Evidence for a solar system-size accretion disk around the massive protostar G192.16-3.82

Seven-millimeter continuum observations of a massive bipolar outflow source , (;G192.16-3.82, were made at a milli-arc-second. resolution with a; capab ility that Links the National Radio Astronomy Observatory's Very Large Arra y radio interferometer with the Very Long Baseline Array antenna, Located i n Pie Town, New Mexico. The observations provide evidence for a true accret ion disk that is about the size of our solar system and located around a ma ssive star. A model of the radio emission suggests the presence of a binary protostellar system, The primary protostar, G192 S1, at the center of the outflow, with a protostar mass of about 8 to 10 times the solar mass, is su rrounded by an accretion disk with a diameter of 130 astronomical units (AU ). The mass of the disk is on the order of the protostar mass. The outflow is poorly collimated with a full opening angle of about 40 degrees; there i s no indication of a more highly collimated jetlike component. The companio n source, G192 S2, is Located 80 AU north of the primary source.