Starquakes and the archaeology of stellar magnetism
Peer-Reviewed Publication
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Updates every hour. Last Updated: 6-Jun-2026 03:15 ET (6-Jun-2026 07:15 GMT/UTC)
As humanity's exploration of the Earth's internal structure deepens, Earth's free oscillations, serving as crucial "fingerprints" for revealing the large-scale structure and dynamic processes within the Earth, have always been a core subject in geophysics. Ground-based station observations are currently the mainstream method for measuring Earth's free oscillations. With the advancement of space technology, high-precision inter-satellite distance measurement holds the potential to become a novel method for detecting these oscillations.
In a recent paper published in Space: Science & Technology, a research team from the School of Physics and Astronomy at Sun Yat-sen University, in collaboration with the TianQin Research Center for Gravitational Physics, proposed a novel detection and analysis method for Earth's free oscillations utilizing the "TianQin" space-borne gravitational wave detector. The study constructed a theoretical response model for Earth's free oscillations within the TianQin detector and derived their analytical waveform for high-orbit satellite laser interferometric measurements. Through numerical simulation and Bayesian parameter estimation, the research team demonstrated that for a major seismic event like the 2008 Wenchuan earthquake, TianQin could achieve a clear detection with a signal-to-noise ratio as high as 73 and independently distinguish at least nine different free oscillation modes.
This research not only methodologically demonstrates for the first time the feasibility of directly detecting Earth's free oscillations using high-orbit gravitational wave detectors, but also pioneers a new interdisciplinary pathway integrating space-based gravity measurement with geophysical research. By leveraging the frequency splitting effect introduced by satellite orbital motion, this method can circumvent calibration errors inherent in traditional multi-station observations, enabling more independent and precise probing of Earth's internal structure. This work significantly expands the interdisciplinary application scope for China's autonomous space science mission—the TianQin project—and provides novel theoretical tools and technical reserves for future space-based exploration of Earth's internal structure and seismic mechanisms.