Atmospheric Refraction Delay Toward Millimeter‐Level Lunar Laser Ranging: Correcting the Temperature‐Induced Error With Real‐Time and Co‐Located Lidar Measurements

Abstract

AbstractNext‐generation lunar laser ranging (LLR) aims for mm‐level accuracy, significantly promoting the study of gravitational physics. However, atmospheric refraction delay causes an unacceptable ranging error that can be efficiently corrected by neither the atmospheric delay models nor ray‐tracing calculation. Here we report on an improved ray‐tracing method, in which temperature profiles measured by radiosonde are replaced by those measured by a pure rotational Raman lidar, to realize real‐time and co‐located delay correction. Using 9‐night lidar observations, temperature‐induced delays of ±15 mm can be corrected for laser ranging, which is the largest residual in the LLR error budget.