“A reversal of the sun’s magnetic field is, literally, a big event,” said NASA’s Dr. Tony Phillips. “The domain of the sun’s magnetic influence (also known as the ‘heliosphere’) extends billions of kilometers beyond Pluto. Changes to the field’s polarity ripple all the way out to the Voyager probes, on the doorstep of interstellar space.”
To mark the event, NASA has released a visualization of the entire process [see below]. At the beginning, in 1997, the video shows the sun in Solar Cycle 23 with its positive polarity on the top (the green lines), and the negative polarity on the bottom (the purple lines). Each set of lines gradually move toward the opposite pole, showing a complete flip around 2002, completing the sun’s previous cycle. Both set of lines representing the opposing magnetic fields then begin to work their way back, to culminate in the latest flip.
“At the height of each magnetic flip, the sun goes through periods of more solar activity, during which there are more sunspots, and more eruptive events such as solar flares and coronal mass ejections,” said NASA’s Karen C. Fox. “Cosmic rays are also affected,” added Dr. Phillips. “These are high-energy particles accelerated to nearly light speed by supernova explosions and other violent events in the galaxy.” –Independent UK
The entire sun's magnetic polarity, flips approximately every 11 years -- though sometimes it takes quite a bit longer -- and defines what's known as the solar cycle. The visualization shows how in 1997, the sun shows the positive polarity on the top, and the negative polarity on the bottom. Over the next 12 years, each set of lines is seen to creep toward the opposite pole eventually showing a complete flip. By the end of the movie, each set of lines are working their way back to show a positive polarity on the top to complete the full 22 year magnetic solar cycle.
At the height of each magnetic flip, the sun goes through periods of more solar activity, during which there are more sunspots, and more eruptive events such as solar flares and coronal mass ejections, or CMEs. The point in time with the most sunspots is called solar maximum.
Credit: NASA/GSFC/PFSS
This video is public domain and can be downloaded at: http://svs.gsfc.nasa.gov/goto?11429