We find out how long it takes for a comet to melt and ask could we ever get a cometless sky? Plus we wonder the power of plants.
At one limit, just one approach, if the comet has an extremely elliptical orbit that takes it directly into the Sun.
There are some estimates that periodic comets such as Halley's Comet will eventually melt away. Estimates vary from 10,000 years to 10 million years, and that it may have already lost as much as 90% of its mass during the last few million years.
Comets have been called "dirty snowballs", and it is evaporation of the volatiles as they approach the Sun which give comets their characteristic tails.
I think ill eat pizza on friday Bob Zimbobway, Tue, 10th Dec 2013
makes sense Andy, Sat, 24th Oct 2015
Any rocks in the comet will be left over as asteroids. Steve. Meyers, Thu, 22nd Sep 2016