London, Oct 14 : Scientists have detected new spots breaking out on the face of the Sun, which may signal the end of a dry spell in solar activity.
Sunspots are cool, planet-sized areas on the Sun where magnetic fields punch through the star's surface.
The number of sunspots rises and falls on an 11-year cycle, along with flares and other solar activity.
The Sun began a new cycle this year, and solar physicists have been waiting for new sunspots to emerge to track the cycle's progress. The faster sunspots return, the more severe solar weather will be in the coming decade.
But since the beginning of 2008, the Sun's face has been virtually spot-free.
According to a report in New Scientist, on October 11, a new spot erupted, the third to have emerged in the last three weeks.
"We're even looking at a possible fourth one that we can see in Stereo B spacecraft images," said Doug Biesecker of the National Oceanic and Atmospheric Administration Space Weather Prediction Center in Boulder, Colorado, US.
The sunspots' appearance could mark the end of a period of extremely low activity on the Sun.
Researchers are still counting sunspots to pinpoint the low point in the cycle, called solar minimum, but early data suggests it may have occurred in March, according to Biesecker.
"At the moment, March 2008 shows the smallest number of sunspots for this phase of the cycle and is a very likely candidate for solar minimum," he told New Scientist. That is, so long as this month and the next few months show at least moderate amounts of activity," he added.
Watching for more spots in the coming months could help determine how severe - and potentially damaging to Earth's satellites and power grids - the next solar cycle will be.
More spots are expected to appear in the coming months. Tracking their rise could help distinguish between competing solar models.
Experts are split on whether to expect a bumper crop of sunspots or an exceptionally small yield.