ESA video on advanced propulsion: "Electric ion engines; plasma drives, slingshot-style gravitational-assist maneuvers; ultra-light super-strong solar sails and other innovations are driving exploration forward beyond reliance on chemical rockets."
--User:Ben 27 May 2009
An article about The Planetary Society's efforts to fly another solar sail demonstration mission - Cosmos 2. Their previous attempt, Cosmos 1, suffered a launch vehicle failure.
--User:Ben 5 May 2009
From Space Travel. Update on The Planetary Society's solar sail activities.
--User:Ben 3 April 2009
On The Space Review
--User:Ben 6 October 2008