Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Sunday, 13 April 2025

‹ 11.04.2025 2025 14.04.2025 ›

Photosphere sunspot drawing and RDS evaluation

13.04.2025 photosphere drawing

High-resolution scan (3230 px)

Time
06:50 UT
Observer
Korhan YELKENCİ
g
6
f
55
R
115
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · CAI – 7Group 1 · CAI – 7 Group 2 · EKC – 20Group 2 · EKC – 20 Group 3 · CAI – 7Group 3 · CAI – 7 Group 4 · CAI – 17Group 4 · CAI – 17 Group 5 · AX_ – 1Group 5 · AX_ – 1 Group 6 · HS_ – 3Group 6 · HS_ – 3
RDS data file (.gzd) 
[Gözlem]
Tarih=13.04.2025
Saat=06:50
Gözlemci=Korhan YELKENCİ
KontrolEden=Süleyman FİŞEK
Durumaçısı=-26.09
Enlemaçısı=-5.75
Boylamaçısı=169.03
Boylamfark=3
GKalite=3
GDurum=K.T
Kuzeyaçısı=0.2
Sırano=20223
AyRasatNo=7
RasatÖnceki=11.04.2025
RasatSonraki=14.04.2025

[Leke Grupları]
Grupsayısı=6:4:2
LekeSayısı=55:51:4
RölatifSayı=115:91:24
01=CAI 07 +17.145 +67.953 236.433 08.971 0000 0 +17.966 +71.673 +16.325 +64.232 +17.517 +70.730 +16.525 +64.432
02=EKC 20 +08.850 +66.630 234.543 22.302 0000 0 +10.883 +72.666 +05.288 +59.460 +10.683 +72.466 +05.488 +59.660
03=CAI 07 +17.530 +04.142 172.622 21.449 0000 0 +18.108 +06.519 +15.999 +01.764 +17.908 +06.319 +16.199 +01.964
04=CAI 17 +06.181 -32.884 135.596 23.343 0000 0 +08.118 -28.640 +04.244 -37.127 +07.918 -28.840 +04.444 -36.927
05=AX_ 01 -17.533 +23.359 191.839 -1.000 0000 0 -17.533 +23.359 -17.533 +23.359
06=HS_ 03 -07.141 +10.962 179.442 +0.000 0000 0 -06.367 +11.838 -07.914 +10.850 -07.141 +10.956 -07.141 +10.968
20250413.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 →

2025/20250413_ky · KY · 21 frames · 337.5 MB · 08:23:33–08:34:07 UT

08:31:06 UT · 30 ms 08:27:36 UT · 30 ms 08:24:17 UT · 70 ms · over-exposed 08:29:36 UT · 70 ms · over-exposed 08:28:36 UT · 50 ms · over-exposed 08:32:06 UT · 50 ms · over-exposed 08:33:06 UT · 70 ms · over-exposed 08:23:33 UT · 30 ms · over-exposed 08:23:55 UT · 50 ms · over-exposed 08:33:37 UT · 70 ms 08:32:36 UT · 50 ms 08:31:36 UT · 30 ms 08:34:07 UT 08:30:06 UT · 70 ms 08:29:06 UT · 50 ms 08:28:06 UT · 30 ms 08:30:36 UT 08:24:28 UT · 70 ms 08:24:06 UT · 50 ms 08:23:44 UT · 30 ms 08:24:39 UT

Coronado H-α animations from frame sequences

No Coronado observation for this day.