There is a lot of inexpensive and free astronomy software on the web. The free software is distributed as 'freeware' and much of the inexpensive software is distributed as 'shareware'. Shareware can be downloaded for free and tried out. Then if you like it, you send the author a check, generally much less than you would expect to pay for regular commercial software. There is, of course, plenty of commercial software you can pay for upfront, but that is another story. My personal choices are unlikely to be right for you.
Of particular interest for our class is planetarium software. Planetarium software presents a map of the sky for any date and location on earth. This is useful for identifying that 'bright star' you see if the west after sunset, or such. It can be a good aid for learning the constellations, as you can customize the view to the exact time and place of observation. I also find it useful to find out what the moon will be doing on some future date. For instance, will the moon interfere with observation of the Leonid meteor shower this November or the Perseids next August?
An excellent place to start searching is the software resource page of the Bill Arnet. There is enough shareware and freeware here to keep you busy for months.
I am a PC user (not Mac). My personal favorite used to be Sky Globe. It is an old DOS program which is very easy to learn and use, is very fast and powerful, and fits on a floppy disk, but occasionally has trouble running under Win XP. If you know how to run a dos program under windows, try it. Please note, the address shown for KlassM software in the program is the authors original address. A newer address is shown in the <Order.doc> file. (However, the author appears to have disappeared with no forwarding address, as this is a very old program.)
Sky_Globe Zip File (You need to unzip yourself.)
Sky_Globe Self Extracting File (You need to trust my .exe file. It extracts to C:\Sky_Glob)
My current favorite program, which is sort of a windows version of Sky Globe, is called Planetarium Gold available from Fog Ware Publishing at U Fill It Up.com. Just search for <Planetarium> in their search bar. Currently it appears to be available as shareware. Try for free and pay if you like/continue to use. The site does have a lengthy registration process, unfortunately. There is an old demo version of this program called Stellar Pro 1.53e where the e stands for the English version of the original Japanese program. The demo version prints star charts stamped with the word 'unregistered'. Also the program does not appear to be Y2K compliant. It wakes up with a weird future date.
A free, windows program listed is Home Planet.
For a photo-realistic view of the sky, try Stellarium. This program displays beautiful skies.
Some of these programs will not automatically place an Icon on your Desktop to run them. You have to go to the program location and double click on the exe file. A Shortcut can be dragged to the Desktop for convenience.
Finally, for those who prefer the low tech Universe, the Royal Canadian Astronomical Society has a nice, free, do it yourself planisphere which can be printed out on heavy paper. For those who want to purchase a more sturdy one, I recommend the Miller Planisphere, for less than $15. Here is one supplier.
A free, advanced, and sophisticated planetarium program is Cartes du Ciel. Commercial programs of comparable power cost $50 to $100. Recommended.
These same people have also developed a free lunar atlas which is perfect for identifying the features you can see through your telescope on any date. This program, too, is easily worth $50 to $100. Highly recommended.
Some useful places to search for shareware and freeware are below. Try searching on key words like astronomy or planetarium.
The software resource page of Sky & Telescope Magazine: (They link to ZD Net.)
Planetarium Page of Stargazing Net
IUPUI 2008
(last updated 3-3-08)
