The best, as far as I can determine, is Starry Night (It is available for both the Mac and PC platform) It comes in many flavors, ranging from novice to professional, and the price increases as one advances... Its somewhat clunky interface, takes some time to get used to... other than that it's terrific and anyway you just may like the way it's set up.

 

 

Distant Suns

Way back when I was an Amiga user, the program of choice was Distant Suns. It's a nice program, now in it’s 16th year and is still available for PC and Mac (OS 9 only)

You can download a free light (SE) version) of Distant Sun’s for the PC at:

 

 

They also have a nifty screen saver called

Distant Suns-Grand Tour 3D Screensaver, the free version copyright 2004 by Mike Smithwick

Deep Sky

I use Deep Sky for observation maps and a detailed “what’s up” data base

 

Cartes Du Ciel

There is a free star map program called Cartes Du Ciel, but it doesn't keep track of our Moon or the planets, and is not the easiest program to use.

Deep Sky uses Cartes Du Ciel as an alternative visual sky data base

 

 

Celestia

A free space simulation that lets you explore our universe in three dimensions. Celestia runs on Windows, Linux, and Mac OS X.

 

The following url will take you to the course material  for the Cosmic Zoom class

As I update the class material the content will change...