Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Tuesday, 16 December 2025

‹ 15.12.2025 2025 17.12.2025 ›

Photosphere sunspot drawing and RDS evaluation

16.12.2025 photosphere drawing

High-resolution scan (3222 px)

Time
10:40 UT
Observer
Olcay PLEVNE
g
5
f
17
R
67
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · BXI – 3Group 1 · BXI – 3 Group 2 · BXI – 6Group 2 · BXI – 6 Group 3 · AX_ – 3Group 3 · AX_ – 3 Group 4 · HS_ – 1Group 4 · HS_ – 1 Group 5 · DSI – 4Group 5 · DSI – 4
RDS data file (.gzd) 
[Gözlem]
Tarih=16.12.2025
Saat=10:40
Gözlemci=Olcay PLEVNE
KontrolEden=Korhan YELKENCİ
Durumaçısı=9.45
Enlemaçısı=-1.08
Boylamaçısı=144.04
Boylamfark=1
GKalite=3
GDurum=K.T
Kuzeyaçısı=0.0
Sırano=20405
AyRasatNo=9
RasatÖnceki=15.12.2025
RasatSonraki=17.12.2025

[Leke Grupları]
Grupsayısı=5:3:2
LekeSayısı=17:12:5
RölatifSayı=67:42:25
01=BXI 03 +01.423 +31.493 175.533 +0.000 0000 0 +02.445 +33.160 +00.400 +29.827 +01.423 +32.960 +01.423 +30.270
02=BXI 06 +08.363 -11.271 132.769 +0.000 0000 0 +10.975 -08.527 +05.752 -14.140 +08.363 -08.727 +08.363 -13.814
03=AX_ 03 +02.814 -23.523 120.517 +0.000 0000 0 +03.872 -22.434 +01.755 -24.612 +00.000 +00.000 +00.000 +00.000
04=HS_ 01 -25.266 +54.209 198.249 +0.000 0000 0 -24.590 +55.989 -26.473 +52.428 -25.266 +55.489 -25.266 +52.929
05=DSI 04 -15.156 +52.743 196.783 +0.000 0000 0 -13.659 +58.523 -16.652 +46.963 -15.156 +58.323 -15.156 +47.163
20251216.gzd

Chromosphere (H-α) FITS frames

No chromosphere observation for this day.

Coronado H-α animations from frame sequences

No Coronado observation for this day.