Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Thursday, 15 May 2025

‹ 14.05.2025 2025 16.05.2025 ›

Photosphere sunspot drawing and RDS evaluation

15.05.2025 photosphere drawing

High-resolution scan (3230 px)

Time
07:30 UT
Observer
Süleyman FİŞEK
g
4
f
15
R
55
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · BXO – 6Group 1 · BXO – 6 Group 2 · CHI – 5Group 2 · CHI – 5 Group 3 · HA_ – 3Group 3 · HA_ – 3
RDS data file (.gzd) 
[Gözlem]
Tarih=15.05.2025
Saat=07:30
Gözlemci=Süleyman FİŞEK
KontrolEden=Ergün EGE
Durumaçısı=-20.81
Enlemaçısı=-2.64
Boylamaçısı=105.79
Boylamfark=2
GKalite=3
GDurum=K.T
Kuzeyaçısı=-0.7
Sırano=20245
AyRasatNo=11
RasatÖnceki=14.05.2025
RasatSonraki=16.05.2025

[Leke Grupları]
Grupsayısı=4:3:1
LekeSayısı=15:14:1
RölatifSayı=55:44:11
01=BXO 06 +08.475 +44.486 150.276 +0.000 0000 0 +10.183 +46.401 +06.767 +42.572 +08.475 +46.201 +08.475 +42.771
02=CHI 05 +14.185 -46.593 059.197 +0.000 0000 0 +15.682 -44.324 +12.687 -48.862 +14.185 -44.524 +14.185 -48.662
03=HA_ 03 +16.754 -52.726 053.640 -1.000 0000 0 +17.514 -51.289 +15.993 -54.163
04=HH_ 01 -09.712 +78.362 184.152 -1.000 0000 0 -08.870 +80.980 -10.553 +76.626
20250515.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 →

2025/20250515_sf · SF · 6 frames · 128.6 MB · 07:57:45–08:00:15 UT

07:59:45 UT · 30 ms 07:58:45 UT · 30 ms 07:57:45 UT · 30 ms 08:00:15 UT · 60 ms · over-exposed 07:58:15 UT · 60 ms · over-exposed 07:59:15 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.