HD 69830 debris belt

Estimating the mass of the debris disk in HD 69830

Seems that if the disc is the same age as the star, there might be only a handful of planetesimals contained within it.

Quote :

Secondly, if we allow the stellar/disk age to be t_⋆ ≈ 1 Gyr, then decent estimates for the disk mass and number of planetesimals are produced:

M_disk ≈ 3–4 × 10⁻³ M_⊕,
N ≈ 2–3.

Multi-Epoch Observations of HD69830: High Resolution Spectroscopy and Limits to Variability

No evidence for changes in the dust amount or composition, though the new analysis does not confirm previous claims of water ice detection, and a few other minor minerals.