lightsails

The bright star on the left, Alpha Centauri, is in fact two stars close together: Alpha Centauri A and B. A much dimmer star, circled in red, is Proxima Centauri and is thought to be orbiting the A/B pair. The bright star on the right is Beta Centauri, considered to be a separate stellar system. Credit: Skatebiker/Wikimedia Commons, CC BY-SA 3.0

Starshot, a Billionaire’s New Mission to Get to Alpha Centauri in 20 Years