A quick capture during a clear mid summer night. An “advantage” of the light polution here: even so astronomical twilight isn’t reached, the sky brightness is for approx. 3 hours in the range of SQM 19.5 to 19.9. SQM 20.0 is the maximum I measured in my backyard in spring 2020 with the excellent “lock-down” skies.

Hopefully a break in the currently cloudy and rainy weather for some additional O3 und S2 data during the next days before the moon returns.

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