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Updated: Jun 21, 2026

Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Evidence for a solar system-size accretion disk around the massive protostar G192.16-3.82
D S Shepherd1, M J Claussen, S E Kurtz
1National Radio Astronomy Observatory, Post Office Box 0, Socorro, NM 87801, USA. dshepher@aoc.nrao.edu
Abstract:
Seven-millimeter continuum observations of a massive bipolar outflow source, G192.16-3.82, were made at a milli-arc-second resolution with a capability that links the National Radio Astronomy Observatory's Very Large Array radio interferometer with the Very Long Baseline Array antenna, located in Pie Town, New Mexico. The observations provide evidence for a true accretion disk that is about the size of our solar system and located around a massive 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 surrounded 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 is no indication of a more highly collimated jetlike component. The companion source, G192 S2, is located 80 AU north of the primary source.
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