The U.S. Space Weather Prediction Center (SWPC) Friday issued a Strong Geomagnetic Storm Watch for Saturday, saying power and communications systems could be affected after a significant solar flare was observed on the sun.
The U.S. space agency NASA’s Solar Dynamics Observatory reported observing a significant solar flare — or "coronal mass ejection" (CME) — Thursday. Flares or CMEs are powerful eruptions on the sun’s surface that send tons of superheated gas and radiation into space. The observatory, which constantly monitors solar activity, captured an image of Thursday’s event.
The bursts of radiation often head toward Earth, and while harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans, if they are strong enough, they can disturb the atmosphere in the layer where GPS and other communications signals travel.
When solar activity could affect day-to-day activity on earth the SWPC, a division of the National Oceanic and Atmospheric Administration (NOAA), issues a watch or warning.
In this case, the center issued a strong, or G3, storm watch for Saturday, indicating the radiation could affect power systems, creating voltage irregularities, interference with communications systems or the operation of spacecraft, such as satellites. The watch is in effect from the North Pole south to the 50th parallel, roughly halfway to the equator.
The prediction center said the aurora borealis — also known as the northern lights — may also be visible Saturday at unusually lower latitudes. It issued a G2 or moderate geomagnetic storm watch for Sunday.
NASA and NOAA have developed the National Space Weather Strategy and Action Plan to help mitigate the effects of solar events. NASA works as the research arm of the nation's space weather effort, using a fleet of spacecraft that monitor the sun's activity, the solar atmosphere, as well as particles and magnetic fields in space surrounding Earth.
NOAA established the SWPC in Boulder, Colorado, to monitor solar activity, much the way NOAA’s National Hurricane Center monitors tropical cyclones. Using NASA’s satellites and solar observatories, SWPC can give forecasts and warnings of solar activity that could impact the Earth.