NASA to Launch World's Largest Solar Sail in 2014

The largest solar sail ever constructed is headed for the launch pad in 2014 on a mission to demonstrate the value of "propellantless propulsion"— the act of using photons from the sun to push a craft through space.

Dubbed Sunjammer, the giant solar sail measures about 124 feet (38 meters) on a side and boasts a total surface area of nearly 13,000 square feet (1,208 square m, or one-third of an acre). The project is under the wing of NASA's Space Technology Program, within the agency's Office of the Chief Technologist.

NASA has contracted with a team of high-tech "solar sailors" at L'Garde Inc. of Tustin, Calif., to build Sunjammer. L'Garde is no newcomer to novel space structures. The company has worked with the space agency on several projects, including the creation of inflatable structures for radio frequency antennas and solar arrays. In 1996, the company flew the Inflatable Antenna Experiment (IAE) aboard the space shuttle Endeavour's STS-77 mission.

Programmatic milestone

"We took the name Sunjammer from an Arthur C. Clarke short story, a fictional yacht race in the heavens using solar sails," said Nathan Barnes, L'Garde's chief operating officer and executive vice president, as well as Sunjammer's project manager. Permission to use the name came from the Clarke estate, he told
Work on Sunjammer this year includes a programmatic milestone — a critical design review — along with a variety of ground demonstration tests and qualification of components, Barnes said. The flight of the solar sail, he said, is set for the end of 2014, to be sent spaceward atop a SpaceX Falcon 9 rocket.

"With this sail, we’re targeting our end goal somewhere in the neighborhood of 1,864,114 miles (3 million kilometers) distance from the Earth," Barnes said.

A number of test objectives are to be checked off within the first couple months of flight, he added. These include deployment of the sail, demonstration of vector control using sail-tipped vanes, navigation with accuracy and, finally, maintenance of the spacecraft's position at a gravitationally stable location called Earth-Sun Lagrange Point 1.

Sunjammer won't be the world's first solar sail mission. NASA launched NanoSail-D, whose sail covered just 100 square feet (9.3 square m), in November 2010. And Japan's Ikaros probe deployed its solar sail in June 2010, becoming the first craft ever to cruise through space propelled only by sunlight.