four-quadrant solar sail propulsion system

Engineers at NASA have designed and built NanoSail-D, a "solar sail" that will test NASA's ability to deploy a massive but fragile spacecraft from an extremely compact structure. Much like the wind pushing a sailboat through water, solar sails rely on sunlight to propel vehicles through space. The sail captures constantly streaming solar particles, called photons, with giant sails built from a lightweight material. Over time, the buildup of these particles provides enough thrust for a small spacecraft to travel in space.

One of NanoSail-D's several mission objectives is to demonstrate the capability to deploy a large sail structure from a highly compacted volume without recontacting the spacecraft. The mission also will demonstrate and test the de-orbiting capabilities of solar sails.

On Thursday, Aug. 19, principal investigator NanoSail-D, Dean Alhorn, at NASA's Marshall Space Flight Center in Huntsville, Ala. answered your questions about the NanoSail-D mission and solar sails in general.