ISON break apart

reply to post by AndyMayhew


Good question.

Couldn't tell ya. I don't necessarily believe any of this is going to happen. Personally, I don't see any real threat from this comet.

ah....

ISON is a "target"! we know it is there and we know it will come near us.
But one cannot assume that a comet/meteor/asteroid series of dreams about ISON! behind ISON are who knows how many more rocks, many will have only weeks to be Known about, before they near earth.

one cannot even assume an object raining Down is a rock! a few nuclear missiles will ruin your day!
how about 2000+ missiles?!

I once had a very vivid dream where ww III would "happen" in 2014.
[lets see now..a race between Armageddon and apocalypse! who will get us all first.

if we all get by these and the Seers really see to the events of the year 2087, then Mr Death will pay a call for you.

where there is smoke there is fire and there are a *LOT* of these dreams and visions happen now all at once. seems now there are even more than for the pre-2012 period!

something is Up!

freestone

reply to post by freestonew


Food for thought. Thanks for your input.

reply to post by freestonew

we know it is there and we know it will come near us.

Correction: We know it is there and we know it will not come near us.

reply to post by Phage


The odds would say you're right on that one. Some posters think it's physically impossible for any of it to hit or come closer to Earth, but I don't think that's necessarily accurate. I have somewhat of a decent understanding of orbital mechanics, and I understand if it just split apart it would maintain the same essential trajectory.

The only thing I really have to say is we simply don't know the chemical composition of this particular comet down to the T.

reply to post by 1Providence1

I'm not sure what the exact chemical composition has to do with orbital mechanics.

But you are right, the "odds" are that I'm right. Unless you can provide a method whereby a comet could obtain a sufficient change in velocity (delta V). It's not easy to alter the velocity of something that's falling toward the Sun at 33kps and masses in the hundreds of trillions of kilograms. That is an awful amount of lot of momentum. It's a mountain that's moving at 74,000mph. It would take an an awful amount of energy to change its path even a little bit much less enough to cause it to get close to Earth.

And it's falling faster all the time. It's going to be moving at something like 183kps at perihelion, that mountain is going to be moving at 400,000 miles per hour! It's a runaway train on a track determined by gravity. It's going to stay on that track.

Space Weather had an article that they think that it's breaking apart.
Something to do with the color telling them that ....
But still not coming near Earth ...

reply to post by Phage


and when it splits apart, even without any explosion as someone here suggests, the gravitational forces influencing the path of every separate piece, will be entirely different than the force influencing that comet as a single object, am i right? it may have neglible influence now, but when the comet will be flying around the sun - the smallest change in gravitational forces will accumulate along comet's path.

the comet has its mass, when split apart, every single piece has its own mass - smaller than the mass of the whole object, obviously - and while the comet's velocity won't change, and the sun's mass won't change, the whole equation will split apart into separate equations for every single piece of the comet flying around the sun, and while the change may be subtle, i wouldn't be so sure if it won't accumulate enough for some of those pieces to hit the earth. it's just a guess, but there are to many variables imho in case of the comet split - how it'll split, when it'll split - to just negate such possibility.

unless, of course, you can provide a mathematical proof to negate my post entirely - i'm more than willing to see it, honestly.

reply to post by jedi_hamster

and when it splits apart, even without any explosion as someone here suggests, the gravitational forces influencing the path of every separate piece, will be entirely different than the force influencing that comet as a single object, am i right?

No. The pieces will continue on same orbit as the original object.

unless, of course, you can provide a mathematical proof to negate my post entirely - i'm more than willing to see it, honestly.

The number we want is the rate of acceleration due to gravity. This is the number that determines the shape of an orbit. That formula is the Gravitational Acceleration Formula:

g=GM/r^2

What happened to the second "M"? It goes away because we are combining two formulas; the formula for the force of gravity and the Universal law of gravitation.
www.physicsclassroom.com...

The shape of the orbit won't change. You can put a marble in an orbit the same radius as Earth and it will continue to follow that orbit (all other things being equal). We can thank Kepler for first showing us that fact and Newton for showing that it would happen no matter what solar system you were in. And let's not forget Galileo who figured out that the mass of an object does not affect how it falls.


Now, over time the orbits of the separate chunks will start to change because of various sort of random factors. Outgassing (like little rockets) will cause changes that can't be detected now, but when and if the comet comes back will result in a very slightly different orbit. The influences of the planets will have similar, very small effects over a long period of time. But it is more a matter of the pieces slowly drifting apart, not going off on very different orbits.

reply to post by Phage


noted, thanks. i knew about the g and that one kg of sugar and a tank will fall with the same speed on a body without an atmosphere, but i didn't see the orbital movement as a 'free fall'.

meh, i obviously didn't do my math today.

reply to post by jedi_hamster

Yup. Free fall. "Weightless". Falling into the Sun, but missing.

reply to post by Phage


More than likely yes, and the facts you present are indeed correct.

I was more thinking along the lines of a CME hitting the comet dead on when it's on the way around the Sun, or the nucleus of the comet having combustible materials that, when undergoing the intense energy of the Sun, would literally make the comet explode a part, which I'm sure would change the trajectory of the various pieces, no? That's the theory behind setting off huge nukes on an Earth bound Asteroid to change it's trajectory right?

However, like you said, it would take one hell of a lot of energy to get it close to Earth, so the scenario is highly unlikely. I agree with your conclusion for the most part.

reply to post by 1Providence1


well this "little" article here:
astronomia.udea.edu.co...

says he is about to break apart... strangely, it's taking to long in comparison to the statistical data (known till now (max. 90 days) Ison is taking 9 months)

voyger2
reply to post by 1Providence1

 

well this "little" article here:
astronomia.udea.edu.co...

says he is about to break apart... strangely, it's taking to long in comparison to the statistical data (known till now (max. 90 days) Ison is taking 9 months)

edit on 4-10-2013 by voyger2 because: (no reason given)

Great info. So they seem to have recognized a pattern in the light curves suggesting ISON is going to disintegrate. However, they also mentioned how it has taken much, much longer than comets Honig and Tabur for the full disintegration to occur.

We shall see!