Matthew Pothen Thekaekara (1914–1976) was an Indian scientist and author of books and papers relating to

spectrophotometry Spectrophotometry is a branch of electromagnetic spectroscopy concerned with the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. Spectrophotometry uses photometers, known as spec ...

and the

solar constant The solar constant (''GSC'') is a flux density measuring mean solar electromagnetic radiation (total solar irradiance) per unit area. It is measured on a surface perpendicular to the rays, one astronomical unit (au) from the Sun (roughly the ...

besides works on

theology Theology is the systematic study of the nature of the divine and, more broadly, of religious belief. It is taught as an academic discipline, typically in universities and seminaries. It occupies itself with the unique content of analyzing the ...

. He was instrumental in publishing some of the earliest AM0 spectra, which is a model spectrum of the sun in space. The historic 1973 Thekaekara spectrum was the basis for ASTM E490 (

American Society for Testing and Materials ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, an ...

Standard Solar Constant and Zero Air Mass Solar Spectral Irradiance Table) from 1974 to 2000, when it was replaced by the most recent AM0 upgrade, in ASTM E490-00. Recent publications such as a 2007 paper authored by fellow

Malayali The Malayali people () (also spelt Malayalee and also known by the demonym Keralite) are a Dravidian peoples, Dravidian ethnolinguistic group originating from the present-day state of Kerala in India, occupying its southwestern Malabar coast. ...

scientist P. Shahmugan made extensive reference to the Thekaekara spectrum. In 2008 a paper by authors from

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

Goddard Space Flight Center and UC Laboratory for Atmospheric and Space Physics also made extensive application of the Thekaekara spectrum. Image of Fr

Books

*''The solar constant and the solar spectrum measured from a research aircraft, edited by Matthew P. Thekaekara. Solar energy. Spectrum, Solar. Aeronautics in astronomy''. *''Thoughts twice dyed : reprinted from the series of "One minute meditation" / by Matthew P. Thekaekara, S.J'' *"The Extraterrestrial Solar Spectrum" A.J Drummond and M.P. Thekaekara, Eds. Institute of Environmental Sciences, Mount Prospect Illinois, 1973.

References

Sources

*http://rredc.nrel.gov/solar/spectra/am0/special.html#Thekaekara *http://rredc.nrel.gov/solar/spectra/am0/text/Thekaekara.txt {{DEFAULTSORT:Thekaekara, Matthew Pothen Scientists from Kerala Spectroscopists 1914 births 1976 deaths