So far in previous blog entries we have darted around the sky using brighter deep sky objects as our guides. We have star-hopped in all directions from oc 2232 (or any other object of your choosing) using Method 1, not searching for anything in particular except for "what's out there." This adds some randomness to an observing session, and can lead to little discoveries that can become your very own. Next, using Method 2 we planned to view a series of specific objects immediately surrounding a brighter one (again, oc 2232). There are too many observers who merely dart from one bright object to another, and I'm hoping that a few of them will learn to slow down a bit and explore beyond those irresistible bright target objects.
Method 3 is for serious stargazers only, and requires patience and careful preparation. My preferred method of observing is by constellation. The whole, entire thing. Single, variable, double and multiple stars. NGC and a few IC objects. Some non-NGC and non-IC objects. The complete constellation in all its glorious detail, or as much of it as my current scope can find. I always have one or two constellations chosen for each season, and I finally need a new spring project and one for summer. I have began the onerous task of preparing Leo for upcoming sessions. Since Leo has over 350 NGC objects in it (not counting IC and the other lists), I am not going to suggest that you begin with this one. However, in future blogs I'll let you know how my planning and observing of Leo are coming along. I've already spent about 8 hours preparing, but then there have been plenty of cloudy nights to work on it.
I suggest beginning with a few smaller constellations, and the summer sky has some nice options. Lacerta, Sagitta, and Vulpecula are good choices to try out Method 3 for the first time. However, since I will be preparing Lyra soon, I will choose it as my example. So, then, in easy steps:
1) Choose a constellation (Lyra).
2) Gather your information sources. I use Uranometria 2000, 2nd ed., revised (All Sky), and its complementary Deep Sky Field Guide. I use Burnham's Celestial Handbook (Vol. Two required for Lyra) and Observing Handbook and Catalogue of Deep-Sky Objects, by Luginbuhl and Skiff. I also use the internet, including the Washington Double Star Catalogue.
3) Decide which objects you wish to attempt. The owner of a 6" telescope will choose differently than the owner of a 10" scope. Burnham's lists 3 1/2 pages of double stars. Go through the list and mark in pencil which ones you would like to view. Several will be too faint or too close to be of much interest to any except the owners of very large telescopes. There is also a page of variables, including one of the most famous in the sky (Beta). I like to choose variables based on several criteria, including interest to amateurs and colour (T Lyra is mentioned as being "very red." That always catches my attention.) There are 4 NGC objects listed, including 2 Messier objects. Luginbuhl and Skiff list 6 NGC objects. Uranometria lists 28!
4) Once you have decided what to view, it's time to plot them on your atlas (Uranometria). I use a fine point mechanical pencil. All of the NGC (28) are listed on the Uranometria charts for Lyra. There will be other types of objects, too. If you are only planning to see some of them, underline (in pencil) which ones you are interested in observing, or lightly circle them. If you think writing in pencil in a star atlas is Satanic, either get over it or purchase two copies--one to keep pristine, for whatever reason, and one that will detail your on-going voyage through the heavens. The variables and major stars will already be labeled, too. All you have to do is add in the names of the dimmer double stars, in their correct positions. The positions listed in Burnham's are off a bit, but after a few stars are plotted you will figure out by how much and easily match the r.a. and dec. given with the actual star on the map (you should not have to draw any actual stars--they should already be there, just unlabelled). I also circle the name/number of any star that I will be observing. This is a fun way to begin knowing your way around Lyra. With the atlas marked in pencil with the objects you wish to view, you are now ready to prepare your observing list on paper.
5) It is now time to prepare your observing list, the one you will take outside with you. My Leo list will be long enough to make into a small book. The Lyra list should be 4 or 5 pages. Yours will depend to what depth you wish to explore the constellation, as well as the size of your mirror. You may set up your list anyway you choose, but I recommend leaving room on the left side of the page to jot down the full object's name and any information you have about it. Double stars will have magnitudes and separation distance, which is essential to know in the field. I usually don't write down position angles, as I prefer to find that out myself at the eyepiece. Variables will have their minimum and maximum brightness, and their period. NGC objects will have sizes, magnitudes, and, for clusters, perhaps how many stars there are in it. List the objects and their stats down the left side, saving the rest of the page for field notes. Indicate the required chart number from your atlas, and leave diagram space on the right side for clusters, galaxies, etc. I use a shot glass to draw blank circles on my field note sheets--bottom of the glass for smaller NGC objects, and the top end for larger ones. I tend to begin observing a section of the constellation at a bright star or object, and star hop from there until I have seen and reported on everything in the vicinity (like Method 2, previous blog entry). Then I go on to another location, seeing everything near it, and so on through the constellation. If you have marked your atlas properly, you will be writing up your to-do list in the exact order you wish to peruse the constellation, and it will include a nice mix of objects..
I currently have three constellations on the go. Soon there will be five. My main autumn one is Cetus; my winter ones are Lepus and Monoceros. I am preparing a new one for spring (Leo) and summer (Lyra). In this way, I always have hundreds of observing objects awaiting.
Whichever method you use (Method 1, 2, 3 or a combination of them, as I do), you will soon learn to appreciate the less bright and flashy objects. You will train your eye to see details you never thought were there. You will gradually become knowledgeable about vast areas of the sky. You will get to know your scope even better. And you will still have lots of fun on cloudy nights, preparing your lists and transferring your rough notes into your official observing logbook. If you have questions or comments, please feel free.
In the next blog, I will talk about my newest telescope, and some of my early successes and failures with it. Clear skies, and happy Vernal Equinox.
Mapman Mike
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