Calibration plan for the Thermal Infrared Sensor on the Landsat Data Continuity Mission

The Landsat Data Continuity Mission consists of a two-sensor platform with the Operational Land Imager and Thermal Infrared Sensor (TIRS). Much of the success of the Landsat program is the emphasis placed on knowledge of the calibrationof the sensors relying on a combination of laboratory, onboard, and vicarious calibrationmethods. Rigorous attention to NIST- traceabilityof the radiometric calibration, knowledge of out-of-band spectral response, and characterizing and minimizing stray lightshould provide sensors that meet the quality of Landsat heritage. Described here are the methods and facilities planned for the calibrationof TIRS which is a pushbroom sensor with two spectral bands (10.8 and 12 micrometer) and the spatial resolution 100 m with 185-km swath width. Testing takes place in a vacuum test chamber at NASA GSFC using a recently-developed calibrationsystem based on a 16-aperture black bodysource to simulate spatial and radiometric sources. A two-axis steering mirror moves the source across the TIRS field while filling the aperture. A flood source fills the full field without requiring movement of beam providing a means to evaluate detector-to-detector response effects. Spectral response of the sensor will be determined using a monochromator source coupled to the calibrationsystem. Knowledge of the source output will be through NIST- traceablethermometers integrated to the blackbody. The description of the calibrationsystem, calibrationmethodology, and the error budget for the calibrationsystem shows that the required 2% radiometric accuracy for scene temperatures between 260 and 330 K is well within the capabilities of the system.