Map VII Cassiopeia Cepheus Lacerta Perseus Andromeda Lynx Triangulum

Of the groups in this map, all are circumpolar apart from sections of Andrdomeda and Triangulum. Ursa Minor and Camelopardus are also shown but are described with Map III.

CASSIOPEIA, shown in Key Map I, is one of the most interesting and conspicuous of the northern constellations. The Milky Way passes through it, and there are many rich telescopic fields. Of the chief stars, Alpha (Shedir) and Gamma are variable; the others are Beta (2.3), Delta (2.7), and Epsilon (3.4), which of course serve as excellent comparison stars.

Double Stars.Alpha: magnitudes 2.2 (var.) and 9.0; distance 63"; P.A. 280°. A wide optical double.

Eta: magnitudes 3.7,7.3; distance 11".2; P.A. 298°. Binary.

Iota: a fine triple. Magnitudes 4.2,7.1,8.0; distances 2".3,7".5; P.A.s 251°, 113°°.

Variables. Gamma: magnitude 1.7 to 3.4: irregular, and now classed as a "pseudo-nova".A most peculiar star, with a most unusual spectrum.Between 1965 and 2005, its magnitude averaged around 2.3. It is well worth watching.

Alpha. This was long classed as a variable. Recently, doubts have been cast on the reality of the fluctuations, but my own rough observations between 1936 and the present time indicate that the magnitude fluctuates irregularly between 2.1 and 2.5. Also worth watching is the irregular Rho.

R: magnitude 5.3 to 13.0; period 432 days. Spectrum M.

Clusters and Nebulae. M.52: a fairly bright cluster. Alpha and Beta act as "guides" to it.

M.103; An open cluster close to Delta.

CEPHEUS. This is not too easy to identify. The chief stars are Alpha (2.4), Beta (3.1), Gamma (3.2),Zeta (3.3), and Eta (3.4). Gamma lies between Beta Cassiopeiae and Polaris; the main part of the constellation between Cassiopeia and Vega. The triangle made up of Zeta, Delta, and Epsilon is the most conspicuous feature. On the whole, Cepheus is rather a barren group.

Double Stars. Beta: magnitudes 3.3,8.0; distance 14"; P.A. 250°.

Kappa: magnitudes 4.0,8.0; distance 7".5; P.A. 122°.

Variables. Delta: Magnitude 3.5 to 4.4; period 5.37 days. The prototype Cepheid.

Mu: magnitude 3.6 to 5.1; irregular. Sir William Herschel's "garnet star". It is of type M and is probably the reddest of the naked-eye stars; a splendid object in a low power.

T: magnitude 5.5 to 9.6; period 391 days. Spectrum M.

AR; magnitude 7.1 to 7.8; period 116 days. Semi-regular.

LACERTA is a small constellation near Cepheus. It contains no star brighter than the fourth magnitude, and no objects of special interest.

PERSEUS. A grand constellation. It lies between Cassiopeia and Aldebaran; the chief star, Alpha (1.8) can be found by a line drawn from Gamma Cassiopeiae through Delta Cassiopeiae and extended. The other leading stars are Beta (Algol) (variable; 2.1 at maximum), Zeta (2.8), Epsilon and Gamma (2.9), Delta (3.0), and Rho (variable; 3.2 at maximum). The Milky Way is particularly rich in Perseus.

Double Stars. Zeta: magnitudes 2.8, 9.4; distance 12".5; P.A. 208°. The chief component is a very luminous B1-type super-giant.

Eta: magnitudes 4.0, 8.5; distance 28".4: P.A. 300°. The primary is yellow, the companion bluish.

Epsilon: magnitudes 2.9, 8.3; distance 9"; P.A. 009°.

Variable Stars. Beta (Algol); magnitude 2.1 to 3.3. The prototype eclipsing binary, fully described in the text.

Rho: magnitude 3.2 to 4.2; an M4-type irregular. A suitable comparison star is Kappa, magnitude 4.00.

Clusters M.34; a fine open cluster, roughly between Kappa Persei and Gamma Andromedae, visible to the naked eye on a transparent night.

H.VI.33 and 34. The "Sword-Handle" clusters, described in the text. They are visible to the naked eye, and in my view are the most beautiful of all open clusters. Between them is a faint red star.

ANDROMEDA. This is a bright constellation, the leading stars being Beta (2.0), Alpha and Gamma (2.1), and Delta (3.2). Alpha is included in the Square of Pegasus and is also known as Delta Pegasi. It can be found by means of a line drawn from Epsilon Cassiopeiae through Delta Cassiopeiae and extended.

Double Stars. Gamma: magnitudes 2.5, 5.0; distance 9".8; P.A. 060°. A grand double, the components being yellow and blue. The small star is again double; magnitudes 5.4,6.2; distance 0".7; P.A. 109°.

Variable. R: magnitude 5.9 to 15; period 410 days. A long-period M-type variable, too faint at minimum for small apertures. It lies near Theta Andromedae (4.4).

Galaxy. M.31; the Great Spiral, described in the text. It is visible to the naked eye as a misty patch close to Nu Andromedae (4.4), but a telescope of large size is needed to show its structure.

TRIANGULUM. A fairly conspicuous little group near Andromeda, the leading stars being Beta (3.0) and Alpha (3.4).

Variable. R: magnitude 5.8 to 12; period 266 days. Spectrum M.

Galaxy. M.33. A large but rather faint and ill-defined object, roughly between Alpha Trianguli and Beta Andromedae.

LYNX. One of the most barren of all constellations. It adjoins Camelopardus, and lies between Ursa Major and the Twins (Castor and Pollux). There are no bright stars or interesting telescopic objects worthy of mention here.


Map VIII. Cygnus, Lyra, Sagitta, Vulpecula, Delphinus, Equuleus, Capricornus, Aquila, Sagittarius, Scutum, Serpens, Aquarius

This is a very rich area, best seen in summer. Vega and Deneb are just circumpolar in England, and the approximate time of rising and setting for Altair are given below. It must be remembered that in all these "rising and setting" tables, allowance must be made for Summer Time.

January 1st Rises 6 a.m., highest in daylight, sets 8 p.m.

April 1st Rises midnight, highest 7 a.m., sets in daylight.

July 1st Rises daylight, highest 1 a.m., sets in daylight.

October 1st Rises in daylight, highest 7 p.m., sets 2 a.m.

Vega and Deneb are shown on the first key map. Vega is almost overhead at midnight near midsummer and can be recognized by its brilliance and by its bluish colour, which differs strongly from the yellowish hue of Capella, which occupies the overhead position at times during the winter.

LYRA. Though Lyra is a small constellation, and Vega is the only star above the third magnitude, it is remarkably rich in telescopic and other interesting objects. After Vega, the leading stars are Gamma (3.2) and the eclipsing Beta. The quadrilateral made up of Beta, Gamma, Delta, and Zeta is easily recognized.

Double Stars. Epsilon: the famous double-double, described in the text. The two main components can be split with the naked eye; magnitudes 4.5 and 4.7; distance 208". Epsilon1; magnitudes 4.6, 6.3; distance 2".8; P.A. 001°. Epsilon2: magnitudes 4.9,5.2; distance 2".2; P.A. 099°. Of the two, Epsilon1 is the easier to divide,but both pairs are well visible in a 3-inch O.G.

Zeta: magnitudes 4.3,5.9; distance 44"; P.A. 150°. A wide, easy double.

Eta: magnitudes 4.5, 8.0; distance 28"; P.A. 083°.

Vega: has a companion, magnitude 10.5, at a distance of 56" and a P.A. of 169°. This is an optical pair, not a binary system. The faintness of the companion makes it a convenient test object.

Variables. Beta: magnitude 3.4 to 4.4, period 12.9 days. Eclipsing binary, described in the text. Gamma is a good comparison star; others are Zeta (4.1) and Kappa (4.3). It may be added here that the magnitude of 4.1 for Zeta as seen with the naked eye is the result of the combined light of the 4.3 and 5.9 magnitude components.

R: magnitude 4.0 to 5.0; a red M-type semi-regular variable.

Nebulae. M.57. Planetary. The Ring Nebula, described in the text. It can be seen with a small aperture, but the central star is extremely difficult even with large instruments. The object is easy to find, as it lies directly between Beta and Gamma Lyrae.

CYGNUS. The Swan, but also, and perhaps more appropriately, known as the Northern Cross. It is a superb constellation, in a rich part of the Milky Way. The chief star is Deneb; other bright stars are Gamma (2.2), Epsilon (2.5), Delta (2.9), Beta (3.1), and Zeta (3.2). It is worth remembering that Beta, the faintest of the stars forming the Cross, lies roughly between Vega and Altair.

Double Stars. Beta (Albireo): magnitudes 3.1,5.1; distance 34".6; P.A. 055°.Yellow primary, blue companion. I regard this as the loveliest double in the sky, and it is a superb object in any small telescope.

Delta: magnitudes 3.0, 6.5; distance 2"; P.A. 240°. A well-known test. Binary, with a period of 321 years.

61: magnitudes 5.6,6.3; distance 28"; P.A. 142°. The celebrated star that was the first to have its distance measured.

Zeta: magnitudes 3.3, 7.9; distance 2".3. Binary; period 500 years.

Variables. Chi: magnitude 4 to 14; period 409 days. A good comparison star when Chi is near maximum is its companion Eta (4.03).

W: magnitude 5.0 to 7.0; irregular. An M-type variable. It lies close to Rho (4.2).

X: magnitude 6.0 to 7.0; period 16.4 days. A Cepheid,lying close to Lambda (4.5).

The famous variables U, R, and SS Cygni are described in Appendix 26.

Nebulae and Clusters. There are many nebular objects in Cygnus. One of the most striking is M.39, near Rho, a good open cluster and a fine sight in a small telescope.

VULPECULA is a small constellation near Cygnus. It contains no star brighter than magnitude 42. The most interesting object is M.27, the Dumbbell Nebula, a planetary; it is dim, but is well worth looking at, even though a telescope of some size is needed to show it properly. It lies not far from Gamma Sagittae. Vulpecula, the Fox, was once known as Vulpecula et Anser, the Fox and Goose; but nowadays the goose seems to have been discarded - possibly the fox has eaten it!

DELPHINUS. A beautifully compact little group, very easy to recognize. The brightest star is Beta (3.7). The most interesting object is the double star Gamma; magnitudes 4.5,5.5; distance 10".5; P.A. 270°. The primary is yellow, the companion green. The variables U and EU are described on page 267.

SAGITTA. Another compact group; the brightest stars are Gamma (3.7) and Delta (3.8). It lies between Altair and Beta Cygni.

EQUULEUS. The chief star of this little constellation is Alpha (4.1). Delta is an excessively close double, and a rapid binary.

PEGASUS. Most of this constellation, including the Square, is shown on Map X. The chief star in the present map is Epsilon (2.3), which is suspected of variability. Close to it lies the bright globular cluster M.15, a fine sight in a moderate telescope.

AQUARIUS also lies mainly in Map X. On the present map are Beta (2.9), Alpha (3.0), and two nebulus objects; the fine globular M.2, which I find fully resolvable with my 121-inch. reflector and which lies between Beta Aquarii and Epsilon Pegasi, and the beautiful planetary NGC 7293 which lies in the same low-power field as the orange star Nu Aquarii (4.5). Aquarius is a Zodiacal constellation.

AQUILA. the chief stars,Altair, is one of the first magnitude and is easy to recognize because it has a brightish star to either side, Beta and Gamma. As well as Altair, the constellation includes Gamma (2.7), Zeta (3.0), Theta (3.1), Delta and Lambda (3.4) and Beta (3.9). The line below Altair, made up of Theta, Eta, and Delta, is very easy to identify.

Variables. Eta: magnitude 3.7 to 4.5, period 7.2 days. A typical Cepheid.

R: magnitudes 5.7 to 12; period 300 days. Spectrum M.

SERPENS. This constellation is divided into parts, Cauda (the body) and Caput (the head), separated by Ophiuchus. Caput is shown in Map IX. The brightest star in Cauda is Eta (3.2); the most interesting object is the fine double Theta, magnitudes 4.5 and 4.5, distance 22", P.A. 103°. This is a splendid object, and is easy to recognize, as it lies in a rather isolated position nor far from Delta Aquilae.

SCUTUM. Though containing no star brighter than the fourth magnitude, Scutum lies in a rich part of the Milky Way, and shows some fine fields. There are several clusters. One of these is the "Wild Duck", M.11, one of the most beautiful open clusters in the sky and shaped like a fan; it lies near Lambda Aquilae. M.26, close to Delta Scuti (4.7), is another good open cluster. It is well worth while to sweep this whole region with low power. R Scuti is an interesting variable.

SAGITTARIUS. This is a large and bright constellation, but is always very low in England and cannot be seen to advantage; part of it never rises at all. The chief stars are Epsilon (1.8). Sigma (2.1, Zeta (2.6), Delta (2.7), Lambda, Pi (2.9), Gamma (3.0), Eta (3.2), and Tau (3.3). Deneb, Altair, and Sagittarius lie almost in a straight line, with Altair in the middle; this is probably the easiest way to find Sagittarius. It can be quite conspicuous on summer evenings. Adjoining Sagittarius, but too far south to be seen in England, is the little constellation CORONA AUSTRALIS (the Southern Crown).

Clusters and Nebulae. M.17: the Omega or Horseshoe Nebula, near Gamma Scuti; a fine object in a moderate telescope.

M.8: the Lagoon Nebula, an easy object near Mu Sagittarii.

M.22: a bright globular between Sigma and Mu, not far from Lambda.

CAPRICORNUS. Like Sagittarius, Capricornus is in the Zodiac. It is a rather barren group; the chief stars are Delta and Beta (each 2.9).

Double Stars. Alpha: magnitudes 3.7, 4.3; distance 376". This is a naked-eye double, and is easy to find, as the line of stars made up of Gamma Aquilae, Altair, and Beta Aquilae points to it. The fainter component is again double; 3.7, distance 7"; P.A. 158°, and the smaller component of this pair is again double, though a very difficult object.

Beta: a very wide double. Magnitudes 3.1,6; distance 205", P.A. 290°. The fainter component is again double; distance 1".3, P.A. 103°, but the companion is rather faint (10.6) and is thus rather difficult in small apertures.

HERCULES. A small part of Hercules appears in Map VIII, but most of the constellation lies in Map IX. The site of the 1934 nova, DQ Herculis, is marked. This is now a difficult object, and has been found to be a spectroscopic binary. It is described in the text.


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