Explanation

World Health Day is observed on 7th April every year.

Theme 2025: Healthier beginnings, hopeful futures

Theme 2026: Together for health. Stand with science

Additional Information: 

World Health Organization (WHO) was founded on 7 April 1948.

WHO has its headquarters in Geneva, Switzerland. 

Explanation

• Australia shortest day: 21 June
• Asia shortest day: 21 December
• Australia longest day: 21 December
• Asia longest day: 21 June
• Caused by Earth’s axial tilt of 23.5°

Last verified on 04-04-2026

Explanation

• International Day of Action for Rivers: 14 March
• International Day of Action for Rivers Objective: to discuss the issues on river management, river pollution, river conservation
• Theme 2026: Protect Rivers, Protect People
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Explanation

• 22 December night is the longest night of the year.
• 21 June day  the longest day of the year.

Explanation

Explanation

• World Earth Day is annually observed on April 22.
• The first Earth Day was held on April 22, 1970.
• Theme 2021: Restore Our Earth
• Theme 2022: Invest In Our Planet
• Theme 2023: Investing in our planet

Explanation

If Earth had no atmosphere, the sky would appear black even during the day,

Hence, the sky would appear black, just like it does from space.

Explanation

"Equinox"  means Equal duration of day and night.

The time or date (twice each year) at which the sun crosses the celestial equator 

During the equinoxes, solar declination is 0°

The September equinox is called the autumnal or fall equinox on 23 September

The March equinox is called the vernal or spring equinox on 19 March or as late as 21 March

Explanation

Explanation

Days and nights are always of nearly equal length at the Equator,

The imaginary line circling the Earth at 0° latitude

This event is known as the equinox.

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