Palomar Globular Clusters - The Delaware Valley Amateur ...

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AI Lamperti Globular clusters are some ofthe oldest deep-sky objects, having formed during a galaxy's final condensation. As a result, they are also quite a distance from the center of the galaxy and are often found in the galaxy's halo. Many globular clusters can be seen in the Milky Way and even the globular clusters in our nearby neighboring galaxies are wi thin the reach of amateur telescopes. The Palomar globular clusters were found on the plates ofthe Palomar Observatory Sky Survey taken with the 48-inch Schmidt telescope in 1950s. There are 15 clusters on the list. David Ratledge wrote a comprehensive history with images of each of the globular clusters.! Many observers have reported their findings, e.g. Barbara Wilson. 2 However, a search of The Deep-Sky Observer Index only found two articles on Palomar 2 by Maurice Gavin 3 and Steve Gottlieb 4 Recently, an observing buddy of the author,Joe McCormick from the Delaware Valley Amateur Astronomers, asked if I had ever seen any of the Palomar clusters. A quick review of an electronic database indicated all were seen, some twice, save for two. Those two were immediately added to the list for the next observing session. The following descriptions were made by the author with 13-inch, 18-inch and 20-inch f/5 Dobsonian reflectors from dark sky sites in Pennsylvania, w ith one made in Weston, Vermont. Palomar 1 20-inch f/5, 272x To find it, I needed the Millennium Star Atlas to star-hop. The cluster was seen with direct vision under a triangular asterism. There may have been some resolution as a couple of stars were discernible. Estimated Globular Class XI (actually XII). Palomar 2 20-inch f/5, 272x This was observed on the same night as Palomar 1. The Millennium Atlas helped. It makes an equilateral triangle with two stars, with Palomar 2 at the apex. It is a hazy patch and not quite resolvable. Ie f l 5 T a a 9 22
Palomar 3 (left) 18-inch f/5.17, 177x & 256x This was a very small, very faint globular cluster and not resolvable. Seven years later: 20-inch f/ 5,272x. I needed the Millennium Atlas to find it. It is small with no resolution, like a round galaxy. Palomar 4 (right) 20-inch f/5, 272x It is located on the border of Coma Berenices and Ursa Major. This was a hard one; very faint, like an out-of-focus star. Palomar 5 (left) 18-inch f/5.17, 256x Looks like a faint galaxy with no resolution. Seven years later: 20-inch f/ 5, 272x. This was difficult to see and needed averted vision (scale 3) . Also I needed jiggling of the telescope and a cover over my head. It was a very faint hazy even glow in the area indicated by the atlas. No resolution seen. Palomar 6 (right) 20-inch f/5, 272x This one needed an averted vision scale #2. It was a hazy, faint glow with no resolution seen. Palomar 7 (IC 1276) (left) 20-inch f/5, 313x I could only make out a handful of stars: 3 bright ones and a couple of dim ones. There are probably more that are fainter. Palomar 8 (right) 18-inch f/5.17, 286x It looks like a faint galaxy. Eleven years later: 20-inch f/5, 313x. I would have missed it except the image showed the star field. It is small, like a minuscule open cluster. 23
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Palomar Globular Clusters - The Delaware Valley Amateur ...

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