GOSAT-2 (Greenhouse gases Observing Satellite-2), whose nick name is "IBUKI-2", is a JAXA satellite dedicated to the observation of Greenhouse Gases joining and expanding GOSAT capabilities. It carries enhanced versions of the two mission instruments present on GOSAT, TANSO-FTS-2 (Thermal And Near infrared Sensor for carbon Observation-Fourier Transform Spectrometer-2) and TANSO-CAI-2 (Cloud and Aerosol Imager-2).
The missions objective of GOSAT-2 are:
TANSO-FTS-2 is the Fourier Transform spectrometer same as the FTS on GOSAT, with improved characteristic: 5 bands (instead of 4) with the spectral range of each band optimized based on the results of the utilization of GOSAT data, two bands for the TIR, the bands other than the TIR are divided into two polarizations (P and S), extension of band 3 to observe the Carbon Monoxide.
The Instant Field of View (IFOV) is 15.8mrad which is same as GOSAT, but the footprint size became smaller from 10.5km to 9.7km due to the lower altitude of GOSAT-2. The pointing angle in the along-track direction became larger from ±20 degrees to ±40 degrees to extend the sun glint observation area and it makes possible to select the observation points freely within the capabilities of the pointing mirror moving speed. The scan duration is fixed to 4 secs. FTS-2 has 16 steps of the gain to take advantage of the dynamic range corresponding to very different radiance. FTS-2 has the function to avoid the clouds in the scene obtained by an intelligent pointing mechanism.
TANSO-CAI-2 is the push-broom type imaging radiometer using linear array sensor and band pass filter same as TANSO-CAI. The LOS of CAI-2 is tilted ±20 degrees in the along track direction (on GOSAT LOS points to nadir direction); CAI-2 consists of five lens systems and each lens system has two FOVs of forward and backward viewing.
New three observation bands are added to CAI-2 in addition to the four observation bands of CAI; and three bands are available to observe in forward and backward viewings.
Mission Facts and Figures