Seria include scrisori expediate de: Buzz Aldrin, Isaac Asimov, Carl Sagan, Iuri Gagarin, Ann Druyan, Stanley Kubrick, Alexander Graham Bell, Neil deGrasse Tyson si multi altii.
Seria include scrisori expediate de: amiralul Nelson, Alexander Hamilton, Kurt Vonnegut, Mahatma Gandhi, Mark Twain si multi altii.