ALMA images reveal possible dust-trapping vortex in HD 34282’s protoplanetary disk

Star system: HD 34282 | Distance from the Sun: 1007 light years

HD 34282 is a young star surrounded by a disk of gas and dust, where planets may be forming. Using the ALMA telescope, astronomers captured detailed images of this disk at several wavelengths, revealing a bright arc and a complex pattern of rings and gaps. These features help scientists understand how dust and gas behave in planet-forming environments.

The observations show that the bright arc has a lower spectral index than the surrounding rings, suggesting that dust grains are growing larger or are more concentrated there. The arc’s width gets narrower at longer wavelengths, which means bigger dust grains are more tightly packed, or the disk is more transparent at those wavelengths. At the shortest wavelength, the arc’s peak shifts slightly in the direction of the disk’s rotation, and the near side of the ring appears dimmer, likely due to temperature or optical effects. These findings match predictions for a dust-trapping vortex, a swirling region that can collect dust and help form planets.

Key findings
- ALMA images reveal a bright arc and multiple rings and gaps in HD 34282’s disk
- The arc’s properties suggest enhanced dust growth or concentration, consistent with a vortex
- The arc becomes narrower at longer wavelengths, indicating tighter dust confinement
- A small shift in the arc’s peak at the shortest wavelength matches vortex model predictions
- The near side of the ring is dimmer at 0.9 mm, likely due to temperature or optical effects

Scientific study

Multi-wavelength ALMA Imaging of HD 34282: Dust-trapping Signatures of a Vortex Candidate (external link)