Sunday, June 20, 11:31 PM . . .

. . . is the exact moment in time when Earth's northern hemisphere achieves the maximum tilt toward the Sun on it's 365.25 day, 60,000 mph orbit around the Sun. This astronomical event is called the Summer Solstice; it is the first day of astronomical summer.

Meteorologists use a monthly system to record seasonal weather records. Meteorological Summer runs from June 1st to August 31st.

A maximum tilt toward the Sun produces:

- The highest Sun angle (shortest shadows)

- The most direct and intense/concentrated sunlight (Sun-bloc is a must!)

- The maximum hours/minutes of daylight (at a given latitude)

- The higher the latitude, the greater the duration of daylight

- Above the Arctic Circle in the far north, the Sun never sets!

Earth is a sphere with 50% of its surface always illuminated by sunlight and 50% in it's own shadow (what we call, night). It is interesting to note (and confusing too), that the tilt of our planet's rotational axis never changes as it always points in the same direction - but the tilt relative to incoming sunlight does change as we orbit the Sun. This change in relative tilt affects the amount of time that "window of illumination" is "open" and it produces variations in the strength of sunlight. This is very hard to visualize without a proper model; this Youtube video does a good job.

(1) Why Do We Have Different Seasons? | California Academy of Sciences - YouTube

The SUMMER SOLSTICE also marks the point at which the amount of daylight

decreases (about 2 minutes less per day) for the next 6 months. Most people begin to notice this change in late July or early August when they remark, "Hey, its starting to get dark early."

Fact is, it's been getting darker ever since the last week of June.

For the 30% of Earth's population that lives in the southern hemisphere, June 20 marks their

WINTER SOLSTICE as their bottom half of our planet is tilted away from the Sun, resulting in fewer daylight hours/minutes and much weaker, diffuse (spread out) sunlight.