ICID 68 => SUN_REGULAR_BINNINGFOUR

Illumination:

  • Sun irradiance over the regular aluminium reflection diffuser.

Purpose:

  • Spatial zoom-in sun irradiance measurements over the regular aluminium reflection diffuser.
  • Monitoring of spectral and spatial diffuser features.

Location:

  • Near the north pole, first light measurements, then dark measurements.

Usage:

  • Launch and Early Operations Phase (LEOP). Not used after 7 October 2004 (orbit 1223).

Description:

Sun over regular aluminium reflection diffuser spatial zoom-in measurement. First, 77 light measurements are performed at changing elevation angles (roughly in the range +4.0 degrees to -4.0 degrees), then 77 dark measurements are performed. As a function of the day in the year (season) the azimuth angle on the diffuser changes. The dark (background) measurements of ICID 69 are eventually used to correct these light measurements in the 0-1 data processing.