Chinese scientists persue dreams of solar-powered space flight
A team of Chinese scientists believe they could one day develop a fuel-free spacecraft that would be able fly through deep space using only light from the sun. The team theorizes that such a spacecraft would be made from the wonder material graphene, an atomic-scale honeycomb lattice made of carbon atoms.
First produced and isolated in a laboratory in 2003, graphene is 200 times stronger than steel by weight and conducts heat and electricity extremely well. These flat sheets of carbon just one atom thick are said to be able to turn light into action, which could form the basis of a solar-powered spacecraft, according to the results Chen and Tian published in UK-based scientific journal Nature Photonics earlier this year.
During their three years of research, the team worked with a "graphene sponge," a squidgy material made by fusing crumpled sheets of graphene oxide. While cutting the sponge with a laser, they noticed that the material was propelled forward by the light. Eventually, after experimenting with lasers of different wavelength and intensity, the scientists were able to push the sponges forward by as much as 40 centimenters and even managed to move a graphene sponge with ordinary sunlight through a lens.
Theoretically, a graphene vehicle carrying a load of 500 kilograms would be able to increase acceleration at 0.09 meters per second, Chen said.
"While the propulsion force is still smaller than conventional chemical rockets, it is already several orders larger than that from light pressure," according to the paper, raising the possibility that graphene sponges could be used to make a solar-powered propulsion system for spacecraft that would be significantly more powerful than solar sails.