Lima and Callao will experience a curious solar phenomenon this week: three “shadowless days” on October 23, 24 and 25, when the Sun will be almost directly above the city around midday.
The phenomenon, also known as the zenith passage of the Sun, happens when the Sun reaches a position of 90 degrees above the horizon. For a few moments, objects and people can appear to have almost no shadow because sunlight falls almost vertically on the ground.
In Lima and Callao, this will happen very close to noon, between 11:50 and 11:52 a.m. The exact time can vary slightly depending on the location.
For travelers visiting Lima, this is also a good reminder to take care of yourself during the strongest hours of the day. Even if the weather looks cloudy, UV radiation can still be strong, and during the shadowless moment the sunlight will hit the ground more directly. Sunscreen, a hat or cap, sunglasses and staying hydrated are good things to keep in mind when exploring the city.
So, if you are visiting Lima this weekend, don't forget your hat and sunscreen. And if the sky is clear around midday, take a look at the ground. You might notice that your shadow has almost disappeared!
Source: https://www.peruinforma.com/lima-y-callao-registraran-sus-dias-sin-sombra-este-23-24-y-25-de-octubre/