“Starshot wants to build the world’s most powerful laser and aim it at the closest star. What could go wrong?”
An anonymous reader quotes MIT’s Technology Review:
In 2015, Philip Lubin, a cosmologist from the University of California, Santa Barbara, took the stage at the 100-Year Starship Symposium in Santa Clara. He outlined his plan to build a laser so powerful that it could accelerate tiny spacecraft to 20% of the speed of light, getting them to Alpha Centauri in just 20 years. We could become interstellar explorers within a single generation. It was quite the hook.
Because Lubin is an excellent public speaker, and because the underlying technologies already existed, and because the science was sound, he was mobbed after the talk. He also met Pete Worden, a former research director of NASA’s Ames Research Center, for the first time. Worden had recently taken over as head of the Breakthrough Initiatives, a nonprofit program funded by Russian technology billionaire Yuri Milner. Six months later, Lubin’s project had $100 million in funding from Breakthrough and the endorsement of Stephen Hawking, who called it the “next great leap into the cosmos.”
Starshot is straightforward, at least in theory. First, build an enormous array of moderately powerful lasers. Yoke them together—what’s called “phase lock”—to create a single beam with up to 100 gigawatts of power. Direct the beam onto highly reflective light sails attached to spacecraft weighing less than a gram and already in orbit. Turn the beam on for a few minutes, and the photon pressure blasts the spacecraft to relativistic speeds.
Not only could such a technology be used to send sensors to another star system; it could dispatch larger craft to Earth’s neighboring planets and moons. Imagine a package to Mars in a few days, or a crewed mission to Mars in a month. Starshot effectively shrinks the solar system, and ultimately the galaxy.
It’s fantastic. And also a dream. Or a sales pitch. Or a long-term, far-out project that can’t be sustained long enough for the nonexistent technologies it requires to be built.