For centuries sailors have used stars to navigate around the world. Now space-sailors might be able to use the stars to move through the universe — literally! Instead of cruising to Mars on a giant tank of oil, we could soon sail through space using just the energy from sunlight. The Planetary Society — a non-profit space exploration organization — just announced that in 2010 it will send a satellite dubbed LightSail-1 into space that will be propelled by solar sails. The mylar-winged vessel will carry not a drop of fuel (making it much lighter than contemporary space craft) and will be the first in a three part program that aims to prove that solar sailing is a viable technology
The LightSail-1 is a solar sail propelled satellite that will travel through space using only the energy contained within the sun’s rays. To do this the craft features 4 triangle-shaped aluminized Mylar sails that are capable of capturing the momentum of light emitted by the sun. When the photons in these light rays hit the sails on the LightSail-1 they will transfer the momentum they carry to propel the craft into space, much like wind transfers momentum to the sails on a sailboat.
LightSail-1 will weigh about 11 pounds, and when its sails are opened they span 6 meters across. It consists of three small cubes – two cubes hold the sails and one that holds the controls and electronics. The solar sailing craft will stay pretty close to Earth, traveling only a few miles after being released 500 miles above the surface of the planet, but each consecutive mission will sail further into space.
Scientists think that the possibility of carrying a person on a LightSail craft is a long way off and will involve technology not yet developed — they estimate a human on board would necessitate sails about a mile wide — but the hope for the future is bright. The distance we can travel in space has always been limited by the ability of spacecraft to carry enough fuel, so a craft capable of moving using only the sun’s rays could send space travel into a non-oil dependent future and open up the realm of deep space exploration.
The Planetary Society is hoping to hitch a ride into space on an already planned mission with a US or Russian spacecraft at the end of next year. Being a pretty light load, it seems like an easy carpool request.
Via New York Times
What an excellent idea!
The only problem i can see is that it will not be very resistant to debris.