Thousands of colonists might live on this interstellar Mayflower for a journey lasting generations. The ship has its own ecosystem and artificial gravity from its rotating cylindrical hull. A sister ship looms in the giant window.
This 3,400-square-foot Mylar solar sail was tested in 2005 in a vacuum chamber at NASA’s Plum Brook Station in Sandusky, Ohio. NASA plans to launch Sunjammer, a probe with a sail four times as big, on a yearlong cruise toward the sun in 2014.