We have sunspots in all sizes and shapes, ones with a more complex magnetic structure than an other. But how can you know wether a sunspot is a threat for major solar flares? To know the differences, the Mount Wilson observatory in Califoria made up rules so that every sunspot gets their magnetic classification.

Every day the sunspots are counted and from every spot the Space Weather Specialist gives them their magnetic classification and the spot classification. On our website you'll find an overview of all the sunspots together with their classification types. Below you'll get to know what these mean.

The different classifications

1. α – Alpha:
   A unipolar sunspotgroup.
2. β – Bèta:
   A sunspot group that has a positive and a negative polarity (or bipolar) with a simple devision between the polarities.
3. γ – Gamma:
   A complex region in witch the positive and negative polarities are so irregularly distributed that they can't be classified as a bipolar Sunspot group.
4. β-γ – Bèta-Gamma:
   A bipolar sunspot group but complex enough so that no line can be drawn between spots of opposite polarity.
5. δ – Delta:
   The umbrae of opposite polarity in a single penumbra.
6. β-δ – Bèta-Delta:
   A sunspot group with a general beta magnetic configuration but contains one (or more) delta sunspots.
7. β-γ-δ – Bèta-Gamma-Delta:
   A sunspot group with a beta-gamma magnetic configuration but contains one (or more) delta sunspots.
8. γ-δ – Gamma-Delta
   A sunspot group with a gamma magnetic configuration but contains one (or more) delta sunspots.

More than half of the visible sunspot groups are Alpha and Bèta classes, the bigger sunspots mostly get bèta, bèta-gamma or bèta-gamma-delta. It is known that delta sunspots can be very active and produce the most intense solar flares.

The delta classification

Let's digg a bit deeper into the magnetic delta class. This is the most interesting type of sunspot due to the high activity they can cause. With the following list you can determin weather a sunspot has a magnetic delta structure:

1. Delta groups are often very big and 90 percent of the sunspots have a reversed polarity with a high activity level, especialy when big solar flares erupt. These have mostly a complex, unusual or broken view of the numbra.
2. Delta groups form by the are formed by the aggregation of sunspots with opposite polarity of various dipoles, which are linked to shared magnetic field lines rather than direct magnetic lines. All spots are located in the penumbral region.
3. Delta spots often last longer than one rotation of the Sun than other sunspots. However, new delta spots can be formed within the same area.
4. Delta sunspot groups usually do not separate, but rather die together.
5. Active delta groups emit strong H-alpha emissions. Sometimes filaments can come out of the group.

A perfect example of a very complex sunspot group with a beta-gamma-delta magnetic classification witch caused a X2 class solar flare.

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