If there are human beings on Earth in the year 52,001, and they happen to look to the northern sky one evening and find it filled with a shimmering aurora, they can thank Jean-Marc Philippe for the light show. Philippe, an artist in Paris, is the creator of KEO, a satellite designed to stay in orbit for 50,000 years. When KEO finally plunges back into the atmosphere, an ice age or so from now, its disintegrating heat shield will generate spectacular streamers of light--"to alert our descendants that something abnormal has happened," says Philippe. As the northern lights fade, KEO's core, a small titanium sphere, will fall to Earth somewhere, intact. Inside will be letters from us.
Philippe hopes to collect billions of letters, store them on compact disks in that titanium sphere, and launch them in 2001. Because KEO is meant to be a work of art, it will ...