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2/20/2016

Review of Planetary Nebula and How to Observe Them


     When I first started observing, the very first object I was able to star hop to and hunt down were the galaxies Messier 81 and Messier 82.  I can remember using a 8 inch dob and finally figuring out that my star hop was not working because I need to invert my map to what I was seeing. Once I got that down, the orientation came into being and I successfully star hoped to the pair of galaxies.  My next star hop was to Messier 108. This took some time but I was able to secure it. From here I decided to hop over to Messier 97 and take a look at what a planetary nebula looked like. I found Messier 97, and I became hooked. Galaxies I loved, a planetary nebula I fell in love with.  This night began a long, observing love affair with Planetary Nebula.  I love galaxies, I enjoy nebula, I like open clusters but I really enjoy chasing down and observing Planetary Nebula.  I find these objects fascinating as they show what the future destiny is for our Sun as it grows into a Red Giant as the hydrogen in it runs out, then the luminosity increases as helium is burned up resulting in a helium flash where the outward envelope enlarges again. This leads to the separation of outer envelope which is separated from an estimated four thermal pulses. The mass of the Sun will be half of what it currently is, condensed into an object the size of the Earth.

These objects can vary from being very easy to observe, to small and complex and hard to identify the details and shapes in these wonderful objects.  There are a wide variety of these objects to observe and larger aperture can truly help on some, while smaller aperture can be very effective for others of these objects. There use to be a wonderful site called Seasonal Planetary Nebula that had Planetary Nebula or PN by season. Unfortunately that site is no longer available though I do have that list saved in four Excel sheets for which I am grateful.



So when I discovered that Martin Griffiths in 2012 had published a book called Planetary Nebulae and How to Observe them, I had to purchase the book.  The book arrived from Amazon and I have had the opportunity to go through the book.  The book begins by giving a quick history of PN's and their observational history and why we observe them as we do.  This is followed by a section on how to observe PN's and what equipment is best, including telescopes, filters, observing techniques etc.  Following this comes a quick chapter on photographing PN's that is quick and resourceful, though not too in depth. The various PN catalogs is next as the author goes through the various catalogs that have PN's in them.  Of all the chapters in these sections I enjoyed the quick history of PN's and then the catalog of PN's was very helpful.

The next section is PN's by constellation. This section provides some of the major PN's by each constellation, with specifics and a finderchart, both a general and a more detail one. This is probably the most useful section of the book as it provides the observer actual PN's to go after.  Some are easy, some are moderately hard and a few are more challenging.  My only criticism of the book are two. One, the section of equipment is needing some updating and more detail on how higher magnification can and should be used to get details out of objects and what eyepieces can be used to do this.  My other criticism is that I would want more information on more PN's and perhaps list which season each constellation is best to observe in. This would be more helpful for beginners to intermediate amateurs.

So if your looking for a general book on observing PN's with some basic and good targets to go after, I do recommend this book.  Cost is about $40 with shipping.