Здесь:
1)Ссылки на сайты, дающие самую свежую информацию о событиях на Солнце;
2)Ссылки на сайты, посвященные предсказанию солнечной активности;
3)Классификация солнечных пятен;
4)Классификации вспышек (по рентгену, оптике (Ha), радио);

1)Исторически первая - оптическая классификация (в линии H_a ). Класс вспышки определяется  яркостью вспышки и ее видимым  размером. "Сильными" считаются вспышки класса 2B-4B.
За вспышками в H_a следят различные обсерватории: Lermonth, Holloman, Ramey Air Base, Voroshilov etc. Все эти данные публикуются в бюллетене  SGD- Solar Geophysical Data (NOAA).
Optical flare classification
 

	Flare	area	Flare brilliance
Importance	Actual area in units of square degrees (sq deg)	Apparent area in millionths of solar disk(10-6 solar A)
S  (small)	A<2.0	A<200	F(faint),N(normal),B(bright)
1	2.1<A<5.1	200<A<500
2	5.2<A<12.4	500<A<1200
3	12.5<A<24.7	1200<A<2400
4	A>24.7	A>2400

2) Классификация по рентгену По этой классификации, самые мощные вспышки соответствуют классу Х (экстра). (Максимальный балл Х20 = 20·10^-4 Вт/м2 зарегистрирован во вспышке 16 августа 1989 года). При вспышках класса X, как правило, большое количество протонов долетает до нас (регистрируются на спутниках и на уровне Земли). Такие вспышки называются протонными вспышками.  При некоторых мощных вспышках можно заметить, как выбрасываемое вещество (плазменный шар) отлетает от Солнца. Такия явления называются корональными выбросами масс (CME- coronal mass ejection). В зависимости от положения вспышки относительно солнечного меридиана, вещество может попасть на Землю (геоэффективная вспышка), а может не попасть. Выброшенное вещество долетает до Земли примерно за два дня (в зависимости от скорости выброса может быть разница в несколько часов).
X-ray flare classification

  Rank of a FLARE based on its X-ray energy output.  Flares are classified by the order of magnitude of the peak burst intensity (I) measured at the earth in the 1 to 8 angstrom band as follows:

              Class          (in Watt/sq. Meter)
                B                          I < 10^-6 Watt/m²
                C         10^-6 <= I < 10^-5
                M        10^-5 <= I < 10^-4
                X                        I > 10^-4

Протонные вспышки можно отследить по данным спутников  BATSE и GOES . (В июне этого года Бэтси утопили в океане, остался только Гоез) . Данные с гоесов ( 9 метеорологических спутников NOAA) можно посмотреть здесь, чтобы определить, когда какие были вспышки за последние 3 года:

Radio emission storms
     Emissions of the sun in radio wavelengths from centimeters to dekameters, under both quiet   and disturbed conditions.

      Type I. A noise storm composed of many short, narrow-band bursts
               in the metric range (300 - 50 MHz).
     Type II. Narrow-band emission that begins in the meter range
               (300 MHz) and sweeps slowly (tens of minutes) toward deka-
               meter wavelengths (10 MHz).  Type II emissions occur in
               loose association with major FLAREs and are indicative of
               a shock wave moving through the solar atmosphere.
      Type III. Narrow-band bursts that sweep rapidly (seconds) from
                decimeter to dekameter wavelengths (500 - 0.5 MHz).  They
                often occur in groups and are an occasional feature of complex
                solar ACTIVE REGIONs.
      Type IV. A smooth continuum of broad-band bursts primarily in the
               meter range (300 - 30 MHz).  These bursts are associated with
              some major flare events beginning 10 to 20 minutes after the
             flare maximum, and can last for hours.

SEL solar activity reports:
http://www.sel.noaa.gov/Data/alldata.html
http://www.sel.noaa.gov/getftp.cgi?get=/latest/RSGA.txt
http://www.sel.noaa.gov/getftp.cgi?get=/latest/wwv.txt
http://www.sel.noaa.gov/getftp.cgi?get=/indices/events
http://www.sel.noaa.gov/Data/index.html
http://www.sel.noaa.gov/today.html
http://www.sel.noaa.gov/advisories/email_lists.html
http://www.sel.noaa.gov/rt_plots/xray_1m.cgi
http://www.sel.noaa.gov/rt_plots/satenv.cgi
http://www.sel.noaa.gov/rt_plots/pro_3d.cgi
http://www.sel.noaa.gov/rt_plots/xray_5m.cgi

there are some more links:
 ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_NUMBERS
 ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_FLARES/XRAY_FLARES/
 ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_FLARES/HALPHA_FLARES/
 ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_FLARES/INDEX/
http://umbra.nascom.nasa.gov/batse/batse_years.html
 http://www.oma.be/KSB-ORB/SIDC/index.html
http://www.sel.noaa.gov/solar_images/ImageIndex.cgi
more links:http://www.astro.oma.be/SIDC/html/previsollinks.html

Количество пятен может оцениваться только субъективно, конечно. В зависимости от разрешения инструмента, мы увидим разное число пятен, и надо решать, насколько мелкие пятна (еще есть поры) нужно считать,  и т.д. Поэтому смысл имеет строить кривые только по однородным рядам наблюдений, на одном инструменте. Так,  MWO ведет свой счет пятен, а более общепринятой классификацией  можно считать числа, публикуемые в SGD monthly bulletin (unfortunately it doesn't have an electronic version yet) by NOAA.

(Note: there are actually at least two "official" sunspot numbers reported. The International Sunspot Number is compiled by the Sunspot Index Data Center in Belgium. The NOAA sunspot number is compiled by the US National Oceanic and Atmospheric Administration.)

Sunspot classification
From Solar-Geophysical Data (SGD) Explanation of Data Report, July 1987, Number 515 (Supplement)  -- description of sunspot group table as it appears in the monthly SGD.

     Sunspot Groups -- This table presents the sunspot groups' evolution as they cross the Sun's disk.  The groups are sorted by date of passage through Central Meridian.  Daily reports from a number of stations are listed.  The first column contains the NOAA/USAF region number assigned by the NOAA Space Environment Services Center (SESC) and USAF.  When no number was assigned, the number of a group which passes through CMP at about the same time is used with a letter
appended.  Letters are added sequentially depending on the number of unassigned different groups.  The Mt.
Wilson sunspot region number is also included when the Mt. Wilson reports are available.
 

     The magnetic classifications are defined as follows:

     A = alpha    All the magnetic measures in the group are of the same polarity.

    AP = alpha*p  All the magnetic measures in the group are of the same polarity which is that corresponding to the preceding spots in  that hemisphere for that cycle.

    AF = alpha*f  All the magnetic measures in the group  are of the same polarity which is that corresponding to the following spots in  that hemisphere for that cycle.

    BP =  beta*p  A bipolar group in which the magnetic measures indicate that the preceding spots are dominant.

      B = beta    A bipolar group in which the magnetic measures indicate a balance between the  preceding and following spots.

    BF = beta*f   A bipolar group in which the magnetic measures indicate that the following  Q spots are dominant.

BG = beta*gamma   A group which has general characteristics but in which one or more spots  are out of place as far as the polarities are concerned.

      G = gamma   A group in which the polarities are  completely mixed.

Statements will be added to the above classification if the group is also of the "D = delta-configuration": spots of opposite polarity within 2 1/2 degrees of one another and in the same penumbra.

     The sunspot classification in the column marked "Spot Class" is represented by three consecutive uppercase letters.  It is the revised classification devised by P.S. McIntosh of NOAA.  It consists of a modified Zurich Brunner class, the type of largest
spot within the group, and the relative spot distribution or compactness of the group.  This classification is included in the USSPS code, IUWDS, Synoptic Codes for Solar and Geophysical Data, Third Revised Edition, p.  108, 1973.  A discussion of the rationale and interpretation of this classification is included in the McIntosh review paper on sunspot observations in
The Physics of Sunspots, Sacramento Peak National Observatory, 1981.  The definitions of the classification and an illustration of the types of sunspots follow.

     When possible, separate bipolar sets of spots are identified by measured magnetic polarities, by the positions of spots relative to lines of polarity reversal inferred from structures on H-alpha filtergrams, and by the record of birth and evolution
of spots.  If these observations are not available, the following definitions identify most unipolar and bipolar spot groups:  (see Figure in SGD 515 Supplement and definitions to follow)

     Unipolar Group:  A single spot or a single compact cluster of spots with the greatest distance between two spots of the cluster not exceeding three heliographic degrees.  In modified Zurich H-class groups, this distance is measured from
     the outer penumbral border of the largest spot to the center of the most distant spot in the group. Strong new spots which are clearly younger than the nearby h-type spot (see Penumbra:  Largest  Spot) are usually members of a new emerging bipo-
     lar group and should be called a separate group.

     Bipolar (Elongated) Group:  Two spots or a cluster of many spots extending roughly east-west  with the major axis exceeding a length of three  heliographic degrees.  An h-type major spot can have a diameter of three degrees, so a bipolar
     group with an h-type spot must exceed five degrees in length.

Modified Zurich Class (first upper case letter in Table)

     A   A unipolar group with no penumbra.  There is no upper limit to the length of Class B groups.

     B   A bipolar group with no penumbra.

     C   A bipolar group with penumbra on spots of one polarity, usually on spots at only one end of an elongated group.  Class C groups become compact class D when the penumbra exceeds five degrees in longitudinal extent.  There is no upper limit to the length of Class C groups.

     D   A bipolar group with penumbra on spots of both polarities, usually on spots at both ends of an elongated group.  The length does not exceed 10 degrees of heliographiclongitude.

     E   A bipolar group with penumbra on spots of both polarities and with a length between 10 and 15 heliographic degrees.

     F   A bipolar group with penumbra on spots of both polarities and with a length exceeding 15 heliographic degrees.

     H   A unipolar group with penumbra.  Attendent spots are less than three heliographic degrees from the penumbra of the main spot. The principal spots are nearly always the leader spots remaining from an old bipolar group.  Class H groups become compact Class D when the penumbra exceeds five degrees in longitudinal extent.

Note that Zurich classes G and J are missing in this revision.  Class G groups are included in the definition of classes E and F, and class J groups are included in class H.

Penumbra:  Largest Spot (second upper case letter in Table)

     "x"   No penumbra.  The width of the gray area  bordering spots must exceed three arc seconds in order to classify as penumbra.

     "r"   The penumbra is rudimentary.  It is usually incomplete, irregular in outline, as narrow as three arc seconds, brighter intensity than normal penumbra and has a mottled, or granular, fine structure.  Rudimentary penumbra represents the transition between photospheric granulation and filamentary penumbra.  Recognition of rudimentary penumbra will ordinarily require photographs or direct observation at the telescope.

     "s"   Symmetric, nearly circular penumbra with filamentary fine structure and a spot  diameter not exceeding 2 1/2 heliographic degrees.  The umbrae form a compact cluster near the center of the penumbra.  Also, elliptical penumbrae are symmetric about a single umbra.  Spots with symmetric penumbra  change very slowly.

     "a"   Asymmetric, or complex penumbra with filamentary fine structure and a spot diameter along a solar meridian not exceeding 2 1/2 heliographic degrees.  Asymmetric penumbra is irregular in outline or clearly elongated (not circular) with two or more umbrae scattered within it.  The example in the figure is transitional between "s" and "a". Asymmetric spots typically change form from day-to-day.

     "h"   A large symmetric penumbra with diameter greater than 2 1/2 heliographic degrees.  Other than size, it has characteristics the same as "s" penumbra.

     "k"   A large asymmetric penumbra with diameter greater than 2 1/2 heliographic degrees.Other than size, its characteristics are the same as "a" penumbra.  When the longitudinal extent of the penumbra exceeds five heliographic degrees, it is almost certain that both magnetic polarities are present within the penumbra and the classificationof the group becomes Dkc or Ekc or Fkc.

Sunspot Distribution (third upper case letter in  Table)

     "x"   Single spot.
     "o"   An open spot distribution.  The area between leading and following ends of the group is free of spots so that the group appears to divide clearly into two areas of opposite magnetic polarity.  An open distribution implies a relatively low magnetic field gradient across the line of polarity reversal.

     "i"   An intermediate spot distribution.  Some spots lie between the leading and following ends of the group, but none of them possesses penumbra.

     "c"   A compact spot distribution.  The area between the leading and following ends of the spot group is populated with many strong spots, with at least one interior spot possessing penumbra.  The extreme case of compact distribution has the entire spot group enveloped in one continuous penumbral area.  A compact spot distribution implies a relatively steep magnetic field gradientacross the line of polarity reversal.

Mount Wilson Magnetic Classifications

  Alpha.  Denotes a unipolar sunspot group.
  Beta.  A sunspot group having both positive and negative magnetic
         polarities, with a simple and distinct division between
         the polarities.
  Beta-Gamma.  A sunspot group that is bipolar but in which no
         continuous line can be drawn separating spots of opposite
         polarities.
  Delta.  A complex magnetic configuration of a solar sunspot
         group consisting of opposite polarity umbrae
         within the same penumbra.
  Gamma.  A complex active region in which
         the positive and negative polarities are so irregularly
         distributed as to prevent classification as a bipolar group.

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