BOULDER — A pair of massive solar flares that erupted from the sun's surface Tuesday at about 5 p.m. Colorado time are expected to slam into the Earth early Thursday morning, possibly affecting communications and power, according to the Space Weather Prediction Center in Boulder.

The two X-class flares erupted within about an hour of each other, and they're now screaming toward Earth at speeds of at least 1,100 miles per second, according to NASA. When the flares arrive, they're expected to further agitate Earth's magnetic field, which is already being affected by a solar flare that occurred Sunday.

"Things are already disturbed, and we're going to pound on them some more with another shot from the sun," said Joe Kunches, a scientist at the National Oceanic and Atmospheric Administration in Boulder, where the Space Weather Prediction Center is housed.

The resulting geomagnetic storm has the potential to disrupt high frequency radio communications, global positioning systems and power grids.

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