Solar super-sail could reach Mars in a month New Scientist

A LICK of paint could help a spacecraft powered by a solar sail get from Earth to Mars in just one month, seven times faster than the craft that took the rovers Spirit and Opportunity to the Red Planet. Gregory Benford of the University of California, Irvine, and his brother James, who runs aerospace research firm Microwave Sciences in Lafayette, California, envisage beaming microwave energy up from Earth to boil off volatile molecules from a specially formulated paint applied to the sail. The recoil of the molecules as they streamed off the sail would give it a significant kick that would help the craft on its way. “It’s a different way of thinking about propulsion,” Gregory Benford says. “We leave the engine on the ground.”