Cees BassaHappy new year! Another year means another year-long keogram! Every 15 seconds throughout 2022, my trusty all-sky camera took a picture of the sky above the Netherlands. Combining these 2.1 million images into a year-long keogram reveals this picture, which shows the length of the night change throughout the year (the hourglass shape), when the Moon was visible at night (diagonal bands), and the Sun higher in the sky during summer, as well as lots and lots of clouds passing overhead.
berndandeweg@cgbassa wow, what nice! You can see the not fully symmetrical shape nicely around 21 of june.
@berndandeweg Exactly, and again around December 20th, the winter solstice. This is due to the latest sunset and earliest sunrise occurring a few days before and after the summer solstice (and reversed for the winter solstice).