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| Winter | Spring | Summer | Autumn |
| 1) AQUARIUS 2) PISCES 3) TRIANGULUM 4) 6) FORNAX |
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| Name | Magn. | Dist. (L.Y.) | Temp.°K | C. | Type | Greek | Const. |
| Sadalsuud | 2.91 | 710 | 6.000 | G0 | Beta | Aqr | |
| Sadalmelik | 2.96 | 680 | 5.800 | G2 | Alpha | Aqr | |
| Skat | 3.27 | 86 | 9.040 | A3 | Delta | Aqr | |
| Albali | 3.77 | 155 | 9.680 | A1 | Epsilon | Aqr | |
| Sadalachbia | 3.84 | 158 | 10.000 | A0 | Gamma | Aqr | |
| Ancha | 4.16 | 155 | 5.080 | G8 | Theta | Aqr | |
| Seat | 4.66 | 1.800 | 25.600 | B1 | Pi | Aqr | |
| Situla | 5.06 | 360 | 3.040 | M3 | Chi | Aqr |
 The Helix Nebula - NGC 7293 Planetary Nebula Magn. 6.5 . Dist. 330 l.y. The Helix Nebula is the closest and apparently largest of all planetary nebulae. Lying at a distance of perhaps 330 light years, it is the only planetary nebula for which a parallax could be obtained by ground-based observations. It is also one the apparently largest planetaries known: Its apparent size covers an area of 16 arc minutes diameter, more than half of that of the full moon; it halo extends even further to 28 arc minutes or almost the moon's apparent diameter. Although the nebula is quite bright, its light is spread over this large area so that it is not an easy object for visual observing; the Herschels have apparently never cataloged or observed it. The popular name Helix Nebula refers to the nebula's appearance on photographs. |  M 2 - NGC 7089 Globular Cluster Magn. 6.5 - Dist. 37.000 l.y. M2 has a diameter of about 150 light-years, contains about 150,000 stars, and is one of the richer and more compact globular clusters. This cluster is of notable ellipticity, as can be noted in photographs; it is extended in position angle 135 deg. At about 37,000 light years, it lies well beyond the Galactic Center. Visually it is of apparent magnitude 6.5 and about 7 minutes of arc in diameter, but photos reveal that it extends out to a diameter of 12.9 arc minutes. Its brightest stars are red and yellow giants of magnitude 13.1, while its horizontal branch stars have an apparent brightness of 16.1. The cluster's overall spectral type has been given with F0. |
 M 73 - NGC 6994 - Open Cluster ?Magn. 9.0 Charles Messier described it as: "Cluster of three or four small stars, which resembles a nebula at first glance, containing very little nebulosity; this cluster is located on the parallel (of declination) of the preceding (M 72); its position has been determined from the same star (Nu Aquarii)." What remains to clear up to now is the check if the 4 stars in M73, or at least some of them, are physically related. There was always a great fraction of astronomers who believed that M73 is an asterism, a chance alignment of 4 stars at different distances. Other, however, tend to join the opinion of P. Murdin, D. Allen, and D. Malin, expressed in their Catalog of the Universe: "[The authors] suspect in fact that M 73 might be a real little cluster, for the following reason. On average there are 60 stars per square degree which are brighter than magnitude 12, as are the four stars of M 73. The probability of finding four such stars by chance in a given area of sky one arc minute across (like M 73) is about two chances in a billion. However, there are 150 million such little areas on the sky, so the chances are only one in four that such random asterism exists on the sky. M 73 could be it, but we would gamble that it is a genuine multiple star of some kind." So there is still an obvious need for more and newer data. |
| M 72 - NGC 6981 Globular Cluster Magn. 9.4 Dist 56.000 l.y. | 
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| Name | Magn. | Dist. (L.Y.) | Temp.°K | C. | Type | Greek | Const. |
| Kullat Nunu | 3.62 | 217 | 5.220 | G7 | Eta | Psc | |
| Al Risha | 3.96 | 650 | 9.040 | A3 | Alpha | Psc | |
| Torcularis Sept. | 4.26 | 142 | 5.080 | G8 | Omicron | Psc | |
| Fum Al Samakah | 4.53 | 415 | 14.800 | B6 | Beta | Psc |
M 74 - NGC 628 - Spiral Galaxy
Magn. 9.7 - Dist. 31.6 mill. l.y.
This conspicuous spiral is a prototype of a grand-design Sc galaxy. Its distance may be about 30 million light years. Then its spiral arms are about 1000 light years broad. They are traced with clusters of blue young stars in color photos, and reach out to cover a region of more than 10 minutes of arc in diameter, corresponding to roughly 95,000 light years, or about the same size as our Milky Way galaxy. The nucleus is small and bright.
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The Triangulum galaxy M33 is another prominent member of the Local Group of galaxies. This galaxy is small compared to its big apparent neighbor, the Andromeda galaxy M31, and to our Milky Way galaxy, but by this more of average size for spiral galaxies in the universe. M33 was probably first found by Hodierna before 1654 and independently rediscovered by Messier in 1764.
The brightest and largest HII region (diffuse emission nebula containing ionized hydrogene) situated in the northeastern part of the galaxy has obtained a NGC number of its own: NGC 604, it is apparently the bright knot near the top of our image. This is one of the largest H II regions known at all: it has a diameter of nearly 1500 light years, and a spectrum similar to the Orion nebula M42.
 | NGC 604 |
M33 was among the first "spiral Nebulae" identified as such by William Parsons.
Its angular dimension of 73 arc minutes in major axis (about 2.5 times the Moon's diameter) corresponds to about 50,000 light years, half the diameter of the Milky Way. However, the faintest outlayers seem to reach more far out, so that the true diameter may be at least 60,000 light years. The pronounced arms exhibit numerous reddish HII regions (including NGC 604), as well as blueish clouds of young stars. A strong X-ray source is also situated in this galaxy.
For the observer, this galaxy can be glanced with the naked eye under exceptionally good conditions; for most people, it is the most distant object visible to the naked eye. It is outstanding in good binoculars, but as its considerable total brightness is distributed quite evenly over an area of nearly four times that covered by the full Moon, its surface brightness is extremely low. Therefore, it is difficult to impossible to view this galaxy in telescopes which do not allow low magnification - lowest is best for this object !
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| Name | Magn. | Dist. (L.Y.) | Temp.°K | C. | Type | Greek | Const. |
| Fomalhaut | 1.16 | 21.9 | 9.040 | A3 | Alpha | PsA |
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| Name | Magn. | Dist. (L.Y.) | Temp.°K | C. | Type | Greek | Const. |
| Fornacis | 3.87 | 43 | 6.240 | F8 | Alpha | For |
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| Please e-mail to Carlo Corti any suggestion and criticism |
