Overview
- Chalmers-led researchers measured polarized visible light with VLT/SPHERE and combined it with radiative-transfer modeling and prior ALMA imaging.
- Dust grains around R Doradus are typically about one ten-thousandth of a millimeter across, too small for starlight to push them into interstellar space.
- Analysis indicates the grains’ composition matches common stardust types such as silicates and alumina, confirming dust is present but dynamically ineffective.
- Model tests suggest iron-rich silicate grains large enough to be accelerated would overheat and vaporize, and the required gas-to-dust ratios contradict observations.
- With radiation pressure ruled out for this star, researchers point to giant convective bubbles, stellar pulsations, or episodic dust formation as leading alternatives to launch AGB winds.