I am Mikiya Sato.
I have done the simulation about the dust trail of comet ISON.
The orbit of comet is a hyperbola (e > 1), but I calculated
distribution of 1-revolution trail by having assumed the long
period, about 1400 yrs (e = 0.9999).
The dust trail sometimes approaches the earth because of perturbation
of Jupiter. But the distance is 0.0095 AU even when the trail
approaches the earth most.
The distance is too far to produce active meteor shower.
+Approach time to the earth
(UT) Distance(AU) RP (RA, Dec) Vg(km/s)
2003 Jan 15 09h 0.0119 152.8 17.5 50.9
2015 Jan 15 19h 0.0095 152.9 17.4 50.8
2027 Jan 16 00h 0.0113 153.0 17.4 50.7
2039 Jan 16 10h 0.0143 153.1 17.4 50.7
2051 Jan 16 09h 0.0176 153.1 17.4 50.7
This is the result of assuming that a dust trail exists.
But the comet has not approached the sun in the past because
the orbit is hyperbolic.
Therefore, probably, the dust trail does not exist.
So, I think no meteor shower from comet ISON.
This result was published at the bulletin of our science museum.
"An examination of the possibility about the appearance of the meteor
storm from comet ISON (C/2012 S1) "
Sato M. 2012, Bulletin of Kawasaki Municipal Science Museum,
But it was written in Japanese, verry sorry.
Maybe, you can see two figures from the following web page.
(If someone wishes, I will try to translate a summary.)
The fact that ISON’s brightness began flattening out early in 2013 did not go unnoticed, with JPL's Horizons updating their lightcurve parameters (what I use to draw the curve on the lightcurve plot we display on this website) as sufficient new data were obtained. Updates to the lightcurve parameters have continually lowered the predicted brightness. As astronomers plan their observations, these lowered expectations have been continually taken into account. We’d obviously love for ISON to outperform these projections and live up to the unfortunate hype that is still floating around on the internet. However, most (and hopefully all) observations are being planned around the most conservative estimates for the brightness.1
Furthermore, the flattening out of ISON’s brightness was not terribly surprising for a couple of reasons. First, by a quirk of the Sun-comet-Earth viewing geometry, ISON’s distance from the Earth remained nearly constant from January through June, and actually increased from mid-February through mid-May. Coupled with that, the phase angle changed from mid-January through mid-April in a way that steadily lowered the brightness. These two effects worked together to offset much of the gains in brightness that ISON made due to the decreasing distance to the Sun during the interval, and is in stark contrast to the behavior from discovery in September 2012 through January 2013, when all three effects worked in unison to increase ISON’s brightness.
Even when normalizing for these effects, ISON still hasn’t brightened as much as initial projections suggested it might. But, again, this shouldn’t have been shocking news to those familiar with observations of comets making their first passage through the inner solar system. University of Maryland professor emeritus Mike A’Hearn gave a fantastic discussion of this at last week’s Comet ISON Observer’s Workshop (skip to the 15:40 mark). For reasons that are not entirely understood, these “dynamically new” comets tend to brighten at a much slower rate than comets that have been around the Sun before. ISON’s initial rate of brightening was much higher than is typical for dynamically new comets and, sure enough, it slowed down dramatically soon thereafter.
Given the evidence that I’ve detailed above, why am I still optimistic about ISON’s prospects? Because all of the observations obtained so far of ISON have occurred beyond the “frost” line. The frost line -- also sometimes called the “ice line,” “snow line,” or “water line" -- is the distance at which water ice begins to sublimate vigorously. The distance depends on a few variables, but is roughly between 2.5 and 3.0 AU, about the distance of the asteroid belt. Beyond this distance, it is too cold for water ice to sublimate efficiently and it remains almost completely frozen. Inside of this distance, it is warm enough that water ice sublimates into a gas easily.
Originally posted by wildespace
Originally posted by ngchunter
reply to post by wildespace
Damn, he beat me to the punch. Ah well, well done Gary.
A second night of observations is needed to confirm the recovery, so you can still contribute.
Since June, Comet ISON has been hidden behind the Sun. Now an amateur imager has just recovered it low in the dawn — and it hasn't been brightening as much as we hoped. Don't bet on a fine naked-eye spectacle this December.
Sky & Telescope's longtime comet analyst John Bortle writes us:
ISON is currently about at the distance from the Sun where water ice sublimation would be expected to be taking over in the comet's photometric development. That the comet continues to appear as faint as it does implies that its intrinsic brightness (absolute magnitude) is low and that the nucleus is probably small and relatively inactive.
Originally posted by Engonoceras
I'm wondering if the recent "retirement" of the Kepler telescope is a hoax and it's actually working fine.
Does anyone know if the Kepler telescope was in a position to get a good view of comet Ison and track it more precisely?
The 2,300-pound telescope operates with four “reaction wheels,” momentum-canceling flywheels designed to keep it perfectly stable during lengthy observations of distant stars, when minute blips of light can reveal a potential planet orbiting its star.