Two Weeks in the Life of a Sunspot

Typography

On July 5, 2017, NASA’s Solar Dynamics Observatory watched an active region — an area of intense and complex magnetic fields — rotate into view on the Sun. The satellite continued to track the region as it grew and eventually rotated across the Sun and out of view on July 17. 

On July 5, 2017, NASA’s Solar Dynamics Observatory watched an active region — an area of intense and complex magnetic fields — rotate into view on the Sun. The satellite continued to track the region as it grew and eventually rotated across the Sun and out of view on July 17. 

With their complex magnetic fields, sunspots are often the source of interesting solar activity: During its 13-day trip across the face of the Sun, the active region — dubbed AR12665 — put on a show for NASA’s Sun-watching satellites, producing several solar flares, a coronal mass ejection and a solar energetic particle event. Watch the video below to learn how NASA’s satellites tracked the sunspot over the course of these two weeks.

Such sunspots are a common occurrence on the Sun, but less frequent at the moment, as the Sun is moving steadily toward a period of lower solar activity called solar minimum — a regular occurrence during its approximately 11-year cycle. Scientists track such spots because they can help provide information about the Sun’s inner workings. Space weather centers, such as NOAA’s Space Weather Prediction Center, also monitor these spots to provide advance warning, if needed, of the radiation bursts being sent toward Earth, which can impact our satellites and radio communications.  

On July 9, a medium-sized flare burst from the sunspot, peaking at 11:18 a.m. EDT. Solar flares are explosions on the Sun that send energy, light and high-speed particles out into space — much like how earthquakes have a Richter scale to describe their strength, solar flares are also categorized according to their intensity. This flare was categorized as an M1. M-class flares are a tenth the size of the most intense flares, the X-class flares. The number provides more information about its strength: An M2 is twice as intense as an M1, an M3 is three times as intense and so on.

Read more at NASA/Goddard Space Flight Center

Image: A blended view of the sunspot in visible and extreme ultraviolet light reveals bright coils arcing over the active region -- particles spiraling along magnetic field lines. (Credit: NASA's Goddard Space Flight Center/SDO)