Pioneer 10 spacecraft launched from Cape Kennedy on March 3, 1972.

"At this very moment the messages from another civilization may be wafting across space,

driven by unimaginably advanced devices, there for us to detect them...perhaps the messages

are already here, present in some everyday experience...Consider, for example, seashells."

                                                     --- Carl Sagan, The Cosmic Connection

Sound of waterfall

Mountain

A hollow shell