Crescent shadows seen all over S'pore during solar eclipse, explained

Cool phenomenon.

Belmont Lay | December 27, 2019, 01:20 AM

The Boxing Day solar eclipse seen across Singapore left many on the island palpably excited -- including our prime minister:


While plenty of Singaporeans had their eyes aimed skyward, others observed some other peculiar sights as the Dec. 26 solar eclipse event was unfolding.

One phenomenon witnessed was the formation of crescent shadows.

Here's an example:

Banana-shaped light patterns

The repetitive banana-shaped light patterns cast on surfaces, such as floors and walls, are actually multiple images of the partly-eclipsed crescent of the sun.

This phenomenon is seen when light from the sun passes through the tiny gaps between the leaves of the trees.

The effect is the same as light passing through pinhole cameras -- except in this case, the pinhole is not necessarily very small.

Usually, as the sun is round, the light on the ground is just a dot of round light.

People usually don't think twice about the shape of the light shone on the ground or walls, and do not think of it as a projection of the image of the sun.

Here is what a solar eclipse image looks like versus a normal sun image on the same surface:


To reiterate: This phenomenon is captured as light from the sun passes through tiny openings, such as the gaps in between leaves on trees.

These gaps allow light rays from different parts of the partially obscured sun to create an enlarged image of the sun on the ground.

In fact, the same phenomenon occurs all the time, but the images created are circular, showing the entire solar disk.

Here are some more images of crescent shadows:




Top photo via Jane Lim & Sharon Kong via