New Comet: C/2012 S1 (ISON)

reply to post by whatnext21


Thanks for the post whatnext21, but as I said in the other thread, it's looking unlikely that we'll see anything in the way of meteors from ISON. If there is anything, it looks like it will only be detectable by radio monitoring as the meteoroids are so small.

Other researchers have also been modelling ISON's dust trails, and it may well be that Earth will be too far away for anything in the near future, although it's almost inevitable that Earth will eventually run into at least some larger meteoroids, but that could be many decades or even centuries away!

Dear all,

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,
vol.23, p.5-8.

But it was written in Japanese, verry sorry.
Maybe, you can see two figures from the following web page.

meteor.kaicho.net...

(If someone wishes, I will try to translate a summary.)

Best regards,

Mikiya Sato

Source: METEOROBS (The Meteor Observing mailing list)

Although a meteor shower from ISON is unlikely in the near future, there is one new meteor shower that has a real possibility of being impressive (perhaps even a meteor storm next year) as I posted here last year.

Whilst not a new meteor shower, at least one researcher is predicting strong enhanced levels of Perseid activity in 2016, and also 2028 though not quite as strong as 2016. This year's Perseids are also looking quite promising incidentally.

With all the comets and meteor showers due in the next few months/years I think star-gazers are in for a real treat anyway!

Billed by NASA as the comet of the century, from the latest info I saw, this object hasn't even got a tail. And can anyone explain to me that the closer the comet gets to us, the less we see. On ther other hand, Jim McCanney seems to be quite excited about the 'whole world' witnessing this monster comet in November. Thus, I suspect than McCanney is in league with NASA and just spouts disinfo.

Reviewing orbit diagrams, looks like the period between Christmas and New Years will be best viewing opportunity if the comet survives its trip around the Sun, and if we don't have clouds obscuring our views of the northern sky

ssd.jpl.nasa.gov...

reply to post by MuzzleBreak

It looks like on Oct.2nd thru 5th Comet ISON will come close to Mars.

Just an observation. I wonder if Mars will get an ISON meteor shower?

Surprised this thread has remained idle for so long! DOOM PORN to the max and hardly anyone here cares anymore, the whole Dec. 2012 prequel to the real thing wore them down or they are mindless robots now. ATS had died and the world will die with it soon, no big deal, move along! Peace and Godspeed, Xenongod

P.S. Better move this to the Survival forums soon!

Here are a couple of links for updated information on the ISON Observing Campaign

CIOC

Dated August 7, 2013...from the above link CIOC Why I Am Not Particularly Concerned...

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.

JPL Orbit with Stereo A & B Positions

Is this the comet that is supposed to get really close to Mars?

reply to post by whatnext21


Good link and great quote. I remember going through this with Comet Kohoutek in the early '70s. The MSM loves to over-sell comets, then the public blames scientists when the comet doesn't live-up to their ridiculous expectations.

"The only thing new in the world is the history you haven't learned yet."
-- Harry Truman

Originally posted by rickymouse
Is this the comet that is supposed to get really close to Mars?

No, that one is C/2013 A1 (Siding Spring).

reply to post by rickymouse

No this is a different one C/2013 A1 (Siding Spring) is the one to pass close to Mars, although ISON makes a close pass over Mars this year on 2013-Oct-01 17:23 at a distance of 0.0724561740314934 AU, Siding Spring does not make it's pass until 2014-Oct-19 18:41 at a distance of 0.000821096887836991 AU

How about 5 comets for 2014?

ISON, which has been unobservable for a while due to being behind the Sun, has been recovered by an astronomer Bruce Gary: www.brucegary.net...

He used JPL and MPC projected data, as well as his own telescope, and was able to pinpoint ISON in his images.

His long-term goal is to determine ISON's rotational period.

reply to post by wildespace


Damn, he beat me to the punch. Ah well, well done Gary.

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.

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.

I tried to get it this morning in Florida just a couple hours before he did. I didn't detect it at all; there's just too much light pollution that close to the horizon for me to detect it. I drove out to an island where the skies are dark, but the mainland is to the east so you're still battling a lot of light pollution for objects low on the eastern horizon. If I drove out to the east coast I might have a little more lucky, maybe, but it's still a long shot and I won't have time for a drive that long tomorrow morning. Maybe this weekend, but by then it'll already be confirmed. Gotta hand it to him, he really pulled off an incredible shot.

Seems like ISON is looking disappointing again. www.skyandtelescope.com...

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.

But I still have my fingers crossed. Comets are like cats, they do their own thing.

Update:

Bruce Gary has imaged ISON again (Aug 16th) and estimates it to be about magnitude 14.1. So the comet might be about a magnitude fainter than hoped. Now we just need to wait and see how much activity increases as it crosses the frostline around August 20th.
www.brucegary.net...

Source



P.S. I totally pwn the Space Exploration forum! :-p

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?

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?

Kepler has been ailing for a long time now, no it's not a hoax. There are plenty of scopes to track ISON, they don't need Kepler for that. In fact they've organized an entire campaign of both professional and amateurs to help track it. I signed up for that myself. ISON is performing far under the initial projections and may not even survive perihelion. It will still be an interesting object to study, perhaps even more so if it breaks up, but I really don't see a reason for them to fake Kepler's problems in order to "secretly retask it." Kepler is in an earth-trailing orbit, so we get to see the comet emerge from behind the sun sooner than Kepler would.

Thanks for clearing that up! Yes, I read it's been having problems.

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.

I guess it must be looking at such a distance that even a micro millimeter of variance looses the object being watched.

*puts ATS conspiracy cap on*

Could ISON be an alien craft? Recently-released Hubble image of ISON reveals strange symmetric / winged object: www.youtube.com...



Here's the browsable image: hla.stsci.edu...

Move the view to the comet (to the upper right) and click "Darker" button until you see the structure.



What are your thoughts on this?