Flight patterns

This video shows the tracks of all flights over the U.S. for a couple days in March 2005. The sound is irrelevant and marginally annoying, but the imagery is intriguing. (Posted at Neatorama)

Some other time perhaps I can blog about the weeks in mid-September 2001 when all flights were grounded, the contrails disappeared from the skies, and more sunlight reached the surface of the country.