thumbnail

Status of use of lunar irradiance for on-orbit calibration

By:
, ,
Edited by:
Barnes W.L.
DOI: 10.1117/12.453450

Links

Abstract

Routine observations of the Moon have been acquired by the Robotic Lunar Observatory (ROLO) for over four years. The ROLO instruments measure lunar radiance in 23 VNIR (Moon diameter ???500 pixels) and 9 SWIR (???250 pixels) passbands every month when the Moon is at phase angle less than 90 degrees. These are converted to exoatmospheric values at standard distances using an atmospheric extinction model based on observations of standard stars and a NIST-traceable absolute calibration source. Reduction of the stellar images also provides an independent pathway for absolute calibration. Comparison of stellar-based and lamp-based absolute calibrations of the lunar images currently shows unacceptably large differences. An analytic model of lunar irradiance as a function of phase angle and viewing geometry is derived from the calibrated lunar images. Residuals from models which fit hundreds of observations at each wavelength average less than 2%. Comparison with SeaWiFS observations over three years reveals a small quasi-periodic change in SeaWiFS responsivity that correlates with distance from the Sun for the first two years, then departs from this correlation.

Additional Publication Details

Publication type:
Conference Paper
Publication Subtype:
Conference Paper
Title:
Status of use of lunar irradiance for on-orbit calibration
DOI:
10.1117/12.453450
Volume
4483
Year Published:
2002
Language:
English
Larger Work Title:
Proceedings of SPIE - The International Society for Optical Engineering
First page:
165
Last page:
175
Number of Pages:
11
Conference Title:
Earth Observing Systems VI
Conference Location:
San Diego, CA
Conference Date:
1 August 2001 through 3 August 2001