Overview and pre-flight tests of TANSO-3 onboard GOSAT-GW

Global Observing SATellite for Greenhouse gases and Water cycle (GOSAT-GW) is a Japanese Earth observation satellite carrying two mission instruments, Total Anthropogenic and Natural emissions mapping SpectrOmeter-3 (TANSO-3) and Advanced Microwave Scanning Radiometer 3 (AMSR3). TANSO-3 is a grating type imaging spectrometer to observe CO2, CH4 and NO2 and has two observing modes; wide mode and focus mode. Compared with the Fourier Transform Spectrometer (FTS) method adopted in Greenhouse gases Observing SATellite (GOSAT) and GOSAT-2, TANSO-3 can observe a much larger number of locations in a wide area. This paper describes the design overview and pre-launch tests of TANSO-3.