Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Wednesday, 28 May 2025

‹ 27.05.2025 2025 29.05.2025 ›

Photosphere sunspot drawing and RDS evaluation

28.05.2025 photosphere drawing

High-resolution scan (3216 px)

Time
09:45 UT
Observer
Olcay PLEVNE
g
8
f
25
R
105
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · HS_ – 1Group 1 · HS_ – 1 Group 2 · BXI – 4Group 2 · BXI – 4 Group 3 · HK_ – 4Group 3 · HK_ – 4 Group 4 · HS_ – 3Group 4 · HS_ – 3 Group 5 · HS_ – 1Group 5 · HS_ – 1 Group 6 · BXI – 4Group 6 · BXI – 4 Group 7 · AX_ – 1Group 7 · AX_ – 1
RDS data file (.gzd) 
[Gözlem]
Tarih=28.05.2025
Saat=09:45
Gözlemci=Olcay PLEVNE
KontrolEden=Burçin TANIK
Durumaçısı=-16.65
Enlemaçısı=-1.11
Boylamaçısı=292.58
Boylamfark=1
GKalite=3
GDurum=K.T
Kuzeyaçısı=0.0
Sırano=20256
AyRasatNo=22
RasatÖnceki=27.05.2025
RasatSonraki=29.05.2025

[Leke Grupları]
Grupsayısı=8:4:4
LekeSayısı=25:12:13
RölatifSayı=105:52:53
01=HS_ 01 +05.833 +12.131 304.711 -1.000 0000 0 +06.835 +12.944 +04.831 +11.318
02=BXI 04 +03.530 -35.544 257.360 +0.000 0000 0 +03.475 -32.611 +02.632 -38.477 +03.530 -33.111 +03.530 -37.977
03=HK_ 04 +08.473 -47.726 244.854 -1.000 0000 0 +11.122 -44.589 +05.824 -50.862
04=HS_ 03 +10.830 -55.860 237.494 -1.000 0000 0 +11.680 -53.808 +09.970 -56.364
05=HS_ 01 -13.919 +43.403 335.983 -1.000 0000 0 -12.864 +44.496 -14.975 +42.309
06=BXI 04 -20.847 +01.363 293.943 +0.000 0000 0 -20.147 +02.841 -21.548 -00.115 -20.847 +02.341 -20.847 +00.385
07=AX_ 01 -16.450 -07.676 284.904 -1.000 0000 0 -16.450 -07.676 -16.450 -07.676
08=CAI 07 -13.338 -37.842 254.738 +0.000 0000 0 -11.555 -34.122 -15.120 -41.561 -13.338 -34.322 -13.338 -41.361
20250528.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 →

2025/20250528_op · OP · 4 frames · 85.7 MB · 09:52:12–09:56:36 UT

09:52:12 UT · 30 ms 09:53:42 UT · 40 ms 09:56:36 UT · 50 ms 09:55:14 UT · 60 ms · over-exposed

Coronado H-α animations from frame sequences

No Coronado observation for this day.