Anomalous Variations of Daily Residual Fluctuations of Astronomical Time of the Astrolabe in the Yunnan Observatory during 2008~2009

We analyze the variation of the residual fluctuations of the astronomical time (after correction for terrestrial coordinate change) measured by a photoelectric astrolabe in the Yunnan Observatory during 2008~2009.We probe possible relationship between anomalies of such residuals and earthquakes,particularly, the Wenchuan Earthquake (M=8.0) in May 12 of 2008,the Panzhihua Earthquake (M=6.1) in Aug.30 of 2008,and Kunming Earthquake (M=4.3) in Dec.26 of 2008,which all occurred near the Yunnan Observatory.We also discuss some problems related to the study.