500kg of anti-matter. How much boom-boom?

[Shroom Man 777]

How large an explosion would 500kgs of anti-matter make when they make contact with regular matter?

[Chris OFarrell]

E = MC^2 is your friend.

[Xon]

How large an explosion would 500kgs of anti-matter make when they make contact with regular matter?

Google is your friend

About 10^20 joules, which is about 21 480mt, or almost 22 GT

[Darth Wong]

That is an upper limit, not necessarily an accurate or even vaguely accurate figure. In vacuum, it is quite likely that such a large volume of antimatter when thrown into contact with matter would largely be hurled unreacted into space because of the energy released by the first portion to come into contact..

[Chris OFarrell]

That is an upper limit, not necessarily an accurate or even vaguely accurate figure. In vacuum, it is quite likely that such a large volume of antimatter when thrown into contact with matter would largely be hurled unreacted into space because of the energy released by the first portion to come into contact..

Though at a guess I think he is looking for a 100% efficient reaction assuming every antiparticle mutually annihilates.

[Darth Wong]

That is an upper limit, not necessarily an accurate or even vaguely accurate figure. In vacuum, it is quite likely that such a large volume of antimatter when thrown into contact with matter would largely be hurled unreacted into space because of the energy released by the first portion to come into contact..

Though at a guess I think he is looking for a 100% efficient reaction assuming every antiparticle mutually annihilates.

Maybe, but I've seen way too many people assume that 100% reaction is actually a reasonable assumption so it had to be pointed out. BTW, there's a big difference between antimatter and antiparticles.

[Xon]

Maybe, but I've seen way too many people assume that 100% reaction is actually a reasonable assumption so it had to be pointed out.

Yup. Anti-matter reactioning perfectly with matter on the right target is a damn brainbug.

But without more information from the OP, there isnt much you can draw from it.

BTW, there's a big difference between antimatter and antiparticles.

Very true. From how most people handle 'anti-matter' its a bunch of handwavium of some type of matter which reacts explosively with normal matter.

[Shroom Man 777]

Very true. From how most people handle 'anti-matter' its a bunch of handwavium of some type of matter which reacts explosively with normal matter.

But that's what it is. AM+M = Boom boom.

And, as most of you might've guessed, I'm asking this for my sci-fi universe, specifically for a strategic warhead that detonates within a planet's atmosphere. Oh yeah, and can't the warhead have a mechanism which exposes the AM to normal matter in a controlled way that ensures maximum bang for buck?

[Lancer]

Very true. From how most people handle 'anti-matter' its a bunch of handwavium of some type of matter which reacts explosively with normal matter.

But that's what it is. AM+M = Boom boom.

And, as most of you might've guessed, I'm asking this for my sci-fi universe, specifically for a strategic warhead that detonates within a planet's atmosphere. Oh yeah, and can't the warhead have a mechanism which exposes the AM to normal matter in a controlled way that ensures maximum bang for buck?

not really. Any mechanism you have is probably gonna be destroyed in the first few instants if it's gonna release energy on a meaningful scale.

[Xon]

But that's what it is. AM+M = Boom boom.

Antimatter has a lot more complex properties than AM+M = boom.

The over all electrical charges and minute charges have a big effect on how antimatter will react with matter.

For example an anti-matter atom with the electrons cloud stripped (aka ions/plasma) is electro-replusive to normal matter. Since both normal matter's electron cloud is negitively charged and anti-matter's nucleus is negitively charged.

Never mind that matter->energy conversion only occurs between identical types of anti-particles(or more accurately between quantum colors, "up & anti-up", not between "up & anti-down").

[CJvR]

and can't the warhead have a mechanism which exposes the AM to normal matter in a controlled way that ensures maximum bang for buck?

I suspect you will get the best results with some form of implosion bomb like modern nukes. If you drop it in an atmosphere you should burn all the AM although much of it will burn slower after the initial blast scatters it a bit.

[Robert Walper]

Out of curiousity, wouldn't 500kg of anti matter exposed to a plantary atmosphere yield 100% interaction? The entire atmosphere is composed of matter after all, and portions of anti matter blasted away from the intial blast epicentre would still react with the surrounding atmosphere, correct?

[Darth Wong]

Out of curiousity, wouldn't 500kg of anti matter exposed to a plantary atmosphere yield 100% interaction? The entire atmosphere is composed of matter after all, and portions of anti matter blasted away from the intial blast epicentre would still react with the surrounding atmosphere, correct?

No. See if you can grow a brain and figure out why.

[Robert Walper]

Out of curiousity, wouldn't 500kg of anti matter exposed to a plantary atmosphere yield 100% interaction? The entire atmosphere is composed of matter after all, and portions of anti matter blasted away from the intial blast epicentre would still react with the surrounding atmosphere, correct?

No. See if you can grow a brain and figure out why.

Because portions of anti matter would be hurled outside of the atmosphere before it could react?

[Crown]

Out of curiousity, wouldn't 500kg of anti matter exposed to a plantary atmosphere yield 100% interaction? The entire atmosphere is composed of matter after all, and portions of anti matter blasted away from the intial blast epicentre would still react with the surrounding atmosphere, correct?

Errr, yes and no.

Disclaimer; not an expert but;

Okay here's my assumptions based on casual reading;

• Anti-matter when brought into contact with ordinary matter will destroy each other, this is always true.

Well that's pretty much it for the assumptions.

Now say you have the afforementioned 500kg of anti-matter, and you detonate it - somehow - in Earth's atmosphere, as soon as there is enough energy to break apart whatever containment/holding funky thing you got going, the anti-matter is now exposed to the Earth's atmosphere. The exposed part starts to react with the atmosphere, eventually you are going to reach a point where the energy being released starts sending this AM in all sorts of directions (say it was a solid bar, or whatever).

Now everytime some of this AM hits real matter it's gonna go boom, but in the atomic level (more of the AM keeps breaking apart), there is plenty of empty space.

So this AM is going to be traveling at outrages speeds, in all directions, occasionally hitting ordinary matter.*

Now what this means is that eventually all the AM is going to react with normal matter and get destroyed, but it is by no means certain that it will do so, in one specific place, in a discreet unit of time, in order to get the 100% efficiency for the calcs.

To get what I'm thinking; imagine fireworks. You get this one big 'bang' and then some pretty lights, and then some more smaller 'bangs' latter.

Given the energy we're discussing being released, it's not unconcievable that some AM gets blown clear into space, and is driffting harmlessly until it gets hit by something.

If I'm wrong, somebody will hopefully correct me.


*Please not this also doesn't take into consideration that the atmosphere would also quite likely be reacting to the blast (moving away, or towards the blast point), it just assumes that it is always there.

This also doesn't take into account the density of the atmosphere (related to the above point, but deserves a sepparate mention), which will obviously influence reaction time.

[Robert Walper]

*snip*

Yeah, I completely forgot the fact matter is in fact mostly empty space. A quick review of Mike's photon torpedo analysis was a good reminder. Doh.

[Xon]

So this AM is going to be traveling at outrages speeds, in all directions, occasionally hitting ordinary matter.*

Its worse than that. Such an energetic enviroment would probaly strip a large chuck of the electron cloud of the anti-matter to cause the anti-mater ion to become negitively charged.

This means electro-repulsive effects will make collisions between normal air (which is largely non-ions) and the anti-mater even harder to achieve.

[GrandMasterTerwynn]

Out of curiousity, wouldn't 500kg of anti matter exposed to a plantary atmosphere yield 100% interaction? The entire atmosphere is composed of matter after all, and portions of anti matter blasted away from the intial blast epicentre would still react with the surrounding atmosphere, correct?

No. See if you can grow a brain and figure out why.

Because portions of anti matter would be hurled outside of the atmosphere before it could react?

Not quite. As mentioned before, matter is mostly empty space. Worse still, the warhead would be vaporized and largely dispersed in a fraction of a second, immediately dropping the effective yield of the bomb to maybe a half or quarter of the theoretical result. While the aggregate total yield will be pretty high, the reaction time will be much too spread out to make it do anything more than warm up the atmosphere of the planet and make things radioactive.

Second, the only particle-antiparticle reaction that has 100% energy conversion is electron/positron annihilation. Smash those together, you get a gamma ray photon with an energy equivalent to the mass-energy of the two particles. Smash any heavier particle and antiparticle together, you get a gamma ray photon, and a shower of short-lived elementary particles, which decay into other elementary particles within an instant. While the sum of their energies will equal the mass-energy of the two progenitors, much more of it will be tied up particles.

[Lord Zentei]

Second, the only particle-antiparticle reaction that has 100% energy conversion is electron/positron annihilation. Smash those together, you get a gamma ray photon with an energy equivalent to the mass-energy of the two particles. Smash any heavier particle and antiparticle together, you get a gamma ray photon, and a shower of short-lived elementary particles, which decay into other elementary particles within an instant. While the sum of their energies will equal the mass-energy of the two progenitors, much more of it will be tied up particles.

The proton-antiproton reaction produces gamma rays and pi mesons, which in turn decay into gamma rays, various speces of neutrino and electrons and positrons.

[Antares]

Second, the only particle-antiparticle reaction that has 100% energy conversion is electron/positron annihilation. Smash those together, you get a gamma ray photon with an energy equivalent to the mass-energy of the two particles. Smash any heavier particle and antiparticle together, you get a gamma ray photon, and a shower of short-lived elementary particles, which decay into other elementary particles within an instant. While the sum of their energies will equal the mass-energy of the two progenitors, much more of it will be tied up particles.

The proton-antiproton reaction produces gamma rays and pi mesons, which in turn decay into gamma rays, various speces of neutrino and electrons and positrons.

Could you please give a source for this pi meson reaction?
I am just curious

[Lord Zentei]

Could you please give a source for this pi meson reaction?
I am just curious

Live lectures, I'm afraid. No links, though others may have them.

[SyntaxVorlon]

How about 500 kg of neutronium and 500 kg of anti-neutronium?
That ought to take care of the electron stripping problem.

[SyntaxVorlon]

or 250 of each instead to fulfill the OP request.

[Xon]

How about 500 kg of neutronium and 500 kg of anti-neutronium?
That ought to take care of the electron stripping problem.

Why dont you just sling the neutronium at the planet at high speeds?

[SyntaxVorlon]

How about 500 kg of neutronium and 500 kg of anti-neutronium?
That ought to take care of the electron stripping problem.

Why dont you just sling the neutronium at the planet at high speeds?

You don't necessarily want to destroy the planet. Just blow it to hell.