KEO is the name of a proposed space time capsule which was to have been launched in 2003 carrying messages from the citizens of present Earth to humanity 50,000 years from now, when it would re-enter Earth's atmosphere. It was later delayed to 2006, then to 2007/2008, then to 2010/2011, then to 2012, and is currently estimated to launch in 2014.
The project KEO claims to be supported by UNESCO (who it claims voted it "Project of the 21st century"), Hutchison Whampoa, the European Space Agency, and among other institutions. Its name represents the three most frequently used sounds common to the most widely spoken languages today, /k/, /e/, and /o/.
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