Downloading a copy

What's the Difference is freely available on both PC and Mac.

PC Version (here)
Mac Version (here)

Solar System Explorer (old version)

PC Version (here)
Mac Version (here)

Recommended Specifications
for What's the Difference

• Mac OSX, Windows: 98, 2000, or XP
• Powerbook G4 or Intel Pentium 3, Celeron or AMD Athlon
• 256 MB of RAM
• 500 MB of disk space
• Apple Quicktime

What's the Difference Notes

     What's the Difference benefits most from a faster CPU and takes advantage of sound. Your machine should be okay if has been purchased within the past three years.

     What's the Difference requires Quicktime to be installed. If you don't currently have it installed, look inside What's the Difference's package under the folder named "quicktime" inside are the install files for both PC and Mac.

     What's the Difference comes with a few samples of comparing planets, however the previous version has a more comprehensive variety of comparison of planets but lack the editing abilities. Eventually these features will be incorporated into the current one. Meanwhile, this older version is made available.

Updates & Patches

     There are no updates or patches at this time.

	What's The Difference is developed at NASA Ames Research Center by Geoffrey Bruce and project manager Christina O'Guinn.