Personal Details

• 🎂 Date of Birth
• 19 October 1910
• 📍 Place of Birth
• Lahore, Punjab, British India (now Punjab, Pakistan)
• 👨‍👩‍👧‍👦 Family
• Father: Chandrasekhara Subrahmanya Ayyar
• Mother: Sita Balakrishnan
• Siblings: Rajalakshmi, Balaparvathi, Vishwanathan, Balakrishnan, Ramanathan, Sarada, Vidya, Savitri, Sundari
• Spouse: Lalitha Doraiswamy
• Relatives: C. V. Raman (Uncle)
• 🎓 Education
• Subrahmanyan Chandrasekhar was homeschooled until the age of 12, with his father teaching him mathematics and physics, and his mother teaching him Tamil. He then attended Hindu High School in Triplicane, Madras, from 1922 to 1925. Afterward, he studied at Presidency College, Madras, where he earned a BSc (Honours) in Physics in 1930 and published his first paper in 1929.
• He was awarded a Government of India scholarship to pursue graduate studies at Trinity College, Cambridge, where he completed his MSc and PhD in 1933 under the guidance of R. H. Fowler, with a thesis on rotating self-gravitating polytropes. Chandrasekhar was subsequently elected to a Prize Fellowship at Trinity College for 1933–1937, becoming only the second Indian to receive this honor after Srinivasa Ramanujan.

Early Career

• Subrahmanyan Chandrasekhar embarked on his professional journey with an insatiable curiosity about the cosmos, quickly establishing himself as a prodigious talent in theoretical astrophysics.
• 💼 Early Beginnings
• In 1935, Chandrasekhar was invited by Harlow Shapley of the Harvard Observatory to be a visiting lecturer in theoretical astrophysics for three months. During this visit, he impressed Shapley but declined a Harvard research fellowship. At the same time, he met Gerard Kuiper, who recommended him for a faculty post at the Yerkes Observatory, University of Chicago. After some initial hesitation, Chandrasekhar accepted the position and joined Yerkes as an assistant professor of Theoretical Astrophysics in December 1936.

Career Journey

• 🏛️ University of Chicago and Faculty Positions
• Chandrasekhar remained at the University of Chicago for his entire career. He was promoted to associate professor in 1941 and full professor in 1943 at the age of 33. In 1946, when Princeton offered him a position with double the salary, the University of Chicago matched it to retain him.
• In 1952, he became the Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics and joined the Enrico Fermi Institute. In 1953, he and his wife became naturalized U.S. citizens.
• ⚔️ World War II Contributions
• During World War II, Chandrasekhar worked at the Ballistic Research Laboratory in Maryland, producing studies on shock waves and ballistics.
• He was invited to join the Manhattan Project, but security clearance delays prevented his participation.
• 🌟 Scientific Contributions and Philosophy
• Chandrasekhar followed a unique approach of systematization, focusing on one field for a decade, publishing multiple papers, and then summarizing his findings in a book. His research periods included:
• 1929–1939: Stellar structure and white dwarfs
• 1939–1943: Stellar dynamics and Brownian motion
• 1943–1950: Radiative transfer and quantum theory of hydrogen anion
• 1950–1961: Turbulence and hydrodynamic/hydromagnetic stability
• 1960s: Equilibrium and stability of ellipsoidal figures; general relativity
• 1971–1983: Mathematical theory of black holes
• Late 1980s: Theory of colliding gravitational waves
• 👨‍🏫 Work with Students
• Chandrasekhar mentored students for over 50 years, maintaining an average collaborator age of around 30. He required students to address him as "Prof. Chandrasekhar" until their PhD, after which they could call him "Chandra". He often traveled long distances to teach and trained students who later won Nobel Prizes.
• 📝 Editorial Work and Later Years
• From 1952 to 1971, he served as editor of The Astrophysical Journal, publishing important works like Eugene Parker’s solar wind paper. In his final years (1990–1995), he worked on Newton’s Principia for the Common Reader, translating Newton’s geometric methods into calculus-based explanations.
• 🌌 Legacy
• Chandrasekhar is best known for the Chandrasekhar limit, which defines the maximum mass of a white dwarf star at ~1.44 solar masses. This limit also indicates the minimum mass a star must exceed to collapse into a neutron star or black hole. He first calculated this limit in 1930 during his voyage from India to Cambridge for graduate studies.
• NASA named its third "Great Observatory," the Chandra X-ray Observatory, in his honor in 1979, and it was launched on 23 July 1999. The Chandrasekhar number in magnetohydrodynamics, asteroid 1958 Chandra, and the Himalayan Chandra Telescope are also named after him. R. J. Tayler described him as “a classical applied mathematician whose research was primarily applied in astronomy and whose like will probably never be seen again.”
• Chandrasekhar supervised 45 PhD students. His wife, Lalitha Chandrasekhar, donated his Nobel Prize money to establish the Subrahmanyan Chandrasekhar Memorial Fellowship at the University of Chicago, first awarded in 2000. The S. Chandrasekhar Prize of Plasma Physics, awarded by the Association of Asia Pacific Physical Societies, was instituted in 2014. The Chandra Astrophysics Institute (CAI) mentors high school students interested in astrophysics. Carl Sagan praised him as a source of “true mathematical elegance.” Google celebrated his 107th birthday with a Doodle in 28 countries on 19 October 2017.
• In 2010, the University of Chicago hosted the Chandrasekhar Centennial Symposium, attended by leading astrophysicists, with research talks later published in Fluid Flows to Black Holes: A Tribute to S. Chandrasekhar on His Birth Centenary (2011).
• 📚 Books
• Chandrasekhar authored several major works that have had a lasting impact on astrophysics and related fields. His notable books include An Introduction to the Study of Stellar Structure (1939/1958), Principles of Stellar Dynamics (1942/2005), Radiative Transfer (1950/1960), Plasma Physics (1960/1975), Hydrodynamic and Hydromagnetic Stability (1961/1981), Ellipsoidal Figures of Equilibrium (1969/1987), and The Mathematical Theory of Black Holes (1983/1998).
• He also wrote Eddington: The Most Distinguished Astrophysicist of His Time (1983), Truth and Beauty: Aesthetics and Motivations in Science (1987/1990), Newton's Principia for the Common Reader (1995), and The Theory of Turbulence: Subrahmanyan Chandrasekhar's 1954 Lectures (2011), showcasing his deep engagement with both theoretical and applied aspects of physics and astronomy.
• 📝 Journals and Papers
• He published around 380 papers during his lifetime, starting with his first paper on the Compton effect in 1928. His last paper, on non-radial oscillations of stars, was accepted in 1995. The University of Chicago Press published his selected papers in seven volumes covering stellar structure, radiative transfer, hydrodynamics, plasma physics, black holes, and general relativity.
• 📖 Books and Articles About Him
• Several authors have documented the life and work of Chandrasekhar. These include Empire of the Stars by Arthur I. Miller (2005), From White Dwarfs to Black Holes: The Legacy of S. Chandrasekhar edited by G. Srinivasan (1997), Chandra: A Biography of S. Chandrasekhar by Kameshwar C. Wali (1991), and S. Chandrasekhar: Man of Science edited by Radhika Ramnath (2012), highlighting his immense contributions to astrophysics and science.

Achievements and Milestones

• Here's a list of awards received by Subrahmanyan Chandrasekhar:
• 🏆 Awards and Recognition
• Nobel Prize, 1983
• Padma Vibhushan, 1968
• Bruce Medal, 1952
• Copley Medal, Royal Society, 1984
• Gold Medal, Royal Astronomical Society, 1953
• National Medal of Science, USA, 1966
• Henry Draper Medal, National Academy of Sciences, 1971
• Marian Smoluchowski Medal, 1973
• Henry Norris Russell Lectureship, 1949
• Gordon J. Laing Award, 1989
• Golden Plate Award, American Academy of Achievement, 1990
• Fellow of the Royal Society (FRS), 1944
• Member, American Philosophical Society, 1945
• Member, American Academy of Arts and Sciences, 1946
• Member, United States National Academy of Sciences, 1955
• Jansky Lectureship, National Radio Astronomy Observatory