NGC 2506 is a cluster in Monoceros. Seen at low power it looks extremely well like a comet. At 36x the cluster is unresolved, faint nebulosity surrounds five faint stars that are closely packed together. Even at 120x the cluster remains unresolved, but the five stars are more easily seen.
NGC 1647 is a spectacular cluster in Taurus, composed of 40 scattered stars. Its diameter is 45 arcminutes.
Harvard 20 is an interesting cluster in Sagitta, it has two bright stars to the west. Except these two stars, five more are visible. The stars of the cluster are grouped in the form of an isosceles triangle. Using averted vision I observed granulation in the background.
NGC 6940 is a beautiful cluster, extremely dense and large. It is formed of faint stars and looks like a small chunk of the Milky Way.
Collinder 69 is easily visible with the naked eye, it is the asterism that forms Orion’s head. The cluster is composed of 15 stars, surrounded by other three brighter ones. It is easily discernible from the background stars.
M39 is a cluster in Cygnus, composed of bright stars scattered around the field. It is best seen at low power.
NGC 6416 is located in Sagittarius, west of M6. It is an obscure and uninteresting cluster.
Placed between Delta and Gamma Cancri, M44 is easily visible with the naked eye on a dark sky. The cluster consists of a great number of stars, but because of its large diameter it is best seen in a finder scope. Observing at 36x I noticed an interesting grouping in the shape of a triangle, composed of bright stars.
The other open star cluster in Cancer is M67, two degrees west of Alpha Cancri. M67 is not very bright, it has only one brighter star in the north. The cluster is well resolved at 36x, but to eliminate the faint traces of nebulosity I used 120x.
NGC 2264 is composed of 20 stars gathered around a brighter one. The Cone Nebula, invisible through my 114-mm telescope, surrounds it.
Melotte 111 comprises the largest part of the constellation Coma Berenices. It is best seen with the naked eye, it barley fits in my finder scope. 25 stars with magnitudes below eight are visible.
NGC 752 is an interesting cluster in Andromeda. It is visible with the naked eye, its diameter is about one degree. I observed a bright star near the center of the cluster. NGC 752 is composed of 60 stars, it looks like a small chunk of the Milky Way. In the same field with the cluster I have observed the double 56 And, well resolved at 36x.
NGC 6939 in Cygnus appears in the same visual field with the galaxy NGC 6946. The cluster is small, faint, and largely unresolved at 36x. I have seen only four stars surrounded by nebulosity. Using a magnification of 120x the cluster is almost completely resolved.
Collinder 463 is composed of 30 scattered starsa and its shape is elongated. It is very discernible because it is placed in an area deprived of bright stars.
In Auriga you will find three interesting clusters, disposed almost in a line, only M37 a little more to the north than the other two. M37 is the most spectacular cluster in the group, very dense and large, with a diameter of 24 arcminutes. In the center of the cluster I have found a bright red star. M38 is the least bright and dense. M36 is pretty small, it has a diameter of 12 arcminutes and is somewhat denser than M38.
Also in this constellation I have found a beautiful cluster, little known to amateur astronomers. NGC 2281 has its stars grouped in the shape of the letter “S”. Using 36x the cluster is completely resolved, without traces of nebulosity. If you watch the field very carefully, you should see nearly 20 faint stars.
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