Solar flare warning system may be coming

It may one day be possible to forecast solar flares, protecting satellites, power grids and astronauts from potentially harmful radiation, U.S. researchers say. Scientists at Purdue University say the system would work by measuring differences in gamma radiation emitted when atoms in radioactive elements decay, or lose energy, a deterioration long thought to be constant but now believed to vary with solar activity. They say they believe radioactive decay rates on Earth are influenced by solar activity, possibly streams of subatomic particles called solar neutrinos. Researchers are studying the phenomenon with the hope of possibly developing a warning system, a university release reported Monday. Purdue researchers in both physics and nuclear engineering have been examining variations in decay rates of isotopes that occur before solar flares. "It's the first time the same isotope has been used in two different experiments at two different labs, and it showed basically the same effect," physics Professor Ephrain Fischbach said. "We have repeatedly seen a precursor signal preceding a solar flare. We think this has predictive value."