A noon without a shadow: Hyderabad set to witness Zero Shadow Day on May 9

Hyderabad will witness Zero Shadow Day on Saturday at 12:12 pm, when shadows briefly disappear as the Sun reaches directly overhead. Birla Planetarium is hosting a free session to help people observe and understand this rare astronomical phenomenon.

Hyderabad: Imagine standing under the scorching midday sun and looking down to find that your shadow has completely vanished. Don’t panic, as it is not a glitch in the matrix or a scene straight from a sci-fi film. It is the unique astronomical event of Zero Shadow Day, set to take place in Hyderabad on Saturday.

For just a few minutes, at precisely 12:12 pm on Saturday, the city will experience ‘Zero Shadow Day’, the rare celestial phenomenon that occurs in the tropical regions when the Sun reaches its absolute zenith, positioned at a 90-degree angle directly above the Earth’s surface.

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Since the sunlight falls perfectly vertical, the shadow of any upright object, like a massive street lamp to a person standing upright, will appear as if it is retreating into itself, effectively making it disappear.

In addition to the visual spectacle, the ‘Zero Shadow Day’ also offers a window into the Earth’s complex geometry. Such a phenomenon occurs only between the Tropics of Cancer and Capricorn. Historically, the alignment of Zero Shadow Day allowed ancient astronomers to calculate the Earth’s circumference with surprising accuracy.

If you are interested in learning more and personally want to experience the phenomenon of Zero Shadow Day, then you’d better block your calendar on Saturday. The renowned Birla Planetarium in Hyderabad is hosting a special free public observation from 11.30 am to 12.30 pm on Saturday.

The session will offer a hands-on look at the mechanics of our solar system and science educators will be on-site to demonstrate the Earth’s tilt using ‘shadow tubes’ and interactive tracing experiments. Participants can bring simple household items like rulers or cylindrical containers to test the phenomenon themselves.

While the ‘shadow disappearing act’ only lasts for about two minutes, it is a reminder of Earth’s constant motion.

So, before heading out under the hot sun on Saturday to check out Zero Shadow Day, don’t forget to take some precautions from the dry scorching heat of Hyderabad.