Archive | October 2013

Updated Graphs

I have run the code again using a log plot for the histogram seen below:


There appears to be a change in gradient around the -650 and 650 points. I took these values as the new threshold for the umbra/penumbra.

This gives thresholds which look like this:


Plotting just the umbra i produced the following plots of Area Vs. Time and Flux Vs. Time



The values of flux obtained seem to be consistent with those in the literature (~10^22 Maxwells)

Area Vs. Time for active region 11861

Histogram of 11861 field of view


Plot of field of view with positive threshold of 100 and negative threshold -100


Plot of area vs. time for polarities in active region 11861


Active regions 11861, 11864 and 11865 in magnetogram and 171Å

Attached is a video of the magnetogram and 171Å data up until Oct 14. There appears to be a winding up of the new flux emergence in 11861 as the large area of negative polarity enlarges during the 11 Oct this rotation may correspond to the slowly rotating swirl which we observed on 3 consecutive days at the SST (image attached below). This winding up of the magnetic field along with the mixed polarities in the active region may have contributed to the numerous flares produced by the region over the observing time period.


Evolving region 11861

October 9


October 10


October 11




Flux Emergence

Latest HMI magnetogram data shows flux emergence in sunspot 11856 over the last few days as can be seen in the video below

1st Update

In order to get used to solarsoft and line of sight magenetograms, I picked out 6 past solar flares and created videos (best viewed in HD) of the evolving magnetic fields as the flares occurred.  I downloaded the data from and wrote an IDL proceedure to batch process the .fits files into jpegs, then finally ran the images together using Adobe Lightroom.

Flare 1 – X2.1 – 6/9/2011 @ 22:16 UT

– Flare visible at 22:16 as breif flashes of embedded opposing polarities

Flare 2 – X1.8 – 7/9/2011 @ 22:23 UT

which reconnects with positive region at 22:35 UT (12 mintues after flare..)

Flare 3 – X5.4 – 7/3/2011 @ 00:24 UT AND X1.3 @ 01:14 UT

Flare 4 – M5.6 – 2/7/2012 @ 10:52 UT

in vicinity of flare site (flare not visible in video)
-Emerging negative polarity at [-180, -350]

Flare 5 – X1.4 – 12/7/2012 @ 16:52 UT


– Negative polarity hook/spiral extends into centre of positive polarity spot on right
– Negative/netural polarity at centre of second positive spot
– Dip in positive polarity at 16:46, 6 mintues prior to flare

Flare 6 – M6.5 – 11/4/2013 @ 07:16 UT


– Very small quickly emerging and dissolving flows of negative polarity between two spots