COMPUTERS AND CLUBS
Computers have revolutionized the way amateurs find information, but nothing can replace the advice of fellow skywatchers.
Personal computers and astronomy seem made for each other. One of the most useful pieces of software is a planetarium program, which is like an electronic star atlas. Some versions can be used to print out customized star charts— perhaps showing a select region of the sky or a new comet's path, or printed in mirror-image fashion to match the view through some telescopes and finderscopes.
You can set planetarium programs for any date thousands ot years into the past or future. They are indispensable for figuring out details such as what the sky will look like at a certain time, when Venus will be closest to the Moon, or where a comet will appear.
At the very least, these programs plot all Messier and many NGC objects and stars down to magnitude 9. More advanced programs contain databases of thousands more deep-sky objects from newer catalogs, as well as providing the option of loading the Hubble Guide Star Catalog from CD-ROM. This database contains more than 19 million stars and non-stellar objects.