Role Of UV Stellar Intensity Measurements In Atmospheric Transmissions Modelling

An 18-in. Cassegrain telescope and UV imaging system is used to observe and record starlight in the wavelength range 3000-3700 A . Such observations provide a real-time sampling of the atmosphere, allowing an accurate study of remote UV sources of unknown intensity. The spatial dependence for the trans-mission of radiation through the atmosphere has been calculated using the LOWTRAN 6 computer code, and the results are compared to data from various UV-emitting stars. Variations in the atmosphere are seen to strongly depend on aerosol concentration which affects meteorological range. Ground-level photometer measurements of extinction coefficients are extrapolated to yield atmospheric visibility profiles for our observation point.