Status of solar sail spacecraft uncertain

A spacecraft propelled by sunlight instead of rocket engines launched on Tuesday, but it's unclear if the test flight was a success, Russian space officials said.

Like a sailboat, Cosmos 1 has large, flat surfaces designed to catch packets of light, or photons, from the sun. Theoretically, the photons will provide a light but constant pressure that pushes against the sails to drive the spacecraft forward.

The privately funded $4-million experiment aims to prove that solar sailing can in fact work.

Cosmos 1 launched from a Russian submarine under the Barents Sea at 3:46 p.m. EDT. Plans called for the craft to separate from a booster rocket 45 minutes after launch, although scientists said they can't say for certain that it did so.

The spacecraft has eight sails that are supposed to unfurl to form a reflective surface 30 metres in diameter.

Louis Friedman, president of the society and director of the project, first proposed the idea of a solar sail ship in the 1970s when he worked for NASA.

Ann Druyan, widow of astronomer and writer Carl Sagan, provided most of the funding for Cosmos 1. Sagan died in 1996.