Arthur C. Clarke (1917–2008) British science fiction writer, science writer, inventor, undersea explorer, and television series host
"The Sentinel" (1948), originally titled "Sentinel of Eternity" this is the short story which later provided the fundamental ideas for 2001: A Space Odyssey (1968) written by Clarke and Stanley Kubrick.
1940s
Context: I can never look now at the Milky Way without wondering from which of those banked clouds of stars the emissaries are coming. If you will pardon so commonplace a simile, we have set off the fire alarm and have nothing to do but to wait.
I do not think we will have to wait for long