Nasa's Hi-C rocket experiment captures unprecedented view of solar flares

NOAA Issues Rare , Warning Following Powerful , Solar Event. CBS reports that a severe G4 geomagnetic storm headed towards Earth has triggered a rare warning from NOAA officials for the first time in two decades. The warning comes following days of solar activity that sent several waves of plasma in Earth's direction along with powerful magnetic fields. G4 storms are the second-strongest type of geomagnetic storms and can cause widespread voltage problems. . NOAA warns that they can also cause some protective assets to "trip out key assets from the grid," as well as cause orientation problems for spacecraft. . If geomagnetic storms were hurricanes, 'severe' would be category 4. , Spaceweather.com, via CBS. The powerful G4 storm could also cause northern lights, or aurora borealis, to be seen in northern California and as far south as Alabama. In a May 9 press release, NOAA said that the solar event began on May 8, when a group of sunspots generated "several moderate to strong solar flares.". According to NASA, solar flares are explosions of radiation which are considered the strongest explosive events in the solar system. NOAA noted that the area, which produced the recent flares, is roughly 16 times the diameter of the Earth. The sunspots known as AR3664 measures about 124,000 miles across, and Space.com notes that it is one of the, "largest and most active sunspots seen this solar cycle." . According to NOAA, the geomagnetic storm is expected to hit Earth as early as midday on May 10 and continue through May 12