Sun storm could affect GPS signals

WASHINGTON: Fast on the heels of a solar storm that delivered a glancing blow over the weekend - triggering bright auroras in Canada and Scandinavia - the sun has released an even more energetic blast of radiation and charged plasma that could disrupt GPS signals and the electrical grid, space weather experts warned.

Already, the storm could be disrupting satellite communications as streams of radiation from the sun bounce across the Earth's magnetic field.

''With the radiation storm in progress now, satellite operators could be experiencing trouble, and there are probably impacts as well to high-frequency communications in polar regions,'' said Doug Biesecker, a physicist at the US Space Weather Prediction Centre in Colorado.

In Australia, the effects are expected to be lighter, as the shockwave hits some time before 9am Wednesday.

''It could cause quite a few problems with shortwave radion, at some frequencies, and the power grid operators have been warned and they can compensate for it,'' Dave Neudegg, the manager of Australia's Ionospheric Prediction Service, said.

Auroras may be visible from southern Australia, including Hobart and possibly Victoria.

The solar storm is the biggest since 2005.