According to this article, Comet ISON - which has the potential to be one of the best comets in a long while - might be on the verge of breaking up, which would dramatically reduce its hoped-for display. So I am hoping that the diagnosis of possible breakup turns out to be wrong. But as it is, we have to just let nature take its course as ISON approaches the Sun.
Is the Christmas Comet breaking up?
Here's why the astronomers think this might be happening:
"Light signatures from ISON, which has just streaked past Mars, indicate the comet is about to break up, says Ignacio Ferrin, an astrophysicist at the University of Antioquia in Medellin, Colombia.
He explained that comets typically brighten as they get closer to the Sun, crossing a temperature threshold that causes their icy surfaces to evaporate, depositing water vapour, other gases and dust in their wake.
But, said Ferrin, the light curve from ISON slowed down and then remained practically constant, with no sign of greater brightness, as it raced forward. This is a signature that matches four previous comets that have broken up catastrophically, he said."