Meghnad Saha FRS (October 6, 1893 – February 16, 1956) was an Indian astrophysicist best known for his development of the Saha equation, used to describe chemical and physical conditions in stars.

Meghnad Saha's best-known work concerned the thermal ionisation of elements, and it led him to formulate what is known as the Saha equation. He also invented an instrument to measure the weight and pressure of solar rays. <More>

References: Wikipedia