Indian Scientist who gave colors to the stars – Meghnad Saha
There was a time when people wondered what stars actually are. As time passed they came to know that stars burned hydrogen to form heavier elements. One of the main scientists who added to our understanding of stars was Professor Meghnad Saha through his discovery of their chemical composition and physical characteristics.
He was born on 6th Oct 1893 in Bangladesh, the fifth child of Bhubaneswari Devi and Jagannath Saha. His parents did not want to educate their children due to extreme poverty. His father ran a small scale business and expected him to join the family business after finishing primary school.
Meghnad was keenly interested in studying further. A local doctor, Ananta Kumar, sponsored his education by giving him a job. He finished his schooling at the top of the class in Chemistry and Astronomy. He studied German, quantum physics and thermodynamics at the intermediate level. Later, he joined the Presidency College in Kolkata. There he met Mr.Satyendra Bose who was a prominent physicist. He received his B.Sc degree in 1913, majoring in Mathematics, and went on to finish his M.Sc in 1915.
As he came from a so-called low caste family he had to face a lot of difficulties and discrimination while at school and in college. Meghnad was among those who opposed the partition of Bengal when the then British government decided to split Bengal into two halves on religious lines.
In 1916, Meghnad was appointed Professor at the University College of Science, Kolkata. Initially, he was in the Department of Applied Mathematics but he and Satyendranath Bose (who was his classmate) moved to the Department of Physics to pursue their interest in the subject. Saha taught thermodynamics, hydrostatics, and spectroscopy. Though there was no research lab in the college he managed to continue his research while teaching.
During the freedom movement, Saha was quite impatient with Gandhiji’s path of non violent struggle. Saha and Gandhiji had many disagreements on the methods to be used. Gandhiji was not very well disposed towards science, whereas Saha believed that science could help eradicate poverty.
With persistent effort, Saha made a mark in the field of astronomy also. In 1917, he sent an essay on “Selective Radiation Pressure” to the Astrophysical Journal for publication. The journal expected him to pay some money to publish the full text of the essay. Due to lack of funds, he could not afford the price for publication. But the journal did publish a brief note about his essay.
In 1918, he got married to Radharani. The couple had 3 daughters and 3 sons.
Meghnad was awarded the highest degree of “Doctor of Science” by Kolkata University in 1919. In the same year, he published his thesis on ‘Harvard Classification of Stellar Spectra’, which won him the Premchand Roychand Scholarship. With this support he pursued his research for a period of 2 years in Europe. For a few months, he worked in London with Alfred Fowler and later relocated to Walter Nernst’s laboratory in Berlin.
He returned to India in 1923 and worked at the Allahabad University for 15 years. During this time, he was greatly appreciated for his work in astrophysics. He took the initiative of bringing in nuclear physics as a subject in M.Sc physics curriculum. He was the man behind the building of the first cyclotron in India.
Besides being an exceptional scientist he was also an accomplished administrator. He established the Indian Science News Association and Institute of Nuclear Physics. He was the person who prepared the Damodar Valley Project plan. He became a Member of the first Lok Sabha by winning the election from North-West Kolkata.
Every star has a spectrum, its light can be split into a series of dark and bright lines of different colours. The category of a star is determined by its spectrum As the spectral lines depend on temperature. Different temperatures give rise to different bands.
The spectral categorization of stars was explained by Saha’s thermal ionization equation. This equation explains the physical and chemical nature of the stars. It was helpful in determining the origin of stellar spectra. This was Saha’s pathbreaking contribution to the field of astrochemistry and astrophysics.
Professor Meghnad Saha passed away on 16 Feb,1956 due to cardiac arrest. The famous Astrophysicist Jayant Narlikar stated “Ionization equation is one of the great achievements of Indian sciences in the 20th century”. He believed Saha was worthy of the Nobel Prize, but in spite of being nominated many times, he missed the prize because the Nobel Committee opined that his work was not in the nature of a discovery.
Meghnad Saha is one of the most accomplished and acclaimed scientists of India.
Image Courtesy – wikipedia, anandabazar.com