The Pandora Spectrometer Instrument: 10 Years of Evolution

In 2005, NASA initiated an effort at Goddard Space Flight Center (GFSC) to address the gap in validation measurements through the development of cost-effective, easy-to-deploy, ground-based spectrometer called Pandora. Over the last decade, the Pandora spectrometer system has evolved into an improved instrument with expanded capabilities. When the spectrometer and head assembly are carefully calibrated, Pandora provides high-quality spectrally resolved direct sun/lunar or sky scan radiance measurements in the UV and visible wavelengths. The Pandora radiance measurements combined with trace gas spectral fitting routines, and radiative transfer modeling provide real-time data of key air quality relevant pollutants, which can be compared to similar measurements from satellites. Significant improvements to hardware, calibration, operations, and maintenance have been made over the years that have led to the deployment of an increased number of Pandoras. Additional changes to quality assurance and quality control of data have led to more consistent filtering of datasets. Involvement in numerous field campaigns has provided new opportunities to test Pandora's abilities to make measurements on moving platforms. Recent developments in the material used to make Pandora components have led to an improvement of the HCHO data measured by Pandora. The results of these improvements and other advancements from the past ten years of Pandora measurements are also synthesized in this presentation.