We are grateful to R. Newman, T. Quinn, C. Speake, J. E. Faller, J. H. Gundlach, H. J. Paik, Z. H. Lu, J. Luo and S. H. Fan for discussions and suggestions. We thank Q. T. Fan, Y. T. Zhang, B. P. Wang, X. D. Fan, M. Ke, L. Zhao, Y. Tu, J. Q. Guo, D. C. Chen, W. M. Wang, X. L. Wang, X. J. Luo, X. H. Fu, J. Tang and Y. B. Cheng for their early works on G measurement. We thank the National Institute of Metrology (NIM) of China for the calibration of some measuring instruments, source masses and the length gauges. This work is partly supported by the National Natural Science Foundation of China under grants number 91536223, 11722542, 11325523 and 11605295, the National Basic Research Program of China under grant number 2010CB832801 and the National Precise Gravity Measurement Facility.

Reviewer information

Nature thanks S. Schlamminger and the other anonymous reviewer(s) for their contribution to the peer review of this work.