Which Indian astrophysicist formulated the Saha ionisation equation, which explains how the absorption lines in stellar spectra depend on temperature and pressure?

• A Subrahmanyan Chandrasekhar
• B Homi J. Bhabha
• C Vikram Sarabhai
• D Meghnad Saha ✓

Meghnad Saha (1893-1956) developed the Saha equation in 1920, a fundamental tool in astrophysics for classifying stars by their temperature and chemical composition.