Out is the long-held view of hardened, dirty snowballs hurtling through space. In is the comet as a fluffy ball of powder, blowing puffs of dust whenever sunlight falls on it.
Hahahaha... I think Mel Acheson and the Electric Universe people have hit a home run.
Now the astronomers propose a fluffy ball of powder... and exactly what mechanism do they postulate to "puff the dust," sunlight allergic Magic Dragons????
Maybe playing the song would help. ;')