“A habitable, rocky planet around Proxima would be the most natural location to where our civilization could aspire to move after the sun will die, five billion years from now,” says Avi Loeb of the Harvard-Smithsonian Center for Astrophysics and an adviser to the Breakthrough Starshot project.

Even before today’s announcement, Breakthrough Starshot had announced its plan to send tiny spacecraft to the Alpha Centauri system later this century. But don’t expect any postcards from the new planet anytime soon: It will take more than 20 years for a spacecraft traveling at a monstrous 20 percent of the speed of light to reach Proxima Centauri, and another 4.24 years for any data to arrive back on Earth.