Recent observational results of the nearest protostellar object Orion Source I

Tomoya Hirota  (NAOJ)

We have been studying the nearest high-mass protostellar object Orion Source I using VLBI and interferometers including VERA, e-MERLIN, JVLA, and ALMA. High resolution (<50 mas or 20 au at the distance of 400 pc) continuum images from 850 GHz to 5 GHz revealed an edge-on dust disk and possible signature of radio jet. The rotating disk traced by the vibrationally excited H2O lines shows the Keplerian rotation with the enclosed mass of about 15 Solar masses and it drives a rotating outflow traced by the H2O and SiO thermal/maser lines. Thus, Orion Source I is the ideal target to investigate a prototypical disk-outflow system in high-mass star-formation processes. We will review these recent observational results and future prospects.