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Updated: Jun 21, 2026
11:34
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
Science (New York, N.Y.)
|May 26, 2001
Summary
Astronomers found a solar-system-sized accretion disk around a massive protostar, G192 S1, suggesting a binary protostellar system. This discovery offers new insights into massive star formation and evolution.
Area of Science:
- Radio Astronomy
- Astrophysics
- Star Formation
Background:
- Massive stars are crucial for galactic evolution.
- Understanding their formation is key to astrophysics.
- Observational constraints on massive protostars are limited.
Purpose of the Study:
- To investigate the structure of the massive bipolar outflow source G192.16-3.82.
- To search for evidence of an accretion disk around a massive protostar.
- To model the radio emission to understand the protostellar system.
Main Methods:
- Utilized the Very Long Baseline Array (VLBA) and the Very Large Array (VLA) for high-resolution radio observations.
- Conducted seven-millimeter continuum observations.
- Developed a model of the radio emission.
Main Results:
- Resolved a solar-system-sized accretion disk (130 AU diameter) around the primary protostar (G192 S1).
- Estimated the protostar mass at 8-10 solar masses.
- Identified a companion source (G192 S2) 80 AU north of the primary.
- Characterized the outflow as poorly collimated (40-degree opening angle).
Conclusions:
- The findings provide strong evidence for a true accretion disk around a massive protostar.
- The results suggest G192.16-3.82 is a binary protostellar system.
- The study advances our understanding of accretion processes in massive star formation.
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