In this study,an attitude estimation method for a Mars airplane is proposed.Infrared radiation from the atmosphere and the ground and visible light radiation from the sun were modeled as functions of attitude.The radiation models were provided to an attitude estimation algorithm,where the Euler angles and the uncertain parameters of the radiation model were optimized such that the error between the radiation sensor output and radiation model output is minimized.The method proposed was validated using the data acquired during high-altitude flight experiment on Earth,which was simulating flight on Mars.The estimated results were compared with the integration of the angular velocity sensor output,and the precision was evaluated and discussed.