CNN reports that Pioneer 10, the first space craft to venture out of our solar system and the one that sent back all of the wonderful photos of Jupiter, has sent its last signal. It is more than 7.6 billion miles from Earth and its 21-month mission has continued for almost 31 years. Pioneer 10 has always held a special place in my heart because it was launched only a few months after my birth. [via Boing Boing]