Although launch is still months away, plans to fly the world's first solar sail are progressing closer to liftoff as the Planetary Society-led Cosmos 1 team conduct a flurry of tests to ensure a successful flight.

Engineers have recently redesigned some parts of the craft to increase the mission's capabilities and to reduce the chances for failure.

"The spacecraft is far more capable than the one we had originally planned," said The Planetary Society's Executive Director, Louis Friedman. "Much more redundancy and capability have been built into it."

One of the most recent tests involved the deployment of a single 50-foot solar sail blade on the spacecraft mechanical model in a vacuum chamber at a testing site at the NPO Lavochkin factory in Russia. The solar sail to be placed into orbit will include eight such blades, forming a circular pattern with a diameter of about 100 feet.

Solar sail deployed in the vacuum test chamber at NPO Lovochkin. Photo: (c) Louis Friedman and The Planetary Society

This latest test included the first use of a new deployment system that folded the blades when stowed. Earlier designs had used blades that were rolled up prior to deployment.

"The blade deployed from the new configuration very smoothly," said Victor Kudryashov, Cosmos 1 Project Manager at the Babakin Space Center, who is in charge of the construction of the spacecraft. "We will, of course, continue to analyze the test data."

Cameras provided by Ecliptic Enterprises -- the company who provides the equipment to produce the dramatic "rocketcam" videos -- recorded the deployment test inside the chamber. Cameras will also be installed on the Cosmos 1 spacecraft during the mission to record solar sail activities.

"Seeing that four-story-long blade deploy in vacuum was a thrill," Friedman said. "Still ahead of us is the extraordinary adventure and drama of unfurling the sail in the zero gravity conditions of orbit."

The solar sail blade test was just one of many recent tests on the mechanical model of Cosmos 1. Officials say that testing of the electrical and electronics systems should get underway soon at the Space Research Institute of the Russian Academy of Sciences. If all goes as planned, the tests on the mechanical and electrical models should wrap up by summer's end.

The schedule calls for processing of the actual flight hardware in September and October, followed by a launch late this year at the earliest. A firm launch date will not be selected until the tests are complete, The Planetary Society said in a statement.

The orbital Cosmos 1 mission has been delayed for more than a year from the original target timeframe of late 2001. The failure of a suborbital test flight in July 2001 forced the first schedule slip, then a winter blizzard forced a delay in the manufacturing of critical components of the spacecraft. The Russian center in charge of building the craft then opted to change the design of parts of the Cosmos 1 solar sail, whereby reliability was to be increased, but the launch date was once again forced to move back to the current target of late this year.

Cosmos 1 is a joint undertaking by The Planetary Society and Cosmos Studios, with the Russian Babakin Space Center and other organizations in charge of manufacturing and testing.

The mission is the first flight of a solar sail, which utilize blades made of light-weight material to allow light pressure from the Sun to be used as a means of propulsion. This type of spacecraft design is especially attractive for use in interplanetary missions.

Officials will monitor the orbital parameters of the craft to see if light energy increases the speed and height of the orbit, a sign that the concept works as expected.

"We believe this basic spacecraft design could even serve as an interplanetary spacecraft, for example a mission to Mars," said Dr. Viacheslav Linkin, Cosmos 1 Chief Scientist.

"This is precisely the dream we had in mind when we funded this mission," explained Ann Druyan, Cosmos Studios CEO, "to support the development of a whole new mode of space exploration."