Development of a portable integrating sphere source for the Earth Observing System's calibration validation programme

We have designed and built a portable integrating sphere source for use at the National Aeronautics and Space Administration (NASA) satellite sensor calibration facilities in support of the Earth Observing System (EOS) calibration programme. The source is designed to complement existing detector-based validation methodologies over the spectral range 400-2500 nm, affording extra flexibility in implementing the programme. Details of the design and operation of the portable source will be described and discussed.