Believing in comet dust

Well, I have a few things to add since my Comet Kerfuffle post a few months back.  Since then I've had the chance to take some images of comet C/2012 S1, aka Comet ISON through a fairly decent sized telescope (3.5 meter).  I'm starting to believe that we are in for quite a show this fall.  Why?  Well here's my reasons to be optimistic:


1.  At about 5 AU, where Jupiter orbits, the comet already has a very pronounced coma and tail.  This is still far enough out that it isn't getting warmed all that much by the Sun, and in fact not all of the gas species that drive the coma and tail have even reached sublimation temperature yet.  As one would would expect from an Oort Cloud object making a fresh return to the inner solar system, it is a very, very active comet.

Comet C/2012 S1 @4.9AU (Hammergren, Solontoi, Gyuk)

2. Its going to pass close to the Sun.  Really close.  Close enough that the tidal and thermal forces associated with the comet's passage by the Sun may cause it to fragment.  If that happens it will be quite a show for sure.  Unfortunately from the look of the orbit that event would most likely happen with the comet behind the Sun viewed from Earth.

3.  Folks who have been tracking the observed magnitudes of this thing are saying that it is fairly odd.  Most comets brighten suddenly and then "level off" at a certain point (if you're squinting at them in the right logarithmic axis!).  This one looks like it may have already gone through this change due to the way it is increasing in magnitude.  If that's the case it isn't a wild prediction to say that C/2012 S1 is trending toward "lunar" magnitudes - potentially as bright as the Moon!

Now I'm not saying that I am predicting that this is going to be a day-time comet - it will be hidden by the Sun when it is at perihelion for instance.  Many, many things can and will change in this comet's life between now and November of this year, but the way things are shaping up I am starting to really think that this comet will be spectacular in one way or another.