One very elegant way of travelling inside the Solar System is by using a Solar Sail. In such a system, the spacecraft unfurls a large, lightweight sail which reflects light from the Sun or some other source. The radiation pressure on the sail provides thrust by absorbing (for black sail) or reflecting (for reflective sail) photons. In one my previous posts, I talked about a NASA experiment to test a solar sail in a vacuum chamber that will simulate the space environment. Now a more ambitious proposal by The Planetary Society and the Cosmos Studios plans to test a concept Solar Sail (named Cosmos 1) in space within the next few weeks :).

Cosmos 1 (Courtesy: The Planetary Society)The most amazing thing about this project is that it is not funded by any government! Cosmos 1 has 8 triangular sails, each 15 meters (50 feet) in length, configured around the spacecraft's body at the center. The sails will be deployed by inflatable tubes once the spacecraft is in orbit. The spacecraft will be launched from a submerged Russian submarine in the Barents Sea. It will be carried into orbit on board a Volna rocket - a converted ICBM left over from the old Soviet arsenal.
Cosmos 1 will orbit the Earth at an altitude of over 800 kilometers. It will gradually raise its orbit by solar sailing -- the pressure of light particles from the Sun upon its luminous sails. According to the Planetary Society, the launch will take place sometime before May 30 this year.
Perhaps some day, we will see Solar sails transporting supplies between space-stations and planetary bases across our Solar System :):). Hopefully, in our lifetime....