National Science Day is celebrated in India to mark the discovery of the Raman effect by physicist C.V. Raman. File

National Science Day is celebrated in India to mark the discovery of the Raman effect by physicist C.V. Raman on February 28 in 1928. India has been celebrating National Science Day since 1986 when the Government of India decided to commemorate the announcement of the discovery of the Raman Effect and to encourage the development of a scientific mindset in the country.

National Science Day is observed to promote the significance of science in everyday life and highlight the various activities, endeavours, and accomplishments in the scientific field for the betterment of humanity.

Who was C.V. Raman?

Chandrasekhara Venkata Raman, popularly known as C.V. Raman, was born in Tiruchirapalli, Tamil Nadu in 1888. In 1921, as a professor at the University of Calcutta he was sent as a delegate to the International Universities Congress in London. His journey back home however, is what changed his future.

On his 15-day return trip back home, while aboard the SS Narkunda, he was fascinated with the deep blue colour of the Mediterranean sea. He found that the sea looked blue for pretty much the same reason the sky looks blue — the water was causing blue light to scatter more than other colours in the light.

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In the years that followed, Raman became engrossed with the ‘scattering question’. He began conducting many experiments to observe how light behaved while it passed through different types of substances. His hard work eventually led him to the the discovery of what is now known as the Raman Effect, also known as the Raman scattering on February 28, 1928. He was knighted in 1929, and in 1930, and became the first Asian to win a Nobel Prize for Physics.

What is the Raman effect?

Raman effect refers to the inelastic scattering of light by matter, resulting in a shift in the frequency of the scattered light. In simpler words, it is a change in the wavelength of light that occurs when a light beam is deflected by molecules.

The Raman effect forms the basis for Raman spectroscopy, which is used by chemists and physicists to gain information about materials. Spectroscopy is the study of the interaction between matter and electromagnetic radiation.

The Raman Effect over the years has been used in many fields such as chemistry, biology, medicine. The police too use a device known as the Raman Scanner adopting this principle to find out if people are carrying any illegal substances.

What is the objective of National Science Day?

The basic objective of the observation of National Science Day is to spread the message of the importance of science and its application among the people. It is celebrated as one of the main science festivals in India every year with the following objectives:

• To widely spread a message about the significance of scientific applications in the daily lives of people.

• To display all the activities, efforts, and achievements in the field of science for the welfare of human beings

• To discuss all the issues and implement new technologies for the development of science

• To encourage the people as well as popularize science and technology.

What is the theme of National Science Day 2025?

The theme for National Science Day 2025 is “Empowering Indian Youth for Global Leadership in Science & Innovation for Viksit Bharat.” It emphasizes the role of young minds in driving India’s scientific and technological progress, aligning with the vision of Viksit Bharat 2047, which aims for a developed and self-reliant India.