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Updated: Apr 8, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
10.2K
Direct evidence for magnetohydrodynamic disk winds driving rotating outflows in protostar HOPS 358
Chul-Hwan Kim1, Jeong-Eun Lee2,3, Doug Johnstone4,5
1Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Republic of Korea.
Nature Communications
|April 6, 2026
Summary
Magnetohydrodynamic disk winds efficiently remove angular momentum during star and planet formation. Observations of protostar HOPS 358 provide direct evidence for these winds operating in the planet-forming zone.
Area of Science:
- Astrophysics
- Star Formation
- Planetary Science
Background:
- Angular momentum removal is crucial for star and planet formation.
- Magnetohydrodynamic (MHD) disk winds are a proposed mechanism for this removal, especially where turbulence is low.
Purpose of the Study:
- To provide direct observational evidence for magnetically launched disk winds.
- To investigate the role of MHD disk winds in early star and planet formation.
Main Methods:
- High-resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations of the Class 0 protostar HOPS 358.
- Analysis of molecular emission lines (H₂CO, SO, CH₃OH) to trace outflow kinematics.
Main Results:
- Observed a rotating, nested outflow structure aligned with the protostar's disk.
- Confirmed the outflow preserves the disk's rotational sense, indicating a magnetically launched disk wind.
- Derived a magnetic lever arm of ~2.3 and localized the wind-launching region to 10-18 AU.
Conclusions:
- MHD disk winds are active during the deeply embedded phase of star formation.
- These winds efficiently remove angular momentum, influencing disk evolution and planet formation conditions.
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