What happens if E.T. phones us?

Four light years — more than 24 trillion miles — from our home planet there is a world orbiting a small, red star called Proxima Centauri. No human eyes have ever seen it. The scientists who announced its discovery Wednesday are pretty sure it exists because they can see the way the star wobbles under the influence of gravity every time the probably-a-planet passes close by.

Astronomers have confirmed the existence of 3,375 exoplanets outside our solar system, and 297 of those are potentially habitable. But “Proxima Centauri b,” as this new one is known, is special. Not only is it tantalizingly close (at least in terms of space distances), it’s also part of a star system that has long played an outsized role in our spacefaring fantasies. That little shiver you feel is your brain hoping that science fiction might, just might, become science fact.

And that made us wonder what might happen if, by some strange luck, Proxima Centauri b were to turn out to harbor signs of intelligent life. Who do scientists tell first? Who decides how we earthlings respond? How does one have a close encounter of the bureaucratic kind?