HEAT: Image and database browser for the thermal imager on Hayabusa2

Hayabusa2 is a sample return mission to asteroid 162173 Ryugu, which will arrive in 2018. The Thermal Infrared Imager (TIR) is onboard the spacecraft and will be used to make thermal observations to ensure a safe touch down and sample return, and to study the nature of the asteroid. This study developed a TIR database and data browser. Our developments are called Hayabusa2 Exploration Assistant for TIR (HEAT). HEAT has three uses: visualization, calibration, and analysis. It covers all of the uses based on functions, browsers, the database, and a data processor. This study considers two ways to perform calibrations: regression and direct conversion, which is interpolation with all of the ground test data. The TIR data analysis involves the following. First, TIR images are collected. Then, the local time is obtained for a specified longitudinal zone of the shape model. A TIR image includes surface temperature information. Third, the temporal profile of surface temperature is combined with individual TIR images and the local time. Fourth, the thermal inertia of the local site is estimated from the profile. Fifth, the thermal inertia is mapped. Finally, the thermal model is established by integrating the thermal inertia.