Translator Disclaimer
21 August 2009 MODIS solar diffuser stability monitor: function and applications
Author Affiliations +
MODIS reflective solar bands (RSB) are calibrated on-orbit using a solar diffuser (SD) with its degradation tracked by an on-board solar diffuser stability monitor (SDSM). The SDSM has 9 detectors with wavelengths from 0.41 to 0.94μm. It is operated during each scheduled SD calibration event, making alternate observations of the Sun and the SD. Due to a design defect in the SDSM there are significant ripples in the Sun view responses. Because of this, an alternative approach was developed by normalizing SDSM detector responses to detector 9 at 0.94μm. It has been very effective since the responses of all SDSM detectors have the same ripples and SD degradation at detector 9 wavelength is extremely small. After many years of on-orbit operations, the accumulated degradation at detector 9 can have some impact on the RSB calibration quality. As a result, a new approach is developed and implemented to characterize the SD degradation directly. This approach reduces the ripples via a look-up table (LUT) constructed with data carefully selected from the existing SDSM observations made in a short period. In this paper, we provide an overview of different approaches applied over the years by the MODIS Characterization Support Team (MCST) to track the on-board SD degradation. Results of both Terra and Aqua MODIS SD degradation derived from different approaches are presented and evaluated. Lessons learned from MODIS SD on-orbit operation and recent improvements for the RSB calibration are also discussed.
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Hongda Chen and Xiaoxiong Xiong "MODIS solar diffuser stability monitor: function and applications", Proc. SPIE 7452, Earth Observing Systems XIV, 745218 (21 August 2009);


S-NPP VIIRS lunar observations
Proceedings of SPIE (September 26 2014)
Terra MODIS RSB on orbit calibration and performance four...
Proceedings of SPIE (November 04 2004)
Trending results of MODIS optics on-orbit degradation
Proceedings of SPIE (September 24 2002)

Back to Top