Chinese satellite obtains global gravity field data

China's Tianqin-1 satellite has acquired the global gravity field data during its in-orbit operation, according to Sun Yat-sen University in south China's Guangdong Province.

The satellite was launched in December 2019 to test the technologies of the space-based gravitational wave detection program "Tianqin." The program Tianqin, meaning "harp in the sky," was initiated by the university in 2015.

The gravity field data is of great significance to the national economy and people's livelihood as the relevant data can aid geodesic survey, geophysics, oil and gas exploration, and disaster prevention and mitigation.

The program Tianqin plans to form an equilateral triangle constellation with a side length of about 170,000 kilometers around 2035, consisting of three satellites in the orbit at an altitude of about 100,000 kilometers, to construct a space gravitational wave observatory.

In June and November 2019, the program Tianqin successfully obtained the echo signal of the lunar transmitter and detected the signals from five lunar reflectors respectively to ensure the precise placement of the three satellites at the centimeter level in the future.