'Brightpoints' Reveal Inner Workings of Sun's Solar Cycle

The Sun's "brightpoints" serve as new markers for determining the mysterious and ever-changing solar cycle of our closest star, according to a new study, changing scientists' previous beliefs about what drives this cycle.

Approximately every 11 years, the Sun undergoes a complete personality change, from quiet and calm to violently active. The height of its activity, known as the solar maximum, can be observed by numerous sunspots on its surface and solar particles shooting out into the far reaches of space.

Since records began, successive solar maxima have been observed as short as nine years, and as long as 14. Until now, scientists did not know how to more accurately determine the timing and cause of these solar events.

Brightpoints - little bright spots in the solar atmosphere that allow us to observe the inner workings of the Sun - provide a new way to witness the magnetic fields evolve and move through our closest star.

"Sunspots have been the perennial marker for understanding the mechanisms that rule the Sun's interior," Scott McIntosh, a space scientist at the National Center for Atmospheric Research in Colorado, said in a NASA news release. "Now we can see there are bright points in the solar atmosphere, which act like buoys anchored to what's going on much deeper down. They help us develop a different picture of the interior of the Sun."

McIntosh and his colleagues, using data from the joint European Space Agency, and NASA's Solar and Heliospheric Observatory and Solar Dynamics Observatory (SDO), monitored how the last solar cycle progressed and the current one started.

Like sunspots, the researchers found that brightpoints - spots of extreme ultraviolet and X-ray light dubbed as g-nodes - gradually moved closer and closer to the Sun's equator as the solar cycle progressed.

From this, McIntosh and his team determined that the solar cycle, from start to finish, takes about 19 years on average, but is seen to vary from 16 to about 21 years.

Based on these findings, the researchers predict that the next solar cycle will start towards the end of the year 2017, with the sunspots of the next cycle appearing near the end of 2019.

Though the theory has yet to be conclusively proven, it serves as a new way to explore the drivers of solar activity beyond sunspots alone, allowing scientists to create better models of the Sun's activity, as well as the activity of other stars in the Universe.

The findings were published in The Astrophysical Journal.