NASA is preparing to test a small satellite propelled by solar sails. It’ll be interesting to see how the experiment turns out. Solar sails are one of the technologies that has been proposed for use in interstellar travel.
Here’s a Technology Review article on the NASA test:
For the first time, NASA is preparing to send into orbit a small satellite that can be propelled by solar sails. When light particles from the sun strike the surface of the sail, the energy is transferred to it, providing a propulsive force that moves the satellite through space.
NASA’s goal is to test the complex deployment mechanism of the 10-square-meter sails, says Dean Alhorn, an engineer at NASA’s Marshall Space Flight Center, in Huntsville, AL, and the lead engineer on the project. “A successful flight will not only make for a unique historical event, but will show that we have a reliable mechanism to deploy a solar sail in space for future missions,” says Alhorn.
The satellite, called NanoSail-D, is scheduled to launch from Omelek Island, in the Pacific Ocean, on July 29 onboard the Falcon 1rocket developed by Space Exploration Technologies (SpaceX), of Hawthorn, CA. The NanoSail-D satellite’s main frame is only 30 centimeters long and weighs nine pounds. Its solar sail is made of a custom polymer that is thinner than a piece of paper and coated with aluminum to reflect the photons. “It looks like Saran Wrap with a metalized surface but is stronger and suited for the space environment,” says Alhorn.
Update 8/1/08 — Here’s a PhysOrg.com article titled, “A Brief History of Solar Sails” for anyone looking for more information on the subject.