Sunspot Groups with Largest Areas (1874-2014)

Sunspot Groups with Areas Exceeding 2500 MSH

MSH stands for millionths of solar hemisphere; 1000 MSH corresponds to 23.8 times the cross-sectional area of Earth.
The regions that re-appeared by the rotation (about one month period) of the Sun are regarded as an identical region, and its maximum area over the life of the region is used in the ranking of areas.

Data Sources

1874-1954Royal Greenwich Observatory (1955), Sunspot and Geomagnetic Storm-Data Derived from Greenwich Observations 1874-1954
The dates of maximum area were taken from ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_REGIONS/Greenwich/
1955-1976Kopecký and Kotrc , Bull. Astron. Inst. Czechosl. 25, 171, 1974
Kopecký, Bull. Astron. Inst. Czechosl. 33, 65, 1982
The dates of maximum area were taken from ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_REGIONS/Greenwich/
1977-2013Royal Observatory, Greenwich - USAF/NOAA Sunspot Data (NASA/MSFC)
2014ftp.swpc.noaa.gov/pub/warehouse/2014/WeeklyPDF/ (NOAA/SWPC)

In Order of Areas

  • In the 'Data' column, I means white-light images, D means sunspot drawings.
  • ■ means an image or a drawing of the region is available. If no data are found on the day of maximum area, data of a nearby date are provided. The date will show up when the cursor is on the mark.
    □ means no data are available.

Rank Date of
Maximum Area
Area
(MSH)
Region Name Note Data
I D
1
(
(
1947
1947
1947
4
3
2
8
12
10
6132
4554
2944
RGO
RGO
RGO
14886
14851
14813

) one rotation before
) two rotations before


2 1946275202RGO14417
3
(
1951
1951
5
4
19
19
4865
2553
RGO
RGO
16763
16745

) one rotation before

4 19467294720RGO14585
5
(
1926
1925
1
12
19
31
3716
2934
RGO
RGO
9861
9830

) one rotation before

6 19381213627RGO12673
7 19893173600NOAA5395
8 19172143590RGO7977 □ □
9 19387203379RGO12902
10 19371053340RGO12553
11 1905223339RGO5441 □ □
12 19377283303RGO12455
13 1968213202RGO21482
14 1917893178RGO8181 □ □
15
(
1982
1982
6
7
14
12
3100
2870
NOAA
NOAA
3776
3804

) one rotation after

16 19419213088RGO13937
17 1989933080NOAA5669
17 199011183080NOAA6368
19 1939963054RGO13394
20 18922103038RGO2421 □ □
21 193810123003RGO13024
22 190510192995RGO5682 □ □
23 19399132993RGO13405
24 19886292900NOAA5060
25 1940162860RGO13502
26 19502162856RGO16410
27 1959182805RGO19109
28 201410262750NOAA12192
29 1897182743RGO4497 □ □
30 19744162706RGO23491
31 19203232690RGO9143
32 1982262640NOAA3594
33 195911292622RGO19651
34 1893872621RGO3106 □ □
35 200310292610NOAA10486
36 19844262590NOAA4474
37 19289272587RGO10746
38 1905372572RGO5473 □ □
39 19072162555RGO6108 □ □
40 19913252530NOAA6555
41 194812262513RGO15831
42 18941052511RGO3731 □ □
42 197011172511RGO22605
44 19591242502RGO19140

Chronological Order

  • In the 'Data' column, I means white-light images, D means sunspot drawings.
  • ■ means an image or a drawing of the region is available. If no data are found on the day of maximum area, data of a nearby date are provided. The date will show up when the cursor is on the mark.
    □ means no data are available.

Rank Date of
Maximum Area
Area
(MSH)
Region Name Note Data
I D
20 18922103038RGO2421 □ □
34 1893872621RGO3106 □ □
42 18941052511RGO3731 □ □
29 1897182743RGO4497 □ □
11 1905223339RGO5441 □ □
38 1905372572RGO5473 □ □
22 190510192995RGO5682 □ □
39 19072162555RGO6108 □ □
8 19172143590RGO7977 □ □
14 1917893178RGO8181 □ □
31 19203232690RGO9143
(
5
1925
1926
12
1
31
19
2934
3716
RGO
RGO
9830
9861
) one rotation before

37 19289272587RGO10746
12 19377283303RGO12455
10 19371053340RGO12553
6 19381213627RGO12673
9 19387203379RGO12902
21 193810123003RGO13024
19 1939963054RGO13394
23 19399132993RGO13405
25 1940162860RGO13502
16 19419213088RGO13937
2 1946275202RGO14417
4 19467294720RGO14585
(
(
1
1947
1947

1947
2
3

4
10
12

8
2944
4554

6132
RGO
RGO

RGO
14813
14851

14886
) two rotations before
) one rotation before


41 194812262513RGO15831
26 19502162856RGO16410
(
3
1951
1951
4
5
19
19
2553
4865
RGO
RGO
16745
16763
) one rotation before
27 1959182805RGO19109
44 19591242502RGO19140
33 195911292622RGO19651
13 1968213202RGO21482
42 197011172511RGO22605
30 19744162706RGO23491
32 1982262640NOAA3594
15
(
1982
1982
6
7
14
12
3100
2870
NOAA
NOAA
3776
3804

) one rotation after

36 19844262590NOAA4474
24 19886292900NOAA5060
7 19893173600NOAA5395
17 1989933080NOAA5669
17 199011183080NOAA6368
40 19913252530NOAA6555
35 200310292610NOAA10486
28 201410262750NOAA12192