Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Tuesday, 4 August 2026

‹ 03.08.2026 2026 05.08.2026 ›

Photosphere sunspot drawing and RDS evaluation

04.08.2026 photosphere drawing

High-resolution scan (3229 px)

Time
08:40 UT
Observer
Tuğba BOZTEPE
g
6
f
48
R
108
Seeing
4 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · BXO – 1Group 1 · BXO – 1 Group 2 · CRI – 9Group 2 · CRI – 9 Group 3 · AX_ – 1Group 3 · AX_ – 1 Group 4 · EKI – 20Group 4 · EKI – 20 Group 5 · CSI – 3Group 5 · CSI – 3 Group 6 · CSI – 14Group 6 · CSI – 14
RDS data file (.gzd) 
[Gözlem]
Tarih=4.08.2026
Saat=08:40
Gözlemci=Tuğba BOZTEPE
KontrolEden=Emre YILMAN
Durumaçısı=12.1
Enlemaçısı=6
Boylamaçısı=335.76
Boylamfark=2
GKalite=4
GDurum=G.T
Kuzeyaçısı=-0.3
Sırano=20531
AyRasatNo=4
RasatÖnceki=03.08.2026
RasatSonraki=05.08.2026

[Leke Grupları]
Grupsayısı=6:4:2
LekeSayısı=48:31:17
RölatifSayı=108:71:37
01=BXO 01 +04.591 +81.271 057.310 +0.000 0000 0 +05.753 +83.385 +03.430 +79.157 +04.591 +83.185 +04.591 +79.357
02=CRI 09 +04.916 +55.215 030.975 +0.000 0000 0 +05.820 +59.472 +04.130 +50.958 +04.916 +59.272 +04.916 +51.158
03=AX_ 01 +24.986 +22.806 358.566 -1.000 0000 0 +24.986 +22.806 +24.986 +22.806
04=EKI 20 +16.527 +16.777 352.537 +0.000 0000 0 +20.469 +21.430 +12.585 +12.124 +16.527 +21.230 +16.527 +12.324
05=CSI 03 -05.626 +58.980 033.858 +0.000 0000 0 -04.517 +61.574 -06.734 +54.621 -05.626 +61.374 -05.626 +54.821
06=CSI 14 -05.518 +14.896 350.656 +0.000 0000 0 -04.463 +18.262 -06.573 +11.530 -05.518 +18.620 -05.518 +11.730
20260804.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 →

2026/20260804_tb · TB · 6 frames · 128.6 MB · 08:54:01–08:57:01 UT

08:57:01 UT · 30 ms 08:55:01 UT · 30 ms 08:56:01 UT · 30 ms 08:55:31 UT · 60 ms · over-exposed 08:56:31 UT · 60 ms · over-exposed 08:54:01 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.