Troy wrote:

Can you explain what the butterfly sunspot pattern is?

Maunder's butterfly diagram is a plot the latitude and number of sunspots over a solar cycle. The latitude of sunspots change in a pattern over a half solar cycle. http://solarscience.msfc.nasa.gov/images/bfly.gif http://www.windows2universe.org/sun/activity/butterfly.html Across an 11 year half-cycle, sunspots start forming in bands at higher north south latitudes, typically between 30 to 40 degrees. Over time, the latitude of the bands and number of the sunspots decreases until sunspots peter out near the equator at the end of the cycle. To my limited understanding, the sunspot bands mark magnetic field lines, that at the start of the cycle run north south, repeatedly being stretched into toroidal rings around the solar disk, due to the differential rotation being higher latitudes and the solar equator. These magnetic lines stretch and distort, and, as a result, at times they stick up out of the chromosphere. That is where sunspots form. Near solar max, the field lines reach a tipping point, collapse and weaken. The polarity of the Sun's poles reverse and new sunspots form at the highest latitudes with an opposite polarity. Then the number of sunspots declines preferentially towards the equator, as the strongest remaining field lines dissipate at solar minimum. Here's a NASA timelapse magnetogram of the Sun between about 1981 to 2008 that shows how the sunspot bands evolve over several cycles: http://www.nasa.gov/multimedia/videogallery/index.html?media_id=11917887 Here's a calcium and magnetogram image for today from the Solar Dynamics Observatory satellite that better shows today's band pattern: http://umbra.nascom.nasa.gov/images/latest_aia_1600.gif http://umbra.nascom.nasa.gov/images/latest_hmi_mgram.gif That today's solar Ha images shows parallel lines of sunspots in the northern and southern hemisphere is a good sign that the Sun is finally beginning to really be active again, after an unusually long period of solar minimum quiet. Many of us have been waiting for the next solar cycle to take off, so we can put our Lunt and Coronado PSTs to good use, and today's bands seems to signal that the next cycle with increasing levels of sunspot and flare activity really is here. Clear Skies - Kurt