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Updated: Jul 13, 2026
11:50
Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
A gaseous metal disk around a white dwarf.
B T Gänsicke1, T R Marsh, J Southworth
1Department of Physics, University of Warwick, Coventry CV4 7AL, UK. boris.gaensicke@warwick.ac.uk
Science (New York, N.Y.)
|December 23, 2006
Summary
A metal-rich gas disk was found around a young white dwarf star. This suggests that planetary systems might form even around massive stars, challenging previous assumptions about stellar evolution.
Area of Science:
- Astronomy
- Astrophysics
- Planetary Science
Background:
- The late evolutionary stages of host stars introduce significant uncertainty regarding the fate of planetary systems.
- White dwarfs represent the end-stage evolution for many stars, offering a unique laboratory to study planetary system remnants.
Purpose of the Study:
- To investigate the composition and structure of a gas disk around a young, moderately hot white dwarf.
- To determine the origin and formation mechanisms of observed circumstellar disks around white dwarfs.
- To assess the implications for planetary system formation around high-mass stars.
Main Methods:
- Observation of a metal-rich gas disk around a white dwarf using spectroscopic analysis.
- Application of a dynamical model to interpret double-peaked emission lines and constrain disk properties.
- Analysis of the white dwarf's mass (0.77 solar mass) to infer conditions for planetary system survival or formation.
Main Results:
- A metal-rich gas disk was detected around a young, moderately hot white dwarf.
- Dynamical modeling constrained the outer radius of the disk to a remarkably small 1.2 solar radii.
- The disk is likely formed from a tidally disrupted asteroid, destabilized by gravitational interaction with a planet or planetesimal.
Conclusions:
- Planetary system formation may occur around high-mass stars, as indicated by the white dwarf's mass.
- The presence of a close-in disk suggests that asteroid disruption is a viable mechanism for feeding white dwarf atmospheres.
- This finding contributes to understanding the late stages of planetary system evolution and habitability around evolved stars.
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