Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Sunday, 4 October 2026

‹ 03.10.2026 2026 05.10.2026 ›

Photosphere sunspot drawing and RDS evaluation

04.10.2026 photosphere drawing

High-resolution scan (3229 px)

Time
11:00 UT
Observer
Burçin TANIK
g
4
f
17
R
57
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · BXI – 9Group 1 · BXI – 9 Group 2 · BXI – 6Group 2 · BXI – 6 Group 3 · AX_ – 1Group 3 · AX_ – 1 Group 4 · HA_ – 1Group 4 · HA_ – 1
RDS data file (.gzd) 
[Gözlem]
Tarih=4.10.2026
Saat=11:00
Gözlemci=Burçin TANIK
KontrolEden=Emre YILMAN
Durumaçısı=26.13
Enlemaçısı=6.56
Boylamaçısı=248.75
Boylamfark=1
GKalite=3
GDurum=G.T
Kuzeyaçısı=-1.1
Sırano=20581
AyRasatNo=4
RasatÖnceki=03.10.2026
RasatSonraki=05.10.2026

[Leke Grupları]
Grupsayısı=4:2:2
LekeSayısı=17:15:2
RölatifSayı=57:35:22
01=BXI 09 +13.774 +25.428 274.178 19.415 0000 0 +15.460 +28.700 +12.502 +22.787 +13.257 +26.387 +14.156 +23.836
02=BXI 06 +20.870 -26.519 222.231 +0.000 0000 0 +21.456 -22.733 +18.718 -30.305 +20.870 -22.933 +20.870 -30.105
03=AX_ 01 -21.450 +69.283 318.330 -1.000 0000 0 -21.450 +69.283 -21.450 +69.283
04=HA_ 01 -10.548 -59.698 189.520 +0.000 0000 0 -09.588 -58.439 -11.508 -60.956 -10.548 -58.940 -10.548 -60.457
20261004.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 →

2026/20261004_btö · BTÖ · 4 frames · 85.7 MB · 11:30:20–11:35:06 UT

11:30:20 UT · 30 ms 11:35:06 UT · 20 ms 11:32:01 UT · 60 ms · over-exposed 11:33:28 UT · 70 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.