AAS 93-101

IN-FLIGHT MEASUREMENT OF THE NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION (NOAA)-10 STATIC EARTH SENSOR ERROR*,

E. Harvie**, O. Filla** and D. Baker***

Abstract

Analysis performed in the GSFC Flight Dynamics Division (FDD) measures error in the static-Earth sensor onboard the National Oceanic and Atmospheric Administration (NOM)-10 spacecraft using flight data. Errors are computed as the difference between Earth sensor pitch and roll angle telemetry and reference pitch and roll attitude histories propagated by gyros. The flight data error determination illustrates the effect on horizon sensing of systematic variation in the Earth infrared (IR) horizon radiance with latitude and season, as well as the effect of anomalies in the global IR radiance. Results of the analysis provide a comparison between static Earth sensor flight performance and that of scanning Earth sensors studied previously in the GSFC/FDD. The results also provide a baseline for evaluating various models of the static Earth sensor. Representative days from the NOAA-10 mission indicate the extent of uniformity and consistency overtime of the global IR horizon. A unique aspect of the NOAA-10 analysis is the correlation of flight data errors with Independent radiometric measurements of stratospheric temperature. The determination of the NOM-10 static -Earth sensor error contributes to realistic performance expectations for missions to be equipped with similar sensors.
*   This work was supported by the National Aeronautics and Space 
    Administration (NASA)/Goddard Space Flight Center (GSFC), under
    contract NAS ~31500. This paper is declared a work of the U.S. 
    Government and is not subject to copyright protection in the United States.

**  Computer Sciences Corporation (CSC), 10110 Aerospace Road, Lanham-Seabrook. 
    Maryland 20706.

*** NASA Goddard Space Flight Center, Greenbelt, Maryland 20771.