The graphic quality is heavenly. If you love astronomy, then you will love Celestia. Not only do you get a planetarium-quality view of our own night sky, but you can change the location from Earth to that of most any other star in our portion of the Milky Way galaxy. From there you can view that location's night sky. Celestia includes over 100,000 stars from the Hipparcos catalog.
Let me give you an example of what you can expect. Clicking on Navigation in the menu, then Star Browser, you are shown a list of star names. At the top of the list is "Rigel Kentaurus A" (one of many names for our closest, bright neighbor, Alpha Centauri A). If you select this and click "OK," you are instantly taken to a point of view not far from the primary star of this three-sun system.
With your mouse cursor, you can click and drag the view a short distance to the constellation of Orion. There you will see an intruder next to the shoulder star, Betelgeuse. Clicking on any star will reveal a list of names and catalog numbers in the upper left corner of the software window. These are all aliases of the star you clicked. Clicking on this intruder reveals that the short trip to Alpha Centauri has visually moved the bright star, Sirius to Orion's shoulder. Imagine that!
A short distance from the nearby, distorted face of Taurus, the bull, shines a fourth magnitude, reddish star which happens to be the system's dimmest member, Proxima Centauri (Alpha Centauri C), at 0.2 light years.
A short distance in the opposite direction takes you to the Earth constellation Cassiopeia alongside M31 (Andromeda galaxy). The very recognizable "W" shape of Cassiopeia has an additional star in its zigzag pattern. This first magnitude star is none other than our own home system. At this writing, the view also includes the scintillatingly bright companion, Alpha Centauri B (apparent magnitude –18.41).
The software has a number of add-ons which extend its capabilities. In fact, you can create your own add-ons and modify graphics as you desire. The possibilities are endless.
The manual reveals a long list of things you can do with Celestia. You can pilot a starship toward Earth, dive down into its atmosphere, skim just above the oceans or continents and underneath the clouds, then zoom out toward Jupiter to dance amongst the colorful and detailed Galilean moons. You can then turn your sights on any star and travel there at hyper-light speed.