Who is still interested in paper star charts in this day of computerized planetarium/mapping programs? The traditional nonvirtual star atlas is dead as a doornail, right? Hardly! There are actually more print star atlases available now than there ever have been. Some amateurs do not own laptop computers, and not everybody who does wants to haul one out to a damp observing field. Sure, it is possible to print maps on a printer and take the hard copy onto the field, but many observers still like the convenience of a book of charts that covers the entire sky.
What is desirable in a set of star charts? Let us mention what not to get first. Avoid "mag 6" atlases. These charts only show stars as dim as magnitude 6 (lower magnitude numbers are brighter), which is the limit of naked-eye visibility. Forty years ago, books like the magnitude 6 Norton's Star Atlas were the principal tools of amateur astronomers, which is probably why we did not see many deep sky objects back then. The problem with them is not only that they do not show many of the thousands of deep sky objects visible in an 8-inch CAT, but they also do not show enough stars for star hopping to objects if a go-to scope is not being used (or if a go-to computer is acting cantankerous). There are plenty of good magnitude 8 atlases out there, and that is what is recommended both for go-to and non-go-to scope owners.
There are three books of charts—star atlases—in wide use by amateur astronomers today: Sky Atlas 2000 (Wil Tirion), Uranometria 2000 (Wil Tirion, Barry Rap-paport, and Will Remaklus), and The Millennium Star Atlas (Roger W. Sinnott and Michael Perryman). Sky Atlas 2000 is the baseline. It offers 81,312 stars and 2,000 deep sky objects. The 2,000 may not seem like many objects compared to the 100,000 or more contained in the average computer atlas, but it is guaranteed that it will take a long time to work through those 2,000 with a C8. Sky Atlas 2000 is available in several editions, but perhaps the best is the deluxe, which is comprised of twenty-six 21 x 16-inch, spiral-bound, white-sky charts printed in color. Sky Atlas 2000 is also available in a field edition, with white stars on a black sky, but this is much harder to decipher under a dim red light than dark stars on a white sky.
For years, Sky Atlas 2000 was the deepest of the deep. But then came the two-volume Uranometria 2000 to kick things up a notch. Uranometria includes an amazing 332,000 stars brighter than magnitude 9.5 and over 10,000 deep sky objects. To go this deep, Uranometria is composed of 259 charts that are 9 x 12-inches. Although this atlas is ideal for star hoppers, the small scale of these charts, 1.4° per inch, means a lot of page flipping is required to find objects of interest. Many Uranometria users keep a copy of Sky Atlas 2000 at hand to help them "navigate."
Do you want deeper still? The Millennium Star Atlas goes down to magnitude 11 (1 million stars) and contains 10,000 deep sky objects. This atlas is even fatter than Uranometria, with three volumes packed with 1,548 charts that are 9 x 13-inches. However, at this level, computer star atlases become more practical. A few clicks will center you on an object that would have taken a half hour of squinting and page flipping in Millennium.
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