To Boldwood women had been remote phenomena rather than necessary complements—comets of such uncertain aspect, movement, and permanence, that whether their orbits were as geometrical, unchangeable, and as subject to laws as his own, or as absolutely erratic as they superficially appeared, he had not deemed it his duty to consider.
There are no more uses of "comet" in the book.
Show samples from other sources
I look under the sink and find a dried-out Brillo pad and a can of Comet.
Lauren Oliver -- Before I Fall
Three of us had giant camping flashlights, the glow illuminating jarring images: It was suburbia, post-comet, post-zombie, post-humanity.