ESA's sideways plan to improve space weather forecasting
Problems are easier to deal with if you can see them coming. That's the basis of theEuropean Space Agency's new plan to improve space weather forecasting. ESA is looking to develop a space mission that could for the first time provide us with a "side-view" of the Sun, giving us advance notice of potentially damaging space weather events such as coronal mass ejections (CMEs).
CMEs are significant releases of plasma threaded with magnetic fields from the Sun. Usually following the increased occurrence of solar flares, some of these bursts of magnetic energy have such intensity that they can knock out electrical power grids, affect satellites and disrupt telecommunications – and a single event could cause €15 billion worth of damage in Europe alone according to ESA estimates.
The mission concept floated by ESA would aim to provide a preview of such potentially damaging events by putting an observation craft at the 5th Lagrange point (L5), which lies 60 degrees behind Earth's solar orbit. A spacecraft placed at this point would effectively be able to monitor the sun from the side, spotting dangerous solar activity before that hemisphere of the sun rotates into view.
This would be the first attempt at flying a mission to L5 ever made. Previous missions have only observed extreme solar activity from the visible hemisphere turned towards Earth.
"L5 is an excellent spot for a future ESA space weather mission because it gives advance views of what's happening at the Sun," says Juha-Pekka Luntama from ESA's mission control centre in Germany. "The spacecraft would provide crucial data that will help us spot Earth-arriving ejections, improve our forecasts of the arrival time at Earth and provide advance knowledge of active regions on the Sun as they rotate into view."
Based on the results of ESA's proposal, a final design will be selected for construction in the next 18 months. If successful it would join other Sun-monitoring missions such as NASA's STEREO (Solar TErrestrial RElations Observatory) spacecraft, which involves two probes on opposite sides of the Sun.