Sun is constantly changing going through cycles of seasons peaking by every 11 years, said new research that says even a shorter time cycle, with activity waxing and waning over the course of about 330 days, do occur.
Scientists are trying to understand when to expect such bursts of solar activity and to successfully forecast the sun’s eruptions, which can drive solar storms at Earth. The Solar space condition affects the satellites, GPS navigation, and radio communications.
The quasi-annual variations in space weather, scientists say, is driven by changes in bands of strong magnetic field on each solar hemisphere. Their paper was published in Nature Communications April edition.
“What we’re looking at here is a massive driver of solar storms,” said Scott McIntosh, director of the High Altitude Observatory of the National Center for Atmospheric Research in Boulder, Colorado. “By better understanding how these activity bands form in the sun and cause these seasonal instabilities, we can greatly improve forecasts of space weather.”
Several studies of late have been focusing on examining what creates the magnetic bands and how they influence solar cycles.
McIntosh team detected the bands by observing via NASA satellites and ground-based observatories watching the sun and its constant flow of particles in the solar wind to large explosions such as solar flares or giant eruptions called coronal mass ejections, or CMEs.
The scientists note that the changes in the 330-day activity cycle on the sun that is observable but has often been downplayed and overlooked when trying to look at the cause of the 11-year cycle.
“People have not paid much attention to this nearly-annual cycle,” said McIntosh. “Cycles over this time frame are observed in all sorts of output from the sun: the sun’s radiance, the solar wind, solar flares, CMEs.”