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Open Clusters in Cassiopeia

OBSERVING REPORT

OPEN CLUSTERS IN CASSIOPEIA

Date: September 15, 2012
Time: -
Binocular: 9x60
Observer: Leo Cavagnaro





























I started an observing project late that night so in the meantime I decided to observe some open clusters that lie in the beautiful constellation Cassiopeia, waiting for the moment of the beginning of my major observation.


Messier 52. Trumpler classification I,2,r. This 5 kly distant cluster, situated roughly 43 arc minutes south of the 5 magnitude star 4 Cassiopeiae, is visible through this kind of binocular. A few stars seem to be discerned when you see it from a dark sky site. It was discovered in 1774 by Charles Messier.   




NGC 7789. Trumpler classification II,1,r. Through this kind of small optical device, this open cluster looks like a round nebulous patch, appearing rather faint. However, it is an object for binoculars.
It was a discovery of Karoline Lucretia Herschel in 1783. It can be found aproximately 51 arc minutes south-southeast of the 4.5 magnitude star ρ Cassiopeiae.



NGC 129. Trumpler classification IV,2,p. Small stellar swarm close to the 6 magnitude star HD 2626, a double star according to the SIMBAD Database. Some of the brightest members can be glimpsed using averted vision. Friedrich Wilhelm Herschel discovered this object in 1788. NGC 129 lies at the middle of the imaginary line that connects the bright stars β (Caph) and γ Cassiopeiae.



NGC 225. Trumpler classification III,1,p,n. It looks like a faint hazy patch in the central part of constellation Cassiopeia, between the stars κ and γ Cassiopeiae. Known as the Sailboat Cluster, it is a loose and poor cluster. It was discovered in 1784 by Karoline Lucretia Herschel (sister of William) using a 4-inch reflector telescope.




NGC 457. Trumpler classification I,3,r. This cluster, discovered by Friedrich Wilhelm Herschel in 1787, usually known as the "ET" or Owl Cluster, is easy to find because you just need to aim your instrument to the naked eye star φ Cassiopeiae (visual magnitude 5). The cluster, that looks like an elongated nebulosity through a binocular, is detected immediately to the northwest of that star. In some sense, this cluster reminds me a short tail of a comet. Some stars can be glimpsed when using averted vision.


Stock 2. Trumpler classification III,1,m. Situated about 5° south-southeast of the 3.4 magnitude star ε Cassiopeiae (Segin), it is an interesting open cluster, big, and elongated in the same orientation that the double cluster of Perseus (W-E). It is a swarm of stars with similar brightness that is easily discerned through a binocular. Stock 2 lies within a triangle formed by three stars (visual magnitudes between 6.5 and 7) that are brighter than the cluster members.