Backscatter ultraviolet instrument solar diffuser degradation

All but one of the backscatter UV (BUV) instruments have used solar reflective diffusers made of ground aluminum to maintain instrument calibration after launch. These diffusers have been sued throughout mission life-times, which range from less than 1 years to over 14 years. Means for monitoring diffuser reflectance include mechanisms on the instruments as well as methods to infer reflectance using earth radiance data. We compare changes in diffuser reflectance for the various instruments and find some common behavior as well as significant differences. Changes which appear to occur at different rates are actually quite similar when corrections are made for the amount and direction of incident solar irradiation. However, a class of instruments, the SBUV/2, has significantly lower degradation rates. We find, as have previous authors, that spacecraft self-contamination is the most likely cause of diffuser changes and observed differences. Observed changes suggest that contaminant layer thickness is the main reflectance degradation mechanism in the first few years of operation.

[1]  Lawrence E. Flynn,et al.  Algorithm for the estimation of vertical ozone profiles from the backscattered ultraviolet technique , 1996 .

[2]  Graham S. Arnold,et al.  Photochemical Spacecraft Self-Contamination: Laboratory Results and Systems Impacts , 1989 .

[3]  Matthew T. DeLand,et al.  Final Report on Nimbus-7 TOMS Version 7 Calibration , 1996 .

[4]  O. Manuel Uy,et al.  Quartz crystal microbalance (QCM) flight measurements of contamination on the MSX satellite , 1996, Optics & Photonics.

[5]  Glen Jaross,et al.  Design of the ADEOS/TOMS instrument for ozone-trend assessment , 1995, Remote Sensing.

[6]  David F. Hall.  Flight measurement of molecular contaminant deposition , 1994, Optics & Photonics.

[7]  Glen Jaross,et al.  Calibration and postlaunch performance of the Meteor 3/TOMS instrument , 1995 .

[8]  D. Hall,et al.  Photo-enhanced spacecraft contamination deposition , 1985 .

[9]  Donald F. Heath,et al.  Observations on Degradation of Ultraviolet Systems on Nimbus Spacecraft , 1974 .

[10]  Ziauddin Ahmad,et al.  A new self‐calibration method applied to TOMS and SBUV backscattered ultraviolet data to determine long‐term global ozone change , 1991 .

[11]  Donald F. Heath,et al.  Characterization of the Nimbus-7 SBUV radiometer for the long-term monitoring of stratospheric ozone , 1988 .

[12]  A. J. Fleig,et al.  Total Ozone Determination from the Backscattered Ultraviolet (BUV) Experiment , 1982 .

[13]  Matthew T. DeLand,et al.  Calibration of the NOAA 11 solar backscatter ultraviolet (SBUV/2) ozone data set from 1989 to 1993 using in‐flight calibration data and SSBUV , 1995 .

[14]  Ernest Hilsenrath,et al.  Effects of Space Shuttle flight on the reflectance characteristics of diffusers in the near-infrared, visible, and ultraviolet regions , 1994 .

[15]  Graham S. Arnold,et al.  Absolute rates of vacuum-ultraviolet photochemical deposition of organic films , 1989 .

[16]  Glen Jaross,et al.  Ice radiance method for backscatter UV instrument monitoring , 1993, Other Conferences.

[17]  Christopher G. Shaw.  Wavelength and coverage dependence of spacecraft contaminant photodeposition , 1996, Optics & Photonics.

[18]  Robert D. Hudson,et al.  Evaluation of the NOAA-11 solar backscatter ultraviolet radiometer, Mod 2 (SBUV/2): inflight calibration , 1991, Defense, Security, and Sensing.

[19]  Philip T. C. Chen,et al.  Verification of molecular contaminant and atomic oxygen modeling for the Environmental Verification Experiment for the Explorer Platform (EVEEP) , 1994, Optics & Photonics.