Washington, June 10 : Scientists have expressed concern about the Sun going through a period of inactivity for the past couple of years, producing no sunspots.
Though it's good news for people who scramble when space weather interferes with their technology, it became a point of discussion for the scientists who attended an international solar conference at Montana State University (MSU) in the US.
Approximately 100 scientists from Europe, Asia, Latin America, Africa and North America gathered June 1-6 to talk about "Solar Variability, Earth's Climate and the Space Environment."
According to the scientists, periods of inactivity are normal for the sun, but this period has gone on longer than usual.
"It continues to be dead," said Saku Tsuneta with the National Astronomical Observatory of Japan, program manager for the Hinode solar mission. "That's a small concern, a very small concern," he added.
Dana Longcope, a solar physicist at MSU, said the sun usually operates on an 11-year cycle with maximum activity occurring in the middle of the cycle. Minimum activity generally occurs as the cycles change.
Solar activity refers to phenomena like sunspots, solar flares and solar eruptions. Together, they create the weather than can disrupt satellites in space and technology on earth.
According to Longcope, the last cycle reached its peak in 2001 and is believed to be just ending now. The next cycle is just beginning and is expected to reach its peak sometime around 2012.
Today's sun, however, is as inactive as it was two years ago, and scientists aren't sure why.
"It's a dead face," Tsuneta said, referring to the sun's appearance.
Though Tsuneta is not sure how long the sun will continue to be inactive, scientists associated with the Hinode mission are ready for it to resume maximum activity. hey have added extra ground stations to pick up signals from Hinode in case solar activity interferes with instruments at other stations around the world.
The new stations, ready to start operating this summer, are located in India, Norway, Alaska and the South Pole.