Sisir Kumar Mitra, Indian radio astronomer (Calcutta 24 October 1890 – Calcutta 13 August 1963)

ACHIEVEMENTS

First to obtain experimental evidence for E layer of the ionosphere (1930)

Located C and D layers of ionosphere in With P. Shyam. Absorbing layer of the ionosphere at low height. Nature 135:953-4, 1935

Determined that ions in the F ionosphere’s layer caused luminescence of the night sky

Explained Appleton ionization anomaly   

Published Upper Atmosphere, basic reference for researches in this area (1947)

Papers in Nature

With H. Rakshit. Refraction of light waves by electrons. Nature 123:796-9, 1929

With H. Rakshit, P. Shyam et al. Effect of solar eclipse on ionosphere. Nature 132:442-3, 1933

Origin of the E-layer of the ionosphere. Nature 142:914-5, 1938

Active nitrogen and N⁼₂ (X^’) ions. Nature 154:1212-3, 1944

Energy imparted by active nitrogen. Nature 155:831, 1944

Variations in the after-glow brightness of active nitrogen under varied experimental conditions. Nature 154:576-7, 1944

With M.R. Kundu. Thunderstorm and sporadic E ionisation of the ionosphere. Nature 174:798-9, 1954   

HONORS

Mitra crater in Moon