Post by michaellazizza on Mar 10, 2006 11:08:31 GMT -5
Science 10 March 2006:
Vol. 311. no. 5766, p. 1357
DOI: 10.1126/science.311.5766.1357
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News of the Week
SOLAR PHYSICS:
The Sun's Churning Innards Foretell More Solar Storms
Richard A. Kerr
Astronauts, power grid operators, and satellite managers had better watch out in 2012, a group of solar physicists warns. Drawing on their computer simulation of the circulation in the sun's interior, researchers at the National Center for Atmospheric Research (NCAR) predict that the next peak in sunspots will come a little late but will be far bigger than the last peak--bigger, in fact, than all but one of the 12 solar maxima since 1880. The accompanying solar storms could play havoc with satellite communications and threaten space station astronauts.
The key to predicting solar activity years ahead, according to solar physicists Mausumi Dikpati, Peter Gilman, and Giuliana de Toma, is including data from enough past sunspot cycles. Every 11 years, the sun's dark spots and accompanying flares wax and wane. Predictions based on just the present strength of the magnetic field near the sun's poles--that is, the lingering remnants of the previous cycle's sunspots--call for an especially weak sunspot cycle coming up.
Onward and upward. Solar physicists are predicting that the next peak in sunspots and other disruptive solar activity will exceed the previous solar max (squiggly line) because the previous three peaks contribute.
CREDIT: NASA/MSFC/HATHAWAY
But the NCAR group, located in Boulder, Colorado, thought that several past cycles might influence the coming one. When they ran their new model of the solar interior, they fed it with observations since 1880 to see how past cycles might assert their influence. They found that it takes a good 20 years for the magnetic remnants of past sunspots to recirculate deep into the interior, where the twisting action of the sun's rotation amplifies them, and to rise back to the surface near the equator as the next cycle's sunspots. The model did an impressively accurate job "hindcasting" the size and timing of past cycles. That track record made Dikpati confident that "the next solar cycle will be 30% to 50% stronger than the last solar cycle," she told a media teleconference this week. The next cycle will begin 6 to 12 months later than average, in late 2007 or early 2008, according to the model, and will peak in 2012.
The model-based prediction "is exciting stuff, the first new thing to come along" in decades, says Ernest Hildner, the recently retired director of the Space Environment Center in Boulder, the federal group charged with forecasting solar activity. It's especially exhilarating because "it finally answers the 150-year-old question: What causes the sunspot cycle?" solar astronomer David Hathaway of NASA's Marshall Space Flight Center in Huntsville, Alabama, told the teleconference. New work by Hathaway and colleagues supports the NCAR group's findings.
If the sun is indeed gearing up for an especially active maximum, managers of everything from the Global Positioning System (which solar storms can disrupt) to low-orbiting satellites (which storms can drag down) could begin taking the threat into account. But as exciting as the forecast is, promising techniques for predicting the future have failed before, Hildner points out: "You still have to wait and see."
A little prove that we are not insane, somehow are cells already know that
