Sunspot data for 28 September 2021 of period 2021Q3: (PREV DAY - NEXT DAY)

Sun210928_1008UTC_sketch.jpgSun210928_1013UTC.jpg


Today we had some 70% cumuli topped with light stratus. Transparency was poor, seeing was reasonalble. I made the following observation: 
Observation date/time:   28 September 10:08 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 (351mm distance, 80mm diameter)
Reference:               Earth's rotation axis
Exposure (transparency): 0.380ms
Seeing (SSSMon):         4.0-4.5"

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Total number of sunspots:   6

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