Image copyright NASA Image caption A giant wave of energy is headed towards Earth
NASA is issuing a call for a geomagnetic storm watch after a spectacular solar flare.
The US space agency has said it is looking at sending a minor-league jet to Earth in mid-October to monitor a developing storm.
Space weather forecasters with the National Oceanic and Atmospheric Administration said a moderate storm was expected in November.
Solar flares can knock out GPS and radio signals. The waves can knock power grids offline for days.
Image copyright NASA Image caption In September 2011, a solar storm knocked out the power grid for tens of thousands of people in Quebec, Canada
Solar flares are gigantic explosions of radiation.
They generate powerful blasts of electromagnetic radiation and intense magnetic fields in the magnetosphere that surrounds the Earth.
The National Oceanic and Atmospheric Administration (NOAA) said it was estimating a “moderate geomagnetic storm” on the order of one or two days, accompanied by the effects of a Category 2 jet.
Image copyright NASA Image caption The classic Earthwide aurora borealis can be seen in October
In 2011, a large solar flare knocked out communications and power grids across North America. Tens of thousands of people in Quebec were left without power.
This September saw another large flare and NASA has calculated that the damage would be limited if the storm was on the order of that in 2011.
The US space agency put it down to the planet’s magnetic field building up “cooling up” from the event, allowing the strong energetic particles to go away before hitting the ground.
Only the storms that do occur are life-threatening.
Earth gets a geomagnetic storm watch every October or November, as the planet’s geomagnetic field is exposed to stronger radiation coming from the sun.
But for most of Earth’s surface, the storms are treated as a nuisance, with the electromagnetic waves simply changing frequencies for the radio, according to NASA.
But for some parts of the planet it can have a serious impact on the frequency of radiation arriving in the Earth’s atmosphere.