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Lower Solar Activity Linked to Changes in Sun's Conveyor Belt
The sun goes through cycles that last approximately 11 years. These solar cycle include phases with more magnetic activity, sunspots, and solar flares. They also include phases with less activity.
The level of activity on the sun can affect navigation and communications systems on Earth.
A team of scientists have studied the solar cycle that ended in 2008, which is known as solar cycle 23. This solar cycle was longer than normal, and the scientists think that one reason could be a stretching of the sun's conveyor belt. This is a current of plasma that circulates between the sun's equator and its poles.
Just as Earth's global ocean circulation transports water and heat around the planet, the sun has a conveyor belt in which plasma flows along the surface toward the poles, sinks, and returns toward the equator, transporting magnetic flux along the way.
The study was conducted by Mausumi Dikpati, Peter Gilman, and Giuliana de Toma, all scientists in the High Altitude Observatory at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, and by Roger Ulrich at the University of California, Los Angeles.
They used simulations to model how the solar plasma conveyor belt affects the solar cycle. They found that the longer conveyor belt and slower return flow could have caused the longer duration of cycle 23.
The results of this study should help scientists better understand the factors controlling the timing of solar cycles and could lead to better predictions. It can also allow us to be prepared for space weather.