This NASA spacecraft will set sail propelled entirely by sunlight

It took NASA’s Voyager I probe 35 years to reach the edge of our solar system and enter interstellar space. But a lot has changed in space technology since Voyager launched in 1977. NASA’s new space sail—propelled only by the sun—can make that same trip in 20 years.

http://qz.com/610073/this-nasa-spacecraft-will-set-sail-propelled-entirely-by-sunlight/