I sure like “2-fers” in the eyepiece, and this is a nice one. NGC 2818 is a planetary nebula apparently within the open cluster NGC 2818... yes, they both have the same designation, although the cluster of often referred to as NGC 2818A. Up until the end of the last century it was thought that the nebula was actually within the cluster, but in 2001 a comprehensive radial velocity study of stars in the cluster (by Mermilliod et al.) demonstrated that they are just a superimposed pair of objects in a chance alignment.
… although none of the planetaries have yet to be proven to be members of their respective clusters. I’m going to be sure to make this list a new observing project for myself, it should be fun!
Getting back to NGC 2818, from my usual observing location in the desert 60 miles east of San Diego, CA., these objects culminate at only about 22° above our southern horizon, in early March, so my views have not been particularly impressive, but nevertheless they have been quite appealing. The cluster itself has quite a few stars but they are all fairly faint, and the planetary is perhaps slightly west of the cluster’s center, is oval-shaped, and there are hints of some structure in moments of good seeing. The Hubble picture will make you want to head to somewhere south of the equator to get what must be really amazing views…
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