Sunspot data for 21 December 2025 of period 2025Q4: (PREV DAY - NEXT DAY)

Sun251221_1235UTC_sketch.jpgSun251221_1237UTC.jpg





Click here for the sharpened image.
today started out grey, but around noon some clear spells arrived. Transparency was poor, but the scintillation monitor reported reasonable seeing on average. I made the following observation: 
Observation date/time:   21 December 2025 12:35 UTC
Telescope:               GTT60 (Galileo Type Telescope)
Focal length:            1490mm (plano convex singlet)
Aperture:                60mm
Stop:                    30mm
Eyepiece:                -75mm (plano concave singlet, 24mm aperture)
Observation type:        projection (338mm distance, 80mm diameter)
Reference:               Earth's rotation axis
Exposure (transparency): 1.230ms (using 82nm bandwidth green filter)
Seeing (SSSMon):         1.8-2.5" (1.1" at best)

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Total number of sunspots:  11

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