Sunspot data for 13 April 2021 of period 2021Q2: (PREV DAY - NEXT DAY)

Sun210413_0740UTC_sketch.jpgSun210413_0751UTC.jpg


yesterday I was too late back home to do any observations. This morning we had 40% cumuli, but otherwise good seeing, so I managed to make the following observation:
Observation date/time: 13 April 2021 @ 07:40 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:    4
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Total number of sunspots:  4

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