#zero shadow day

16th May 2024 at 12:35 PM was the zero shadow moment today.

GIF - observe the shadow of the grills becoming zero/ null/ nil at Zero Shadow Moment. Below are the individual photos of the GIF:

↑16-05-2024 at 11:14 am↑

↑16-05-2024 at 11:42 am↑

↑16-05-2024 at 12:06 pm↑

↑16-05-2024 at 12:17 pm↑

↑16-05-2024 at 12:24 pm↑

↑16-05-2024 at 12:35 pm ZERO SHADOW MOMENT↑

2018 - What not to do on Zero Shadow Day? Ans: A silly mistake.

16th May 2023, 12:35 pm was the Zero Shadow Moment.

I happened to see the clock at 12:30 pm and rushed out with a marker & kept it upright on a flat tile under the sun. Lo behold, the clouds came and blocked the Sun exactly at the moment of Zero shadow! At precise 12:35 pm, the clouds blocked the Sun and instead of direct sunlight, it was diffuse light that doesn/t cast a shadow. So now, I got zero shadow, but due to clouds. Lol. You can check my previous failure of recording the zero shadow day in the year 2018. The fault was in the bottle used in the experiment. This time, I didn't do the mistake of using the bottle, but the clouds played their game well.

↑ The diffuse light due to clouds blocking the Sun at exactly the Zero (0) shadow moment. ↑

↑ Clouds obscuring the Sun at Zero shadow moment ↑

↑ The Sun emerges behind the clouds after the Zero shadow moment at 12:36 pm. ↑

More about Zero Shadow Day (ZSD) here.

Zero Shadow Day, Bangalore

A zero shadow day is a day on which the Sun does not cast a shadow of an object at noon, when the sun will be exactly at the zenith position. It is a special celestial event that occurs twice a year. During this time, no silhouette appear of any object or living being when the sun is at its highest point in the sky.

For Kolkata, West Bengal - 1st Zero Shadow Day,2021: June 5 at 11:35 am 2nd Zero Shadow Day,2021: July 7 at 11:41 am

For Bhubaneshwar, Odisha - 1st Zero Shadow Day,2021: May 21 at 11:43 am - it continued for a brief period of about 3 minutes. 2nd Zero Shadow Day,2021: July 22 at 11:53 am

Article courtesy : Mr. Debiprosad Duari, Director - Research & Academic, M. P. Birla Institute of Fundamental Research, Kolkata https://www.mpbirlaplanetarium.org/m-p-birla-institute-of-fundamental-research/

What NOT TO DO on Zero Shadow Day?

Never ever use a pipe or a cylinder or a bottle that has projections protruding out from it’s outer surface wall.

Check the white bold arrow in the collage of time-stamped photos above and do not repeat this mistake next time.

The little protruding projection (i.e. - the thread of the bottle for the lid to screw upon), will cast a shadow and in spite of 0 shadow moment, you will have a shadow.

Ideal objects for observation are: cylindrical straight pipe without projections or protrusions.

I have captured the zero shadow moment with the shadow introduced because of my mistake or the artifact in the bottle’s edge! Click the photo to enlarge.

Click →  Zero Shadow Day to know more & don’t worry this phenomenon repeats twice every year for your location. So you always have another chance! 2023 Epic fail on Zero Shadow Day.

FRIEND: What is Zer0 shadow day?

ME: Keep an pen / pencil / water bottle / PIPE standing erect, exactly 90° on a flat surface preferably on white paper under the Sun. Usually they will cast a shadow. On zero shadow day, they will not cast a shadow.

FRIEND: How do I observe?

ME: First of all, never observe or look at the Sun directly or indirectly in any way and to observe the zero shadow day, you have look down at shadows around you or under your feet and NOT AT SUN. IT HAPPENS FOR LESS THAN A MINUTE.

FRIEND: Okay and?

ME: You will appreciate it if you start observing may be say 5 minutes before and after its onset. You will see the shadow disappear for a moment and then reappear. It is like an eclipse. If you see before and after, you see it better, as you can compare. But eclipse takes long time to start & finish. Here it will be in seconds.

FRIEND: Thank you.

ME: Check this video on YouTube of how to observe. It is for only 40 seconds!

FRIEND: Is there any APP to find zero shadow for my location?

ME: Yes. Zero Shadow Day on Android.

FRIEND: Wow :D

ME: CAUTION - Never look or observe the sun at all even for a brief moment with unaided eyes or through dark / protection glass of any kind.

My experiments to record the ZERO SHADOW DAY in 2018 (silly mistake) & 2023 (epic fail) ←