The KEO satellite is a satellite space time capsule which will be launched in 2009 or 2010 carrying messages from the citizens of present Earth to humanity 50,000 years from now, when the satellite orbiting Earth will return. This project is supported by UNESCO (who voted it Project of the 21st Century), Hutchison Whampoa and the European Space Agency, among other institutions. Its name represents the 3 most frequently used sounds in common to the most widely spoken languages today, [k], [e] and [o]. 
Every person is invited to write a message addressed to the future inhabitants — the deadline is December 31, 2008. Messages can be keyed-in on the web, or sent by postal mail. The organizers encourage everybody to gather messages from children, senior citizens and the illiterate so that every culture and demographic on Earth is represented. The satellite has enough capacity to carry a four-page message from each of the more than six billion inhabitants on the planet. Once the satellite is launched, the messages with personal names removed will be made freely available on the web.
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