Meghnad Saha, an astrophysicist, is known for giving the world the Thermal Ionisation Equation, also known as the ‘Saha Equation’.

But while much has been written about his work on selective spectroscopy, molecular dissociation and propagation of radio waves, little is known about his life and his roots.

Saha was born in undivided India’s Seoratali village in Dhaka district on 6 October 1893 to parents, Jagannath Saha and Bhubaneswari Devi.

While financial conditions had him and his siblings drop out of school early on, they did not deter Saha who showed a keen interest in academics.

His professional career began in 1916 when he joined Calcutta University’s department of Applied Mathematics as a lecturer.

A year later, Saha joined the physics department where he taught subjects like spectroscopy and thermodynamics.

While many of his research papers remained unpublished due to financial constraints, in 1919, he received the Premchand Roychand Scholarship for his dissertation on the ‘Harvard Classification of Stellar Spectra’.

The scholarship took him to Europe for two years and gave him opportunities to work in the labs of scientists like Alfred Fowler and Walter Nernst.

In 1920, Saha formulated the thermal ionisation theory and his thesis on ‘Origin of Lines in Stellar Spectra’ won him the Griffith Prize of Calcutta University.

After returning to India, Saha joined the University of Allahabad in 1923 and worked there for the next 15 years, going on to write his famous book, ‘A Treatise on Heat’.

In 1938, he returned to the University of Calcutta as a physics professor. Here, he took several initiatives to promote academics.

India’s first-ever nuclear physics syllabus for masters was designed by Saha in 1940 and he also built a cyclotron, a first in the country.

He also started the Indian Science News Association (1935) and the Institute of Nuclear Physics (1950).

On 6 February 1956, Saha died of a heart attack.

From being a young boy eager to excel in his studies to being one of the world’s most renowned scientists, Saha shaped the face of modern science in India.