A

David

Darling

Cosmos 1 (solar sail)

Cosmos 1 space sail

Cosmos 1 was an experimental solar sail built for the Planetary Society in Russia by the Babakin Space Center and funded by Cosmos Studios, a science-based media and entertainment venture set up by Ann Druyan (wife of the late Carl Sagan) and A&E Network. When opened out, the 600-square-meter sail, made of 5-micron aluminized Mylar, is in the shape of eight roughly triangular blades. The first attempt to deploy it, on a suborbital flight on 20 July 2001, failed. It was carried aboard a 100-kilogram spacecraft launched from a submerged Russian submarine in the Barents Sea on a Volna, a converted submarine-launched ICBM now being marketed for commercial use. Imaging systems aboard the spacecraft are designed to show if the sail deploys, using an inflatable tube system to which the sail material will be attached, as planned. Unfortunately the spacecraft failed to separate from the third stage of the rocket, and as a result the sails and the reentry capsule didn't deploy. The capsule continued on its ballistic flight to the Kamchatka peninsula but was not recovered. A second attempt to deploy Cosmos 1 from a Volna rocket, this time in a near-circular 850-km orbit with an inclination of 78°, took place on 21 June 2005. However, this again ended in failure because of a problem with the first stage of the launch vehicle some 83 seconds into the flight.