Explanation

Eratosthenes was the first person to calculate the Earth's radius in the 3rd century B.C.E.

He was a Greek astronomer who lived in Alexandria, Egypt.

Eratosthenes's calculation of the Earth's radius was 6,366 km, which is close to the modern value of 6,378 km.

Explanation

In the early 1950s, the first successful vaccine was created by US physician Jonas Salk.

Salk tested his experimental killed-virus vaccine on himself and his family in 1953

First used Salk vaccine in 1955 ( in activated)

while 

A live attenuated (weakened) oral polio vaccine developed by Dr. Albert Sabin and first used in 1961.

Israel launched a polio vaccine drive after 1988 in April 2022.

Explanation

World Wide Web (WWW)

World-Wide Web Worm (WWWW)

English scientist Tim Berners-Lee invented the World Wide Web in 1989.

WWW Birthplace CERN near Geneva, Switzerland.

The browser was released to the general public in August 1991.

Explanation

On March 18, 2025, NASA astronauts Nick Hague, Sunita (Suni) Williams, and Butch Wilmore, along with Roscosmos cosmonaut Aleksandr Gorbunov, safely splashed down near Tallahassee, Florida in a SpaceX Dragon spacecraft.

A unique sight during landing was a pod of dolphins circling the capsule, making the event memorable.

Explanation

The idea was introduced in the late 1940s by John von Neumann,

He proposed that a program be electronically stored in the binary format in a memory

Explanation

King Abdulaziz Al-Saud, founder/first king of Saudi.

Al-Saud: 1882

Al-Saud: 1953

Establishment of Saudi: 1932

Explanation

• Michael Faraday is known as the Father of Electricity.
• He discovered the laws of electromagnetism.
• He also built the first electric generator and first electric motor.

Person	Known as the Father of
Theophrastus	Botany
Galileo Galilei	Modern Physics
Alexander Graham Bell	Telephone
Michael Faraday	Electricity

Explanation

• The first general-purpose electronic digital computer was the ENIAC 
• ENIAC stands for Electronic Numerical Integrator and Computer
• Completion Year: Finished in 1945 and announced publicly in 1946.
• Creators: Designed and built by John Mauchly and J. Presper Eckert
• At the University of Pennsylvania.

Last updated by NA on 09-09-2026

Explanation

Russia has developed an mRNA vaccine for cancer patients.

The vaccine is expected to be released in 2025.

The vaccine will be free for eligible Russian cancer patients.

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Explanation

On July 20, 1969, Neil Armstrong became the first human to step on the moon.

He and Aldrin walked around for three hours.

Born: August 5, 1930, Wapakoneta, Ohio, United States

Died: August 25, 2012, Cincinnati, Ohio, United States