Projects of Astrometric Mission in the Era of Post Hipparcos: Space Interfermetry Mission

The projects of astrometric satellites such as FAME、DIVA、JASMINE、SIM Lite、Gaia、OBSS、JMAPS are briefly described.Their development process of space interferometers from 1980 to now is indicated,especially the current status of SIM project, which is a program on study of astrophysics with astrometric method,is given,such as the science,the structure of instrument,observing mode,the milestone of techniques and so on. The construction of SIM Lite reference frame,including selection of grid stars and quasars such as distribution,magnitude etc.as well as the linkage between SIM reference frame and radio reference frame ICRF-2 is presented.The comparison between the observing mode of Gaia and SIM is made and the complement of Gaia and SIM on astrophysics and reference frame is pointed.Finally,the "eight-five" key project of Chinese academy of sciences on optical interferometry is reviewed and some suggestions on the future work of this project are given.