China achieves first daylight laser ranging to Moon

Chinese scientists have achieved the world’s first successful satellite laser ranging between Earth and a lunar-orbiting satellite, Tiandu-1, under strong daylight conditions, overcoming significant solar background interference. This technological breakthrough allows for precise, continuous measurement of satellite distance in the Earth-Moon space at any time, no longer restricting observations to night periods. The experiment, coordinated by the Deep Space Exploration Laboratory (DSEL) and other Chinese research institutions, significantly expands the potential for deep-space navigation, positioning, and communication. The enhanced capability will directly support China’s plans for an advanced Earth-Moon relay and navigation network, including the Queqiao constellation, and future missions such as the International Lunar Research Station. Researchers describe the technical challenge as akin to targeting a single hair from over six miles away while tracking a fast-moving object, highlighting the advance in measurement accuracy. This achievement is set to boost China’s ambitions for lunar exploration and deep-space missions.