September Starts with Flare(s)

The Solar Dynamics Observatory satellite keeps continuous watch on the Sun. It’s spotted several flares so far this month. The X9.3 flare was the strongest flare yet during the current solar cycle, the roughly 11-year-cycle during which the Sun’s activity waxes and wanes. The current cycle began in December, 2008, and is now decreasing in intensity and heading toward a solar minimum.

Video Credit: NASA

The Sun Flips

This computer animation shows the the Sun’s magnetic fields from January, 1997 to December, 2013. Magenta lines show where the Sun’s overall field is negative (where the field has more electrons), and green lines show where it is positive. Gray lines represent areas of local magnetic variation.

The Sun’s overall magnetic polarity, flips roughly every 11 years—though sometimes it takes quite a bit longer—defining what’s known as the solar cycle. The visualization shows how, in 1997, the Sun showed a positive polarity on the top. Over the next 12 years, each set of lines is seen to creep toward the opposite pole. By the end of the movie, each set of lines are working their way back to show a positive polarity, completing a full 22 year solar cycle.

At the peak of each magnetic flip, the Sun goes through periods of increased solar activity showing more sunspots and having more eruptive events such as solar flares and coronal mass ejections.

[youtube http://www.youtube.com/watch?v=B4UtVo7-yJA]

Video Credit: NASA/GSFC