Beginner's Guide to Astronomy
Choosing and Using Charts
By Shawn Grant
Star charts are the celestial road maps of the sky. In order to find objects you need a good star atlas. You may ask which star atlases are good to buy with so many on the market. There are a large variety of atlases on the market and those of you with a computer the choice can even be more confusing. There are different types of atlases. A basic atlas with stars to 6th magnitude and a thousand or so deep sky objects and a detailed atlas with 9th to even 11th magnitude stars and several thousand deep sky objects.
A basic star atlas is a must for all no matter what your observing interest and skill is. Even if you own a detailed atlas such as Uranometria you still need a basic atlas to give a wide view of the sky. One of my favorite basic atlases is the Cambridge Star Atlas 2000 by Wil Tirion. It shows stars to 6th magnitude and labels the Byers, Flamsteed and common names. It has a catalog of 800 brightest deep sky objects. The nice thing about this chart on the left page it has all the info on the double star, variable stars and deep sky objects. It has coordinates, magnitude, and well you get the picture lots of information. The right page has the chart. This is an easy to read with symbols and color designate the objects. Sky Atlas 2000 is another great star atlas. It is a little more detailed then the Cambridge. It has stars to 8th magnitude and 2500 deep sky objects. This atlas balances wide field with detail. If you're just a casual observer and not after the obscure and fainter (more interesting objects) then Sky Atlas 2000 is all you would need. It comes in several different versions. One is just loose unbound charts that have black stars on a white background or white stars on a black background. The other version is charts in a nice spiral binding and they are laminated with the same types of background choices. I recommend getting only the spiral bound charts. The loose ones are hard to sort, damages easily with dew and they are general just a pain in the rear. It is definitely worth the extra cost in getting the bound charts. As far as which background to get the answer is what ever floats your boat.
It is necessary to get a more detailed chart to complement your basic chart to find obscure objects. A more detailed atlas shows more stars to make star hopping a breeze. If you're going to explore the Virgo Cluster with just Cambridge or Sky Atlas all I can say is good luck. Uranometria has very detailed charts just showing a small area of the sky on each chart. It plots stars to 9th magnitude for easy star hoping and over 10,000 deep sky objects. It comes as a nicely bound 2 volume hardback book. Volume one is the northern sky down to –6 declination and volume two is the southern sky up to +6 declination. A new atlas was released recently called the Millennium Star Atlas. It is a pricey three-volume set. It plots stars to 11th magnitude and I can say with experience 11th magnitude stars makes a huge difference on the success of finding an object. It plots over 10,000 deep sky objects. The cost of this set is a whopping $250. Worth the cost it depends. If you are a hard core deep sky observer without a computer it probably is worth the money, If you have a computer then no.
Computers have revolutionized the charting world. Programs like Guide, Skytools and MegaStar charts stars to 15th magnitude and over a million deep sky objects (wow). They also have a large database of asteroids and comets. MegaStar prints nice clean charts at any field of view. Guide prints excellent charts too but not quite as nice as MegaStar. Skytools has a nice feature where it will print a 3 tier chart with 3 different field of view. You can print anything from a finder chart for Pluto and asteroids to finder charts for elusive planetary nebula. You can add telrad and eyepiece overlays also. If you own MegaStar or Guide you may not need any other charts. You can print your own charts put them in plastic coverings and place them in a notebook.
I hope this made things easier to help you choose the right chart for you. The bottom line is charts make observing easier and more fun.