Abstract

A Fourier Transform Spactrometer based at the Caltech Submillimeter Observatory on Mauna Kea, HI (4100 m. above sea level) has now been operational for several years. The broadband spectra acquired with this instrument are complementary to the very narrowband heterodyne spectra more typical of astronomical and atmospheric observations at such long wavelengths. Although less sensitive than heterodyne observations, the broadband FTS approach has allowed a number of unique observations to be acquired in fields as diverse as atmospheric spectroscopy, planetary spectroscopy, and observations of the interstellar medium. Given the broadband nature of the spectra, accurate calibration for atmospheric and beam coupling effects are possible, allowing high precision to be achieved in the measurements both of our atmosphere's longwave opacity, and of planetary continuum brightness temperatures.

© 2001 Optical Society of America