Arianespace has announced that they will be launching a cluster of 50 nanosatellites in 2007 to commemorate the 50th anniversary of the first satellite launch of Sputnik in 1957. Each tiny satellite will weigh only 1 kg (2.2 lbs), and contain a scientific package developed by a single country - all 50 will be launched at the same time, on one rocket. The nanosats will last in orbit for about 2 years.