7 November 2002

Microwave Beam To Boost Satellite Into Orbit

by Kate Melville

UC Irvine physicist Gregory Benford will announce plans for the first known attempt to push a spacecraft into the Earth's orbit with energy beamed up from the ground.

Benford will give details on the unique project at the First International Symposium on Beamed-Energy Propulsion (ISBEP) Wednesday, Nov. 6, at the University of Alabama in Huntsville.

The joint UCI-Microwave Sciences Inc. mission will take place next spring, commencing with the satellite launching from a Russian submarine off the coast of St. Petersburg. Benford and his brother, James Benford, the president of Microwave Sciences, will chair two sessions on microwave-powered propulsion during the symposium. They will also answer questions about the upcoming mission at a press conference at 5:30 p.m. CST, on Tuesday, Nov. 5.

The satellite will be called the Cosmos Sail, the first solar-sail craft to orbit Earth. The Benfords developed the sail with researchers from the Jet Propulsion Laboratory. Made from lightweight layers of aluminized mylar, the sail will allow a craft to be propelled from low orbit to high orbit and ultimately into interplanetary space, driven by microwave energy, similar to the way wind pushes a sailboat across the sea.

By using these electromagnetic waves, spacecraft would burn significantly less engine fuel-the most prohibitive expense of interplanetary voyaging.

In describing the launch project, Gregory Benford, a NASA consultant for the Mars Outpost project, said once the spacecraft is at about 800 kilometers altitude, its sail will be deployed. After the craft is flown in its first trials, a microwave beam emitted from the Jet Propulsion Lab's Goldstone 70-meter antennae in California's Mojave Desert will be used to give the spacecraft an extra push. Instruments on board the satellite will measure how much the sail accelerates due to the microwave boost.

While the push received from the Goldstone microwave beam will not be strong, it will be significant, since the spacecraft's mission is to test the feasibility of beam-boosted sails.

"The basic ability to move energy and force through space weightlessly is key to a genuinely 21st century type of spacecraft," Benford said. "This marks a significant attempt to make space travel more effective and cost-efficient."