Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Solar Images Friday, 21 February 2025

‹ 20.02.2025 2025 23.02.2025 ›

Photosphere sunspot drawing and RDS evaluation

21.02.2025 photosphere drawing

High-resolution scan (3230 px)

Time
07:30 UT
Observer
Ergün EGE
g
8
f
60
R
140
Seeing
3 / 5

Sunspot groups and observation details →

Sunspot groups (from the drawing)

Group 1 · HR_ – 2Group 1 · HR_ – 2 Group 2 · AX_ – 1Group 2 · AX_ – 1 Group 3 · AX_ – 1Group 3 · AX_ – 1 Group 4 · CAI – 12Group 4 · CAI – 12 Group 5 · HR_ – 1Group 5 · HR_ – 1 Group 6 · CSO – 2Group 6 · CSO – 2 Group 7 · FHI – 15Group 7 · FHI – 15 Group 8 · DSI – 26Group 8 · DSI – 26 Group 9Group 9
RDS data file (.gzd) 
[Gözlem]
Tarih=21.02.2025
Saat=07:30
Gözlemci=Ergün EGE
KontrolEden=Korhan YELKENCİ
Durumaçısı=-19.45
Enlemaçısı=-7.06
Boylamaçısı=120.81
Boylamfark=2
GKalite=3
GDurum=B.A
Kuzeyaçısı=-0.5
Sırano=20192
AyRasatNo=7
RasatÖnceki=20.02.2025
RasatSonraki=23.02.2025

[Leke Grupları]
Grupsayısı=8:5:3
LekeSayısı=60:17:43
RölatifSayı=140:67:73
01=HR_ 02 +15.300 +19.455 140.265 -1.000 0000 0 +16.653 +20.657 +13.407 +18.253
02=AX_ 01 +03.411 +09.737 130.547 +0.000 0000 0 +03.934 +10.121 +02.888 +09.353 +03.411 +09.621 +03.411 +09.853
03=AX_ 01 +05.694 +03.158 123.968 +0.000 0000 0 +06.104 +03.575 +05.284 +02.740 +05.694 +03.760 +05.694 +03.240
04=CAI 12 +16.768 -17.772 103.380 +0.000 0000 0 +19.428 -15.340 +14.108 -20.510 +16.768 -15.234 +16.768 -20.310
05=HR_ 01 +10.318 -72.785 048.250 -1.000 0000 0 +10.715 -71.739 +09.921 -73.832
06=CSO 02 -09.409 +65.654 186.464 +0.000 0000 0 -07.822 +68.521 -10.996 +62.788 -09.409 +68.321 -09.409 +62.988
07=FHI 15 -16.240 +03.973 124.783 06.120 0000 0 -13.456 +12.556 -18.592 -04.611 -15.792 +10.580 -17.172 -02.647
08=DSI 26 -13.434 -10.133 110.677 +0.000 0000 0 -10.878 -04.882 -15.990 -15.383 -13.434 -05.820 -13.434 -15.183
20250221.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 →

2025/20250221_ee · EE · 4 frames · 85.7 MB · 07:39:01–07:48:08 UT

07:42:53 UT · 50 ms 07:48:08 UT · 60 ms 07:40:42 UT · 40 ms 07:39:01 UT · 30 ms

Coronado H-α animations from frame sequences

No Coronado observation for this day.