Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Wednesday, 21 May 2025

‹ 20.05.2025 2025 22.05.2025 ›

Photosphere sunspot drawing and RDS evaluation

21.05.2025 photosphere drawing

High-resolution scan (3230 px)

Time
08:00 UT
Observer
Süleyman FİŞEK
g
9
f
29
R
119
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · CHO – 4Group 1 · CHO – 4 Group 2 · AX_ – 4Group 2 · AX_ – 4 Group 3 · BXI – 6Group 3 · BXI – 6 Group 4 · AX_ – 3Group 4 · AX_ – 3 Group 5 · HH_ – 1Group 5 · HH_ – 1 Group 6 · CRI – 4Group 6 · CRI – 4 Group 7 · CSO – 4Group 7 · CSO – 4 Group 8 · HS_ – 1Group 8 · HS_ – 1
RDS data file (.gzd) 
[Gözlem]
Tarih=21.05.2025
Saat=08:00
Gözlemci=Süleyman FİŞEK
KontrolEden=Süleyman FİŞEK
Durumaçısı=-19.03
Enlemaçısı=-1.94
Boylamaçısı=26.15
Boylamfark=2
GKalite=3
GDurum=G.T
Kuzeyaçısı=-0.6
Sırano=20250
AyRasatNo=16
RasatÖnceki=20.05.2025
RasatSonraki=22.05.2025

[Leke Grupları]
Grupsayısı=9:5:4
LekeSayısı=29:18:11
RölatifSayı=119:68:51
01=CHO 04 +13.199 +31.849 057.999 +0.000 0000 0 +14.572 +34.708 +11.826 +28.991 +13.199 +34.508 +13.199 +29.191
02=AX_ 04 +17.281 +23.446 049.596 +0.000 0000 0 +18.116 +24.567 +16.446 +22.324 +00.000 +00.000 +00.000 +00.000
03=BXI 06 +16.579 +01.534 027.684 +0.000 0000 0 +18.719 +05.144 +14.439 -02.760 +16.579 +04.944 +16.579 -01.876
04=AX_ 03 +19.888 -57.615 328.535 +0.000 0000 0 +20.708 -56.624 +19.680 -58.606 +00.000 +00.000 +00.000 +00.000
05=HH_ 01 +06.600 -79.841 306.309 -1.000 0000 0 +06.676 -77.839 +05.444 -81.843
06=CRI 04 -06.206 +46.580 072.208 +0.000 0000 0 -05.104 +48.389 -07.308 +43.726 -06.206 +48.189 -06.206 +43.926
07=CSO 04 -12.296 -08.440 018.106 +0.000 0000 0 -11.515 -06.488 -13.770 -09.600 -12.296 -07.384 -12.296 -09.496
08=HS_ 01 -13.366 -48.955 337.195 -1.000 0000 0 -12.387 -47.742 -14.344 -50.169
09=CSO 02 -06.182 -61.176 324.974 +0.000 0000 0 -05.732 -57.470 -06.632 -64.883 -06.182 -57.969 -06.182 -64.382
20250521.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 →

2025/20250521_sf · SF · 8 frames · 171.4 MB · 08:09:05–08:14:12 UT

08:09:05 UT · 30 ms 08:11:41 UT · 30 ms 08:12:42 UT · 30 ms 08:13:42 UT · 30 ms 08:12:11 UT · 60 ms · over-exposed 08:10:05 UT · 60 ms · over-exposed 08:14:12 UT · 60 ms · over-exposed 08:13:12 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.