Landsat 9 Thermal Infrared Sensor 2 On-Orbit Calibration and Initial Performance

Abstract

The Thermal Infrared Sensor 2 (TIRS-2) on Landsat 9 launched September 27, 2021 and underwent a variety of tests during its commissioning phase to establish its postlaunch performance. We report on the calibration updates performed to maintain its calibration and generate high quality imagery. This is done by transferring the SI-traceable pre-launch calibration to on-orbit while accounting for changes in the TIRS-2 response as detected through on-board calibrator observations. Additional empirical corrections were implemented to mitigate image striping observed on-orbit. The detector arrays were monitored through its commissioning phase to ensure that stable detectors were chosen for operations. TIRS-2 has demonstrated ~0.025% instability over its orbit, ~80 mK noise equivalent delta temperature, and an absolute radiometric uncertainty <1.4% in its nominal temperature range enabling a wide array of Earth science applications.