Every year, the Canada Centre for Remote Sensing collects and archives 30 terabytes of satellite imagery. As of March 2000, this has added up to a total of 275 terabytes!

One terabyte is equal to:

• 1,024 gigabytes, or
• 1,048,576 megabytes, or
• 1,073,741,824 kilobytes, or
• 1,099,511,627,776 bytes.

How much is that? Well, if you can put about 640 megabytes of data onto one compact disk (CD), then it would take 430,000 CDs to store all the information the CCRS archive has collected so far. If you placed those CDs side by side, then they would span 51.6 km. That's about the distance from Charlottetown to Summerside, or from Dorval airport to St. Hubert, or from North Vancouver to the Gulf Islands. If you stacked those 430,000 CDs on top of each other (don't try this at home!), it would reach the approximate height of the CN tower. In other words, that's a LOT of data!