Sunspot data for 4 April 2021 of period 2021Q2: (PREV DAY - NEXT DAY)

Sun210404_1645UTC_sketch.jpgSun210404_1655UTC.jpg


At the end of a totally grey day the sky cleared a bit, just good enough to make the following observation under hazy conditions:
Observation date/time: 04 April 2021 @ 16:45 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 (340mm distance, 80mm diameter)
Reference:             Earth's rotation axis

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Number of groups:      1
Group 1:
    Number of sunspots:    1
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Total number of sunspots:  1

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