Celestia is a free and open source space simulator that allows you to explore space right from your computer. on Windows, Mac OS X, and even Linux. Celestia has many very cool features, including an eclipse finder.
Not only does the eclipse finder allow you to find solar and lunar eclipses on Earth, but you can seek eclipses on other planets as well. I found out something really cool when checking out eclipses on Jupiter – because Jupiter is very large and has many moons, solar eclipses are very common.
There are even days when multiple solar eclipses take place on the same day on Jupiter. I found an article about a triple lunar eclipse on Jupiter that Hubble captured back in 2004. I used the eclipse finder to find the day it happened (March 28, 2004) and was able to simulate it.
WIth Celestia you can view celestial events that have taken place in the past or will take place in the future. Events can be viewed as they would have occurred in real-time, or time can be sped up. You can also run slower than real-time, but I don’t find that feature all that useful since most celestial events take place over several hours or years.
There are numerous add-ons and textures available at the Celestia Motherlode. The add-ons provide additional celestial bodies and spacecraft not included by default. The textures provide more detail for planet surfaces, stars, and star systems as well.
If you are viewing the earth, you can enter specific coordinates you want to visit and use the surface view (CTRL-G in windows) to see the night sky as you would from your backyard.
This is a great way to learn where the constellations are and which ones you can see during what time of the year. Celestia is like having a planeterium right on your desktop!
Which apps do you use for astronomy and space simulation?