A Tennessee lawmaker has proposed a new bill that aims to prevent people from using food stamps to purchase items that have no nutritional value, s
Graphene could be used to create fuel-free spacecraft
According to researchers, graphene could be used to create fuel-free spacecraft that works using sunlight. As per reports, these sheets of carbon one atom thick can convert light into action and this could be the foundation of a fuel-free spacecraft. Flat structure of graphene is quite strong; it is a very good conductor of electricity and heat.
Yongsheng Chen from the Nankai University in China and his colleagues were working to find out if larger arrangements of carbon can have some of these properties. Chen along with his colleagues published details of a 'graphene sponge'; it is a material created by fusing crumpled sheets of graphene oxide. They observed that the light pushed the material forwards, when graphene sponge was cut with a laser.
This thing was considered strange since the sponge was a few centimetres across, when lasers were used to shove single molecules. Lasers of different wavelength and intensity were shot at graphene sponge pieces that were placed in vacuum.
They were able to push sponge pieces upwards by as much as 40 centimetres. They even managed to move graphene by focusing ordinary sunlight on it with a lens. According to 'New Scientist', photons can move momentum to an object and push it; this small effect can increase thrust required to move a spacecraft in the vacuum of space.
According to researcher Yongsheng Chen and colleagues of the discovery, "While the propulsion force is still smaller than conventional chemical rockets, it is already several orders larger than that from light pressure".