The first voyager to another star may be a worm or a tardigrade

SPACE is cold. So, when launching dogs for early space missions, Soviet rocket scientists chose strays like Laika that had survived on the streets during Moscow’s freezing winter. Today, in contrast, some researchers working on an ambitious effort to dispatch craft to Alpha Centauri, the nearest solar system to Earth’s, see the chill of space not as a hindrance to sending life from one such system to another, but rather as a way to do just that.

Alpha Centauri is an attractive target. It is a cluster of three stars and at least one planet that is only about four light-years away. With money from NASA, America’s space agency, and others, the Experimental Cosmology Group at the University of California, Santa Barbara, is designing a system, called Project Starlight, that proposes to use a powerful laser beam to push fleets of lightweight spacecraft, each the size of a DVD, to a fifth of the speed of light.