Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Tuesday, 21 July 2026

‹ 20.07.2026 2026 22.07.2026 ›

Photosphere sunspot drawing and RDS evaluation

21.07.2026 photosphere drawing

High-resolution scan (3231 px)

Time
09:30 UT
Observer
Melike ERYILMAZ
g
4
f
30
R
70
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · DHC – 23Group 1 · DHC – 23 Group 2 · DKO – 4Group 2 · DKO – 4 Group 3 · HA_ – 2Group 3 · HA_ – 2 Group 4 · HH_ – 1Group 4 · HH_ – 1
RDS data file (.gzd) 
[Gözlem]
Tarih=21.07.2026
Saat=09:30
Gözlemci=Melike ERYILMAZ
KontrolEden=Burçin TANIK
Durumaçısı=6.39
Enlemaçısı=4.89
Boylamaçısı=160.48
Boylamfark=1
GKalite=3
GDurum=G.T , K.T
Kuzeyaçısı=-1.2
Sırano=20518
AyRasatNo=18
RasatÖnceki=20.07.2026
RasatSonraki=22.07.2026

[Leke Grupları]
Grupsayısı=4:2:2
LekeSayısı=30:27:3
RölatifSayı=70:47:23
01=DHC 23 +05.260 -04.868 155.612 +0.000 0000 0 +07.458 +00.647 +03.620 -10.383 +05.260 +00.447 +05.260 -10.183
02=DKO 04 +13.604 -54.878 105.602 +0.000 0000 0 +15.673 -51.949 +11.535 -57.806 +13.604 -52.149 +13.604 -57.606
03=HA_ 02 -05.624 +31.254 191.734 +0.000 0000 0 -04.141 +32.149 -07.108 +30.360 -05.624 +31.649 -05.624 +30.859
04=HH_ 01 -05.570 -73.626 086.854 +0.000 0000 0 -04.517 -71.335 -06.622 -75.916 -05.570 -71.836 -05.570 -75.416
20260721.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 →

2026/20260721_me · ME · 6 frames · 128.6 MB · 09:37:33–09:40:03 UT

09:39:03 UT · 30 ms 09:38:03 UT · 30 ms 09:40:03 UT · 30 ms 09:37:33 UT · 60 ms · over-exposed 09:38:33 UT · 60 ms · over-exposed 09:39:33 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.