Setting sail to keep watch for solar storms

2019-03-07 06:02:18

By Duncan Graham-Rowe A SPACECRAFT with a solar sail may be stationed between Earth and the Sun to provide early warnings of solar storms, which can seriously damage phone networks, satellites and power grids. The US National Oceanic and Atmospheric Administration in Washington DC wants to place the solar monitoring station 2 million miles from Earth in 2003. It plans to use a lightweight spacecraft equipped with a solar sail, says Patricia Mulligan, manager of the Geostorms programme, because positioning a craft beyond the libration point, where the gravitational pull of Earth and Sun are equal, is very energy-intensive. “A solar sail would allow us to keep that position,” Mulligan says. The tiny pressure produced by the solar wind keeps solar sails stiff, like sails on a boat. One design competing for the Geostorms job, a 10-kilogram craft called Solar Blade, resembles a helicopter. It has four sail blades, each 20 metres long and 1 metre wide, which can be pitched like a rotor. Richard Blomquist at Carnegie Mellon University in Pittsburgh, who is coordinating the Solar Blade project, believes this design will work because the blades unroll rather than unfold. “The biggest obstacle is that of deployment,