More on C/2002V1 brightness
- First of all I would like to apologise for a mistake in a previous
post regarding the brightening trend of Comet C/2002 V1. This had a
computational error that indicated that the comet was brightening at
an inverse 4 or 5 power law as determined by an alternative
photometic method. Correcting this error I find good agreement with
Seiichi's current n=12 brightening trend. 3 further observations
from November 9, 22 and 30 also support this.
Additionally, when revisiting the calculations, I found that
intensity of the outer coma fades in good agreement with an inverse
square law. This implies that a very faint outer coma does not have
a great impact on the overall brightness of the coma. To put this in
perspective, my November 9 estimate increased from mag. 15.1 to 14.8
when raising the photometric aperture from 1' to 3' diameter.
From this I am now convinced that the current rapid brightening is
actually real and wonder if this is result of the nucleus containing
a large amount of water in proportion to other volatiles? If this
were the case then we might see the initial rapid brightening
steadily decline to a more normal power 3 or 4 rate by the time the
comet reaches 1 AU from the sun. Presumeably, then the true absolute
magnitude might be as high as 8 making the comet similiar to the two
Machholz sun-approaching comets of the mid-late eighties.