Apparent Position Calculation of Celestial Body in the Solar System Used for the Celestial Attitude Determination

Celestial apparent position is the key data for celestial attitude determination. At present, the study of apparent position calculation mainly focuses on ground and ocean; development in space-based platform should take a further step. A conversion principle of apparent position in the spacecraft and various position correction formula is introduced in this thesis; based on the new astronomical reference frame, a model is established to calculate the apparent position of celestial bodies in the solar system, through which instantaneous geocentric virtual position and observer-fixed apparent position can be calculated. Compared with geocentric virtual position of astronomical almanac, the difference value of Jovian planet' right ascension can be controlled within 10ms and declination difference under 220mas; Compared with observer-fixed apparent position of satellite tool kit, the difference value of right ascension can be kept under 0.15s and the declination difference under 2". Experiments show that the model can correctly compute instantaneous apparent position of celestial body in the solar system and such precision meets the requirements of celestial attitude determination.