““Consider this: in February of 1966, the Soviet Union soft-landed a space probe on the moon. Humanity has been launching programs ever since. NASA launched Voyager 1 in September of 1977. In 2012 it became the first satellite to reach interstellar space. At some point, Voyager will fall into the gravity well of a planet, or asteroid, or even another planet’s moon. Possibly a black hole. The point is that it will crash somewhere—maybe on a place like our moon, but orbiting another planet, very far away.” Yuri smiled. “And if that’s true, then why has it not happened here—on our moon, which is over four and a half billion years old? The greatest mystery in the world is why our moon isn’t covered with space junk.” “Space junk?” “Interstellar probes—like Voyager 1—from other sentient species across the universe, launched long before we evolved, launched long before there was even life on our world.””
