Figure 2 (IMAGE) Science China Press Caption DPD of BJ-KM, BJ-UR, KM-UR three baselines observation data on Dec. 15. Credit ©Science China Press Usage Restrictions None License Licensed 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.