I had the pleasure of learning about a free program named Celestia. The program renders models of the solar system with great accuracy. You can choose a point in time and view a depiction of how certain events would appear from space or from the surface of a planet.
The program is very accurate . . . but not necessarily perfect. But, hey, I'm no astronomer or physicist, so as far as I'm concerned, it's good enough for my purposes.
Celestia can depict events in real time or you can re-play time and events in backwards motion. You can speed time up or traverse light years across the galaxy in an instant.
Shortly after learning about Celestia, I saw a picture of Saturn taken by the spacecraft Cassini. Then, I got an idea . . . why not plug in the date and time of Cassini's take off and watch it's journey. Then, I can compare the photo's perspective with Celestia's simulated perspective.
Cassini's trip to Saturn took seven years! So, I had to speed the time up a lot. But lo and behold, when the program reached the time stamp of that picture I saw . . . the perspective was nearly the same!
Impressive. Most impressive.
This universe is so big and vast. Space is dreadfully beautiful and terribly awesome after letting the concepts soak in and take root. Just as atoms and cells make up who we are, our planets and moons are like atoms and cells to this great universe.
No wonder we have religion and god. We need something to explain all of this -- this inexplicable wonder and vastness that so captivates us and frightens us.
If you're any sort of star gazer, download Celestia. This wonderful program is available for Windows, Mac, and Linux. If Celestia doesn't run well after your first install it, try installing older versions of Celestia until one works. Also, consider making a quick check to see if your PC can meet the system requirements.
And remember . . . this program is free!