September 22.
It is the Winter Solstice
The summer solstice occurs in the northern hemisphere when the sun is at the most acute angle above the horizon. It usually occurs on or about June 21.
The spring Equinox occurs on April 21 st. The fall Equinox is on September 21 st. The summer Solstice occurs on June 21 st and the winter Solstice occurs on December 21 st.
In the Northern Hemisphere the summer solstice will usually happen between June 20 and June 22. For the Southern Hemisphere it will occur between December 20 and December 23.
At the winter solstice
The spring Equinox occurs on April 21 st. The fall Equinox is on September 21 st. The summer Solstice occurs on June 21 st and the winter Solstice occurs on December 21 st.
the answer is 5/7
September 21
The summer solstice can occur on any of the 7 days of the week with equal likelihood. There are 5 weekdays (Monday to Friday) out of 7 days, so the probability that the summer solstice will occur on a weekday is 5/7 or approximately 0.714.
The solstices are the longest and shortest days of the year; there are always two every year. In the Northern Hemisphere, the summer solstice (longest day) is usually June 20 or 21 and the winter solstice (shortest day) is usually December 20 or 21. In the Southern Hemisphere, the summer solstice (longest day) is usually December 20 or 21 and the winter solstice (shortest day) is usually June 20 or 21.
Winter solstice will occur on or around December 21, when the sun is at its greatest distance from the celestial equator.
The time between sunrise and sunset is a little longer each day from the December solstice to the June solstice in the northern hemisphere and from the June solstice to the December solstice in the southern hemisphere.