Shadows are shortest at solar noon, which is the time when the sun reaches its highest point in the sky.

This happens:

* Around midday for most locations. However, the exact time of solar noon varies throughout the year and by location.

* When the sun is directly overhead at the Tropic of Cancer (around June 21st) or the Tropic of Capricorn (around December 21st).

Here's why shadows are shortest at solar noon:

* Angle of the sun: The sun is at its highest angle in the sky at solar noon. The higher the sun, the less of an angle the sun's rays hit the Earth, resulting in shorter shadows.

* Angle of the sun's rays: The sun's rays are most direct at solar noon, meaning they are hitting the Earth at a more perpendicular angle.

Let me know if you'd like to learn more about shadows!