The first day of summer is the summer solstice. The longest day of the year, we get the most daylight of the calendar year. The Sun reaches its most northern point in the sky at local noon. After today, the days start getting shorter. The word solstice is from the Latin solstitium, from sol (sun) and stitium (to stop), reflecting the fact that the Sun appears to stop at this time (and again at the winter solstice).
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