Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Monthly Sunspot Classification and Coordinates

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December 2025 Monthly report →

Each group: class – number of spots (B, ΔL). NS: No sunspot.

DrawingDayRClassification and Coordinates
03 169 HS_ – 2 (5, 34.7E), DAI – 14 (22, 51.1E), CAI – 4 (7, 60.2E), BXI – 8 (-7, 34.9W), AX_ – 1 (-11, 31.0W), HS_ – 7 (-16, 12.2E), FHC – 40 (-15, 27.1E), DHC – 13 (-14, 45.6E)
04 160 HS_ – 1 (5, 23.7E), DSI – 5 (23, 39.6E), CSI – 6 (7, 49.5E), AX_ – 1 (-3, 61.8W), CSI – 8 (-8, 46.8W), CHI – 3 (-16, 00.4E), FHC – 41 (-14, 15.7E), EHC – 15 (-14, 33.5E)
05 141 HA_ – 2 (5, 09.7E), CSO – 7 (22, 26.3E), HS_ – 3 (7, 35.2E), HR_ – 1 (-4, 79.1W), CAO – 5 (-7, 60.9W), HS_ – 1 (-16, 13.0W), FKC – 34 (-15, 02.2E), DHI – 8 (-14, 19.9E)
06 196 CSO – 2 (5, 03.3W), DSC – 22 (22, 12.1E), HS_ – 1 (8, 21.6E), CHO – 2 (-7, 76.7W), HH_ – 1 (-16, 27.5W), FHC – 72 (-16, 11.9W), EHC – 26 (-14, 06.6E)
10 105 BXO – 4 (22, 40.7W), CSI – 9 (26, 26.6W), HS_ – 1 (-16, 82.0W), FSC – 12 (-15, 55.8W), HS_ – 1 (-16, 41.5W), AX_ – 1 (-26, 19.3E), CSI – 7 (-24, 28.4E)
11 95 AX_ – 3 (23, 49.9W), CHO – 5 (26, 39.7W), FKC – 12 (-15, 63.7W), BXI – 5 (-15, 18.0W), DSO – 6 (-25, 15.9E), DSI – 4 (-10, 18.6E)
12 73 CSO – 3 (26, 53.8W), EHC – 5 (-16, 81.3W), HS_ – 1 (-17, 68.6W), CSI – 7 (-25, 02.8E), BXO – 7 (-12, 04.4E)
15 78 AX_ – 1 (1, 15.2E), CSI – 5 (8, 26.4E), CSO – 2 (-25, 38.1W), DHI – 8 (-15, 36.9W), AX_ – 1 (-8, 33.1W), AX_ – 1 (0, 14.2W)
16 67 BXI – 3 (1, 31.5W), BXI – 6 (8, 11.3E), AX_ – 3 (3, 23.5E), HS_ – 1 (-25, 54.2W), DSI – 4 (-15, 52.7W)
17 69 CAI – 4 (2, 38.4W), BXO – 3 (6, 02.2E), BXO – 6 (3, 13.5E), DAI – 5 (-15, 62.1W), HS_ – 1 (-26, 61.8W)
18 61 CRI – 5 (3, 01.8W), AX_ – 1 (10, 09.4E), HS_ – 1 (18, 71.2E), DAO – 3 (-15, 77.9W), HS_ – 1 (-25, 76.1W)
19 59 AX_ – 1 (4, 66.8W), BXI – 3 (5, 19.1W), AX_ – 1 (14, 26.4E), HS_ – 1 (19, 56.2E), AX_ – 3 (-14, 25.4E)
29 114 DSI – 3 (12, 39.8W), DSC – 11 (24, 47.9E), DKC – 6 (-10, 67.5W), HS_ – 1 (-14, 31.5E), DSC – 8 (-8, 40.4E), AX_ – 3 (-15, 48.8E), AX_ – 1 (-16, 63.2E), AX_ – 1 (-25, 73.6E)
30 111 DSO – 2 (11, 53.0W), DSI – 8 (24, 33.3E), CAO – 4 (-10, 79.7W), AX_ – 2 (-14, 18.2E), DSC – 12 (-8, 26.9E), AX_ – 1 (-16, 35.7E), AX_ – 1 (-12, 44.9E), AX_ – 1 (-25, 60.2E)