 11.29 13.7" Nice triple. 3rd* est 11.0 25"

STF 3127 Mags 3.14 8.30 11.0" Delta Her, large mag diff

STF 2145 Mags 8.87 10.55 18.3"

STF 2135 Mags 7.59 8.88 8.4" Nice close pair

Clusters:-

M13 (NGC 6205) is a spectacular globular cluster sometimes known as "The Hercules Cluster". It is universally acclaimed as the best globular in the northern hemisphere. This is a very compact cluster of over a million stars. It is also very old - at an estimated age of ten billion years. It's around 25,000-30,000 light years away. M13 lies on a line between eta Herculis and zeta Herculis, due west of pi Herculis.

M92 (NGC 6341) is also a globular cluster, located nine degrees northeast of M13, and six degrees directly north of pi Herculis.

NGC 6229

Abell 2199

Abell 2151

Planetary Nebula:-

NGC 6210 A bright inner ring surrounded by a faint outer ring. Magnitude 9.7; diameter 13" × 20" (inner), 20" × 43" (outer); R.A. 16h 44.5m, Dec. +23° 49'


Hydra

Binary stars:-

Alpha Hydra, Alphard (09h25m.1 -08°26') is a 1.9 magnitude class K3 star about 95 light years distant. The star is an optical double, with a 10th magnitude bluish companion.

Beta Hydrae is a pair of nearly equal stars (4.5, 5) at PA 8º and a separation of 0.9".

Epsilon Hydrae is a multiple binary; four stars can be seen and another has been calculated to exist. Components A and B form a rapid binary with a period of 15.05 years; its orbit is nearly circular. Presently (late February 1996) the companion star has a PA of 166º and separation 0.26". Component C is much easier to resolve, with a period of 990 years. At present it can be found at a PA of 298.5º and separation 2.7".

Chi1 Hydrae is a binary of two similar stars (5.8, 5.8) with an even more rapid orbit. Its period of 7.4 years means an exceedingly difficult binary to resolve. If you've a large enough telescope, you'll find the companion at these values in late February 1996: PA 31º and separation 0.046".

Sigma 1474 is a fixed binary forming a wonderful triple. AB: 6.8, 7.9; 24º and separation 70"; ? 6.9, 23º, 76" separation. To find the binary, locate nu Hydrae then move one degreee northwest. (Just north half a degree is the nearly attractive Sigma 1473.)

Struve 1270 (S1270) consists of a pair of stars, magnitudes 6.4 and 7.4.

54 Hya is an easy double star for small telescopes, consisting of yellow and purple stars of magnitudes 5.2 and 7.1, 150 light years away. 54 Hya is in the tail of Hydra, near gamma and R.

Clusters:-

M48 (NGC 2548). Messier actually gave the wrong location for this star cluster, putting it four degrees north of the current position. But by his description this seems to be the right object. Not terribly spectacular, this is a group of fifty stars, the brightest of which is about 8.8 visual magnitude. The cluster is thought to be about 1700 light years away, and is easily seen in binoculars or small telescope.

M68 (NGC 4590) is a much richer globular cluster of over a hundred thousand stars, resolved in medium-sized telescopes. The cluster lies in a desolate part of the sky. Locate gamma Hydrae then move west to beta Corvi. Now drop down three degrees to the brightest star in this region, a fifth-magnitude star (this is the binary B230: 5.5, 12; 170 degrees, separation 1.3"). M68 is about a half degree to the northeast.

NGC 5694 is an extremely compact globular star cluster, thought to be in the region of 100,000 light years away. The cluster sits just east of the mid-way point between pi Hydrae and sigma Librae, at the border with Hydra. From pi Hydrae move east until you encounter a group of five magnitude stars lined up roughly north-south. These are 54, 55, 56, and 57 Hydrae. NGC 5694 lies one degree west of 57 Hydrae.

Galaxies:-

M83 (NGC 5236) is a spiral galaxy sitting on the Hydra-Centaurus border farther to the east, nearly twenty degrees south of Spica (alpha Virginis). While Burnham says this is considered one of the brightest galaxies with a visual magnitude of about 8, other references give it only a 10. And since it is very diffuse, it may be difficult for those living in northern latitudes.

NGC 3109 is a small irregular galaxy between 4.5 and 4.9 million lightyears away in the direction of the constellation of Hydra. It is the most prominent member of a Local Group subgroup. Other names for this galaxy include h 3221 and GC 2003

Nebula:-

NGC 3242 clearly deserves to be a Messier object. Small but bright, at a visual magnitude of 8.6, this planetary nebula is often called The Ghost of Jupiter because of its slight resemblance (?) to that planet. Also at times called The Eye Nebula, perhaps a closer description. The nebula gives off a soft bluish colour, sometimes described as a "glow", that is clearly visible even in small scopes. The central star may be difficult to resolve: this is an 11.4m star, a blue dwarf considered to be as hot as 60,000 kelvin. The nebula is one of the easiest to find. Just locate mu Hydrae then move south two degrees. Trying to resolve the inner ring could prove difficult. Large telescopes should show the object as resembling an eye, with the central star the pupil. The greenish-blue colour adds to this intriguing sight.

NGC2610 a Planetary nebula in hydra at mag 13.0 size 50.0" x 47.0" Position: RA 08:33.5 DEC -16:09.5. It is pretty faint, pretty small and comet shaped with a star of about 12th magnitude at the tip. Averted vision makes it larger in size. Both the UHC and OIII filters are little help, both increase the contrast of the nebula, but make the star much more difficult to see. In my opinion, the view is better without a filter.

Lacerta

Binary stars:-

8 Lacertae is a multiple system with quite wide components; these are the three brightest components: AB: 5.7, 6.5; PA 186 degrees, separation 22.4". AD: 9.3; PA 144 degrees, 81.8". AE: 7.8; PA 239 degrees, 336.6".

Struve 2902 is the most attractive binary in Lacerta: 7.6, 8.5; PA 89 degrees, separation 6.4". The binary is 1.5 degrees SE of 2 Lacerta, along a line between 2 Lac and 6 Lac.

h1823 is a fine multiple system 1.5º northeast of 12 Lac. AB: 6.8, 12.5; PA 259 degrees, separation 19.2" AC: 8.5; PA 338 degrees, 82.1". AE: 8.9; PA 263 degrees, 18.3".

Struve 2894 (Lac) RA: 22 18.9 Dec.: +37 46 Magnitudes: 6.1 8.3 Separation: 15.6 Position Angle: 194 Next to the yellow main star stands a much fainter pink-like component, fairly wide split. This double is found just E of 1 Lac, the bottommost star of the Lizard.

Clusters:-

NGC 7209 is an open cluster of fifty stars ranging in visual magnitude from nine to twelve. The cluster is 2.5º west of 2 Lac.

NGC 7243 is another open cluster of forty or so stars; the brightest star here is a fine binary (Struve 2890: 8.5, 8.5; PA 11, 9.4"). The cluster is 2.5º WSW of alpha Lac.

Edited September 30, 2019 by tuckstar
Added another double star.