Professor Hidetoshi Katori (IMAGE) University of Tokyo Caption Professor Hidetoshi Katori during a recent experiment in Tokyo to measure Earth's gravitation. © 2021 Hidetoshi Katori Credit © 2021 Hidetoshi Katori Usage Restrictions Credit © 2021 Hidetoshi Katori License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.