Comets and antimatter

[Mr. Manly]

I asked this question on hazzards deep impact thread but aside from a crack from everyones favorite punk I got no replies. Perhaps some of you have heard this before.
How could comets contain antimatter surrounded by matter?
If the antimatter is just in the tail wouldn't the particles cause reactions on the scale of a nuclear bomb if they contacted matter in space.
I had never heard of this theory before Kent mentioned it in the thread. I searched it and most of the hits were for the site Kent posted and I was hoping to get another side of the story if there is one.

[MM_Dandy]

Mr. Manly,
I'm afraid that I can't help you with the anitmatter hypothesis, but I can say that I think Kent, Grant, and IDW all took the same physics course.

[Mr. Manly]

It doesn't sound plausible to me but my knowledge of comets is lacking.

[twinstead]

It doesn't sound plausible to me but my knowledge of comets is lacking.

I'm no comet expert myself, but I would be dubious as well. It seems to me that there would have to be some kind of natural containment zone (or highly advanced exotic alien technology, of course) around the antimatter so it doesn't come in contact with the 'anti-antimatter'. It seems that since we don't know exactly if or how this could happen, it sets itself up for all sorts of conjecture and bantering about of wild theories.

Actually, I guess the discovery of something like that would be a major breakthrough if we could reproduce it, but a real drag if our little probe was all it took to break the containment...

[Bob B.]

Here is a transcript of a 2003 debate between Phil Plait and Nancy Lieder about Planet X. Phil was asked if it were possible Planet X could be composed of antimatter. Here's his reply:

Well, anti-matter and matter are similar in many ways, and of course different in many ways, but some of the similarities is that if there were a ball of anti-matter, this opposite matter, floating out in space, it would look for all intents and purposes just like regular matter, it would reflect light, it would, if it were hot it would glow, just like regular matter would. And so if this thing were anti-matter we'd know. As a matter of fact, if it were anti-matter plowing through the solar system, as regular matter from the sun--protons, and subatomic particles and things--as they hit this thing, it would give off a tremendous amount of light, x-rays and gamma rays, which would be extremely obvious. So, if this thing were anti-matter, it would be even brighter than anybody would claim that any planet normally would be. There's really no way to hide an object the size of a planet. If it were so close, it would be here in a couple of days. -- Phil Plait

Of course Planet X isn't a comet, but I'm sure Phil's comments are also be applicable to an antimatter comet.

[Mr. Manly]

Thanks Bob.

[PhantomWolf]

The idea of a matter shell and an anti-matter core is pretty dumb really. There is no way to separate them from each other and so they would end up annihilating themselves. As to the guy that suggested that they could be separated by "pure energy" well all I can sugget is that he gets a cup full of "pure energy" and tries it.

[Cl1mh4224rd]

Storing antimatter would require a fairly strong electromagnetic containment field from what I understand, and also a true vacuum.

Obviously, the electromagnetic field is to is push the antimatter away from the walls of the containing object, and the true vacuum is to avoid collisions with any "loose" particles.

Not only is space not a "true" vacuum, but I don't think there's any possible, natural mechanism that would allow a comet to produce an electromagnetic field strong enough to contain the antimatter.

Also, the structure would be completely non-intuitive for a celestial body (as far as we know currently, and by our observations of comets). You have a shell of normal matter, then a gap of true vacuum, then the antimatter core. How would something like this form naturally, with such obvious order needed? The antimatter would need to condense by itself, then the matter shell would form around it, or... a matter shell would form around a "cloud" of antimatter, then shrink, squeezing the antimatter into a core. As John Stewart would say, "Whaaaa?" Order on that magnitude just doesn't seem possible, or would at least lead to super-rare occurances.

Also, if somehow the shell of normal matter were generating the electromagnetic field, we would be seeing a lot of "containment breaches" when the the shell becomes too "thin", due to sublimation, to produce a field strong enough to safely contain the antimatter. These breaches would result in tell-tale signs, which were mentioned by Phil and quoted above.

The idea just doesn't seem [naturally] possible. Of course, pointing out that it's not naturally possible would just cause the woo-woos to shift to the claim that comets are artificial constructs. In fact, I think I've seen a few random people make that claim already...

[PhantomWolf]

Storing antimatter would require a fairly strong electromagnetic containment field from what I understand

This would only work with small amounts of antimatter (usully particles but perhaps bigger) that was charaged (ie had more or less Positrons that Negatrons.)

Antimatter acts exactly like matter in its physical properties, the only difference is that it has a negitive core and a positive outer shell consisting of Negatrons and Neutrons in the nucleus and positrons wipping about it in probablity shells rather then matter's protrons and electrons.

[Lance]

Also, the structure would be completely non-intuitive...

Yolk -> White -> Shell

or

Caramel -> Nougat -> Chocolate covering

We see this in nature all the time.

And in the case of either, if the inner core contacts the outer covering you can be pretty sure there is something catastrophic happening to the object.

Maybe I should just give in and become a woo woo

[Cl1mh4224rd]

This would only work with small amounts of antimatter (usully particles but perhaps bigger) that was charaged (ie had more or less Positrons that Negatrons.)

Well, normal matter can be suspended in a magnetic field if it's strong enough (the classic "flying frog" experiment).

[PhantomWolf]

This would only work with small amounts of antimatter (usully particles but perhaps bigger) that was charaged (ie had more or less Positrons that Negatrons.)

Well, normal matter can be suspended in a magnetic field if it's strong enough (the classic "flying frog" experiment).

Suspened yes, but contained no. The flying frog is based about the magnetic field being so strong that it aligned the electrons in the frog making it magnetic, and thus when the right upwards force is applied to counter gravity it will be suspended, but if it was sat on an object so it was able to move, it could pass through the field without trouble.

In the same way you could suspend anti-matter, but any force that would move it in a specific direction more then any other would allow it to pass through the field. The only way to perfectly suspend it would be to have extremely powerful magnetic fields so that it was "suspended" equally in every direction. If one was slightly out, it would fall towards that side.

[Mr. Manly]

So phantom you're saying "it ain't happening" then.

[Frogmarch]

Anti matter is the same as ordinary matter.

In fact the only reason we call it anti-matter is because we are made of matter.

If we were made of anti-matter(and lived on an anti-matter planet) we would call the stuff we see on this Earth anti-matter. It is just relative.

so you could have ant-iron or anti-carbon or ant-any element.

You could have a playstation made up of anti-matter and place it in a chamber made up of anti-iron magnets held in place by matter magnets in a shell made up of matter.

It's not impossible but it would have to be done by an intelligent race of alien.

[PhantomWolf]

So phantom you're saying "it ain't happening" then.

Not naturally, no

[Mr. Manly]

Hahaha. It went off as planned. Imagine that. I'm going to go find Kentons thread and see if he tap dances around his theories.

[Frogmarch]

Perhaps he'll say that NASA made the impactor out of anti-matter to avoid an explosion. Put the idea in his mind and see if he goes for it.

[Mr. Manly]

As is the case with GLP, if the first doomsday scenario don't work jump on the next one.
It has now morphed into either an electrical comet or an artifical structure built by et's.
Can't wait to see what the junior astronomers club comes up with next.