Global positioning system and radio transmissions may be degraded through Saturday as two solar eruptions strike Earth and affect its magnetic field. The U.S. Space Weather Prediction Centre is tracking two two coronal mass ejections, “huge expulsions of magnetic field and plasma” that shot out of an area near the centre of the sun’s disc. “Essentially the sun just shot out a magnet and it is about to interact with another magnet, Earth’s magnet,” William Murtagh,program coordinator of the U.S. Space Weather Prediction Centre, said Thursday. When the ejections reach Earth, they will touch off geomagnetic storms that are forecast to last at least until Saturday. Essentially the sun just shot out a magnet and it is about to interact with another magnet, Earth’s magnet The first wave of the two-part event arrived Thursday night and is forecast to touch off a G2 storm. The second one will arrive about mid-day New York time and with the combined effects of the first one may create a G3 incident. Geomagnetic storms, like hurricanes, are classified on a five-step scale with G1 being the weakest and G5 the strongest. Earth should be spared the most crippling impacts of these kinds of events, which can include disruptions to electric grids and radiation strong enough to cause polar flights to change routes, said Thomas Berger, the center’s director. People away from city lights may see a brilliant display in the northern sky.