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LARES-2 satellite measures frame-dragging effect around the Earth.
Ignazio Ciufolini1, Antonio Paolozzi2, Erricos C Pavlis3
1Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology (APM), Chinese Academy of Sciences, Wuhan, China. ignazio.ciufolini@gmail.com.
Nature
|July 8, 2026
Summary
New satellite data precisely measures frame-dragging, confirming Einstein's theory of general relativity. This advancement offers an order-of-magnitude improvement in testing gravity and constrains alternative theories.
Area of Science:
- Geophysics
- Gravitational physics
- Astrophysics
Background:
- Laser-ranging offers precise tests of gravity in the weak-field regime.
- Frame-dragging, the spacetime distortion caused by rotating masses, is a key prediction of general relativity.
- Previous measurements of frame-dragging had significant uncertainties.
Purpose of the Study:
- To measure terrestrial frame-dragging with unprecedented precision.
- To provide stringent confirmation of Einstein's general theory of relativity.
- To constrain alternative gravitational theories and extensions.
Main Methods:
- Utilized data from the Laser Relativity Satellite 2 (LARES-2), LAGEOS, and GRACE satellites.
- Employed precise laser-ranging techniques to analyze satellite orbits.
- Combined data from multiple satellites for enhanced accuracy.
Main Results:
- Achieved a one-part-in-a-thousand relative uncertainty in the measurement of terrestrial frame-dragging.
- Demonstrated an order-of-magnitude improvement over previous Solar System determinations.
- Significantly constrained alternative gravitational models, including scalar-tensor extensions.
Conclusions:
- The results provide a stringent confirmation of general relativity in the near-Earth environment.
- The study places strong constraints on alternative theories of gravity that predict deviations in frame-dragging.
- The combined analysis also improved the determination of Earth's lunisolar tides, highlighting broader geophysical applications.
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