The KEO project aims to launch a satellite into an orbit which will decay over 50,000 years, eventually returning the capsule and its contents to Earth intact.

The capsule will contain what the folks putting together the project imagine will be an archeological treasure-trove for future generations: an astronomical clock; a diamond-encased set of samples (of sea water, fertile soil and human blood [before any genetic engineering], a library (with instructions for decoding), portraits of people from all the major contemporary ethnic groups (since the ethnic make-up of humanity will undoubtedly be completely transformed in 50Ks) and a bunch of messages contributed by supporters.

Like Stewart's Clock of the Long Now, Jaron Lanier's library written in cockroach DNA, or Jamais' Retrospect Project, the real value here is in getting us to think of responsibilities and continuities that extend 50,000 years. After all, when we think of building a future, we ought to be imagining a future that goes on a very, very long time, for simply conjuring the idea of our decendents living here on this planet fifty millennia hence changes the meaning of our lives and actions today.