Measurements of how light from VY Canis Majoris is polarised by the surrounding dust grains show that the dust grains around VY Canis Majoris are relatively large, about 0.5 micrometers in size. Although that may appear small, it is approximately 50 times larger than the average size of dust grains in interstellar space. These dust grains are sufficiently large to be accelerated from VY Canis Majoris by the star’s own radiation, thereby contributing to the star’s prodigious rate of mass loss.
VY Canis Majoris will eventually explode as a supernova. The large size of the dust grains allow them to be accelerated sufficiently far from VY Canis Majoris, making them resistant to sublimation in the ensuring supernova explosion. The large dust grains, together with the heavy elements created during the supernova explosion will go on to form subsequent generations of stars and planets.
Reference:
Scicluna et al. (2015), “Large dust grains in the wind of VY Canis Majoris”, arXiv:1511.07624 [astro-ph.SR]