Images 18.08.2025 · Istanbul University Observatory Solar Observations

Solar Images Monday, 18 August 2025

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Photosphere sunspot drawing and RDS evaluation

High-resolution scan (3231 px)

Time: 11:10 UT
Observer: Ergün EGE
g: 4
f: 7
R: 47
Seeing: 3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · AX_ – 1

Group 2 · CRO – 4

Group 3 · AX_ – 1

Group 4 · HR_ – 1

RDS data file (.gzd)

[Gözlem]
Tarih=18.08.2025
Saat=11:10
Gözlemci=Ergün EGE
KontrolEden=Olcay PLEVNE
Durumaçısı=17.19
Enlemaçısı=6.8
Boylamaçısı=286.84
Boylamfark=0
GKalite=3
GDurum=B.A , K.T
Kuzeyaçısı=-0.5
Sırano=20324
AyRasatNo=12
RasatÖnceki=14.08.2025
RasatSonraki=19.08.2025

[Leke Grupları]
Grupsayısı=4:1:3
LekeSayısı=7:1:6
RölatifSayı=47:11:36
01=AX_ 01 +07.213 -11.282 275.558 +0.000 0000 0 +07.600 -10.926 +06.827 -11.639 +07.213 -11.425 +07.213 -11.138
02=CRO 04 -03.460 +13.742 300.582 +0.000 0000 0 -01.548 +17.277 -04.544 +10.206 -03.460 +17.770 -03.460 +10.406
03=AX_ 01 -16.740 -28.618 258.222 +0.000 0000 0 -16.396 -28.310 -17.850 -28.926 -16.740 -28.810 -16.740 -28.426
04=HR_ 01 -08.346 -79.980 207.742 +0.000 0000 0 -07.715 -77.309 -08.977 -80.887 -08.346 -78.691 -08.346 -81.269

20250818.gzd

Chromosphere (H-α) FITS frames

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 →

2025/20250818 · · 3 frames · 64.3 MB · 11:15:39–11:19:50 UT

11:15:39 UT · 50 ms

11:19:50 UT · 70 ms · over-exposed

11:17:00 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.