Stellar atmospheric refraction measurement correction method based on collinearity of refraction surfaces

A method for measuring and correcting stellar atmospheric refraction based on collinear refraction surfaces;

• characterized in that it comprises the following steps:
• Step 1, based on a star identification method, obtaining a matching relationship between an observation star in the star sensor and a reference star in a reference star catalogue according to the position coordinates of the observation star on the imaging plane of the star sensor and the reference star catalogue;
• Step 2, according to the first star identification result and the observation time and the observation position, converting the direction vector of the reference star corresponding to the observation star in the star sensor from the reference star coordinate system into a geographic coordinate system before entering the atmosphere layer;
• ie, the East-North-Up coordinate system, to obtain the zenith distance-altitude and the azimuth angle before entering the atmosphere layer,
• Step 3, based on the stellar atmospheric refraction surface collinear principle According to the position coordinates of the observed star on the imaging plane of the star sensor and the azimuth angle of the stellar obtained in the second step before entering the atmosphere layer, the position coordinates of the top direction of the earth on the imaging surface of the star sensor are solved;
• Step 4, performing atmospheric refraction correction on the coordinates of all the observation stars in the star sensor on the imaging plane after the star is identified according to the position coordinates of the earth top direction obtained in the third step and the sky top distance before the stellar obtained in the second step enters the atmosphere layer, so as to obtain theoretical position coordinates of all observed stars on the imaging surface of the star sensor after the atmospheric refraction is removed;
• Step 5, according to the calculated theoretical position coordinates of all the observation stars on the imaging surface of the star sensor after the atmospheric refraction is removed in the fourth step, the matching relationship between the star and the reference star in the first step, and the direction vector of the reference star in the geographic coordinate system in the second step, the attitude of the star sensor in the geographic coordinate system is solved.