Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Monday, 20 October 2025

‹ 17.10.2025 2025 21.10.2025 ›

Photosphere sunspot drawing and RDS evaluation

20.10.2025 photosphere drawing

High-resolution scan (3230 px)

Time
07:05 UT
Observer
Süleyman FİŞEK
g
12
f
24
R
144
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · AX_ – 1Group 1 · AX_ – 1 Group 2 · HS_ – 3Group 2 · HS_ – 3 Group 3 · AX_ – 1Group 3 · AX_ – 1 Group 4 · AX_ – 1Group 4 · AX_ – 1 Group 5 · CHO – 2Group 5 · CHO – 2 Group 6 · AX_ – 1Group 6 · AX_ – 1 Group 7 · BXO – 5Group 7 · BXO – 5 Group 8 · HS_ – 2Group 8 · HS_ – 2 Group 9 · AX_ – 1Group 9 · AX_ – 1 Group 10 · DHO – 5Group 10 · DHO – 5 Group 11 · AX_ – 1Group 11 · AX_ – 1
RDS data file (.gzd) 
[Gözlem]
Tarih=20.10.2025
Saat=07:05
Gözlemci=Süleyman FİŞEK
KontrolEden=Korhan YELKENCİ
Durumaçısı=25.87
Enlemaçısı=5.46
Boylamaçısı=177.39
Boylamfark=3
GKalite=3
GDurum=G.T , H.S
Kuzeyaçısı=-0.6
Sırano=20368
AyRasatNo=11
RasatÖnceki=17.10.2025
RasatSonraki=21.10.2025

[Leke Grupları]
Grupsayısı=12:3:9
LekeSayısı=24:5:19
RölatifSayı=144:35:109
01=AX_ 01 +05.373 +80.766 258.156 +0.000 0000 0 +05.825 +82.407 +04.920 +79.125 +05.373 +81.907 +05.373 +79.625
02=HS_ 03 +09.915 -03.863 173.527 -1.000 0000 0 +10.965 -02.722 +08.865 -05.400
03=AX_ 01 +07.718 -78.439 098.951 -1.000 0000 0 +07.718 -78.439 +07.718 -78.439
04=AX_ 01 -14.188 +59.984 237.374 -1.000 0000 0 -14.188 +59.984 -14.188 +59.984
05=CHO 02 -12.141 +28.448 205.838 +0.000 0000 0 -09.702 +32.300 -14.580 +24.866 -12.141 +31.830 -12.141 +25.660
06=AX_ 01 -09.794 +01.322 178.712 -1.000 0000 0 -09.794 +01.322 -09.794 +01.322
07=BXO 05 -15.830 -21.756 155.634 +0.000 0000 0 -13.705 -22.641 -16.461 -20.872 +00.000 +00.000 +00.000 +00.000
08=HS_ 02 -08.142 -43.916 133.474 -1.000 0000 0 -07.116 -42.455 -09.167 -45.378
09=AX_ 01 -20.260 -45.535 131.855 +0.000 0000 0 -19.783 -45.170 -20.269 -46.540 -20.260 -45.350 -20.260 -45.720
10=DHO 05 -11.847 -47.000 130.390 26.140 0000 0 -10.770 -43.231 -13.618 -50.770 -12.560 -45.479 -10.910 -48.842
11=AX_ 01 -09.203 -56.266 121.124 -1.000 0000 0 -09.203 -56.266 -09.203 -56.266
12=HH_ 01 -05.704 -75.181 102.209 -1.000 0000 0 -05.360 -73.596 -06.371 -76.767
20251020.gzd

Chromosphere (H-α) FITS frames

H-α

The images are made automatically with a fixed, gentle rule: uneven illumination and most of the limb darkening are removed, and the brightness is shown on a linear scale (no sharpening); prominences get their own scale outside the limb. Frames are ordered by sharpness (seeing); frames without the Sun (darks, bias) come last. Method →

2025/20251020_sf · SF · 6 frames · 128.6 MB · 07:26:37–07:29:38 UT

07:26:37 UT · 30 ms 07:28:08 UT · 30 ms 07:29:08 UT · 30 ms 07:28:38 UT · 60 ms · over-exposed 07:29:38 UT · 60 ms · over-exposed 07:27:37 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.