3-Dimensional kinematics of water/SiO masers in Orion-KL

Results of multi-epoch VLBI observations toward water/SiO masers in Orion-KL are presented. We conducted high-resolution VLBI observations of water/SiO masers with VERA to probe the structure and the kinematics of the disk/outflow in Orion-KL. The VERA observations provide the positions and proper motions of masers features in Orion-KL with the highest accuracy ever observed. The results of water and SiO maser observations suggest that Source I is a massive YSO with an accretion disk and a collimated outflow.