Crowdfunded spacecraft LightSail 2 prepares to go sailing on sunlight

LightSail 2 doesn’t have solar-powered engines, or use solar energy or heat for some secondary purpose; it will literally be propelled by the physical force of photons hitting its immense shiny sail. “In terms of the amount of force that solar pressure is going to exert on us, it’s on the micronewton level,” said LightSail project manager Dave Spencer. Bruce Betts, chief scientist for LightSail, chimed in as well, to make the numbers a bit more relatable: “The total force on the sail is approximately equal to the weight of a house fly on your hand on Earth.”

Source: techcrunch.com