Antimatter close to home As anyone who follows big physics knows, the best way to trap anti-matter is with a magnetic field: that way, you can prevent the mutual annihilation that results from interactions with normal matter. Usually, you need a particle accelerator and a big magnet to grab hold of antimatter, even for a fraction of a second. However …
Though it does cause problems for satellites. The ISS has to carry extra radiation shielding for the occasions when it passes through the SAN and the Hubble Space Telescope is shut down for its passage. I'm pretty sure it was also linked to the repeated failures of a number of low-orbit comms sats.
I seem to recall one blue-sky idea a while back for a prototype of a kiloton class fusion device.
The problem is that the smallest conventional fission warhead would be about 15 kilos minimum, and be far too dangerous in the event of an accident.
However, making the warhead out of a superconducting core, then lithium 4 deuteride with an outer covering of beryllium would mean that even if a detonation occurred in the fuel pod it would not result in a big boom.
Essentially the antimatter would be used as a fusion catalyst, being accelerated using something like a linac onto the fuel pod through a small gap in the shielding.
The MgB2 superconducting inner lining would trap the antimatter for a short time then as it heated up (use a laser here) it would go normal and the antimatter would react inside the chamber and detonate the device.
Ought to work, back of the envelope calculations suggest that the antimatter required would be in the low milligrams for a return trip to Mars.
Harnessing it from the solar wind is also a possibility..
AC, because I don't even WANT to know how many classified patents this breaches.
Conventional fission warheads aren't particularly hazardous in the event of an accident; triggering a nice neat fission reaction in a warhead is a very non-trivial exercise. Sure, you could accidentally detonate it, but the same problem exists with your unicorn-fart powered antimatter confinement device. Or were you thinking about launch accidents? If you've got the magical powers to make super conductors and generate antimatter willy-nilly, you can certainly make a nice catapult that can fling payloads into orbit fast enough that even in the event of problems they won't be falling back down.
Wouldn't a hafnium nuclear isomer based system require less magic than your proposal? Or hell, a plain old laser-triggered fusion warhead probably isn't that far away. Or you know, just a normal orion drive. Even rocket science isn't exactly rocket science, these days.
So, I'm baffled, and definitely missing a lot of information when it comes to particle physics. So, matter and antimatter collide, and annihilate. What form does this annihilation take - in what form is the resultant energy? And what natural processes exist that turn energy to matter? Is it possible that the energy resulting from the collision of matter and antimatter is ever so slightly more inclined to become "normal" matter rather than antimatter? Could this explain the baffling dearth of observable antimatter in our universe?
Paris because I do not have the knowledge to address this subject, but am pretentious enough to do so anyway.
Its a pretty good annihilation. 100% conversion to energy allegedly there hasnt been enough study of larger quantities of anti matter to say outright.
Nucleosynthesis creates elements from stray protons and neutrons - but you obviously need protons and neutrons to begin with. Fusion turns energy to matter (in a manner of speaking) in nuclei masses greater than iron btu again you need constituent nuclei. I dont think scientists are aware of a conversion of 100% energy to matter though.
Regular fission turns an appreciable amount of matter into energy in the form of gamma rays, other high-energy electromagnetic radiation and a great deal of heat. The energy that matter is turned in to would be, similarly, gamma rays and other high energy electromagnetic radiation, the difference being that the conversion would be complete.
The current assumption is either that matter and anti-matter were produced in equal proportions during the big bang, but that they quickly segregated from each other, OR that anti-matter isn't quite as stable as matter, so it was less likely to form.
Google "antimatter" and "bias" for information. We may neither of us understand a word of it but it's nice to know that it's there.
However, the last that I heard, they hadn't yet found enough of a bias towards matter and against antimatter in various processes experiments to add up to what's needed to make the Big Bang work properly as far as that goes. Well, looking for it keeps them in a job.
@Jacob: "What form does this annihilation take[?]"
It depends on exactly what is annihilating. If you take 2 fundamental particles, like an electron and a anti-electron (a.k.a. positron), you'd normally get a gamma photon and an infrared photon (you need to have 2 particles out, because you have to balance all the equations: charge, momentum, energy, and several others you've likely not heard of).
When dealing with protons and anti-protons it's more complicated because a proton isn't a fundamental particle - it's a composite of 3 quarks (2 up and a down), a bunch of gluons sticking the quarks together, and a cast of thousands of virtual particles doing cameos. It is unlikely that each particle would find it's exact opposite, so instead of just photons, you get photons and a bunch of things like neutrinos being emitted, with the neutrinos carrying about a third of the total energy.
Originated from the U. Pennsylvania IIRC.
There is a paper but basically 200g (roughly golfball size) spheres (199g Lead, 1g Uranium and some Gold) are hit by multiple ion beams (or lasers, but the ion beams are more efficient to make which helps) and start to be compressed up to a fission density. Then they get hit by a small burst of anti-protons and things really start to cook.
But where to get the anti-protons? The team writing the paper reckoned 1 years production would do it but the containment traps were not up to holding onto them long enough to be ready for the deceleration burn when you got to Mars/Venus/Jupter. This is being worked on.
However if there is a *natural* (and renewable?) supply that changes things quite a bit.
Note also any *solid* object passing through that zone would be *guaranteed* a nasty dose of high energy X and gamma rays. A magnetic shield that repelled Protons, wound attract Anti-Protons.
The SAA is the weakest part of the Earths magentosphere, roughly where the field lines channel incoming particles to. The field of view of a satellite mounted camera show *lots* of bright flashes when the shutter is closed in a way it does not anywhere else on orbit.
An astonishing piece of serendipity.
They need it for the terrstrial base of an anti-matter harvesting facility beneath the SAA. I say we start building our own and send down the Ark Royal to protect our interests pronto. What's that? We no longer have a maritime force protection capability? Oh.
...If it was up there in bloody great big chunks, rather than as a rarefied ion plasma, then this might happen. As it is, things going through the Van Allen Belts get hit by the odd antiproton, causing the annihilation of a proton in the outer layer of atoms, the release of a high-energy photon (probably in the gamma ray range), and possibly making the atom that was hit mildly radioactive, depending on whether it can bear to lose a proton or not. This is kind of why they are known as the Van Allen Radiation Belts, the clue there being in the word radiation really.
Given the rarefied nature of the belts, something would have to stay up there for a serious amount of time to be annihilated by the antimatter; the orbit would decay a long long time before this ever happened.
Still, I'm not sure I'd want to spend my holidays there...
"none have experienced a matter/anti-matter explosion." How do you know?
I see my stuff go up to geo orbit, and have several bangs a year (hundreds). The bangs come from high-energy particles that make it through the spacecraft structure and hit the electronic components.
Asking the Google calculator (I am on holiday, so my calculator is not with me):
"mass of proton * (c squared) * 2" gives an answer: 3.00655461 E-10 joules. That is not very much energy really, and would increase the temperature of the whole spacecraft (Say 6 tonnes) by about the same amount as me farting in it's general direction, so it wouldn't really "explode"
As a duly appointed AC, I hereby nominate the following additional item for inclusion in the list of Reg standard units:
1 Bristol Bachelor Fart = 3.00655461 E-10 J
(Note that further experimentation may be required to confirm the conversion factor).
Example usage:
The LHC produces collisions on the order of 3300 Bristol Bachelor Farts per molecule (3.3 kBBFs/molecule)
Burning a barrel of oil will produce about 20 E18 Bristol Bachelor Farts of energy.
Israel needed to test their nukes just like every other nuclear power. They just chose to do it with the South Africans (why it happened in Indian Ocean) as I am sure they made some serious $ by doing so and its not like they have given a damn what the international community or even the US thought.
But.... isn't the earth's magnetic field s'posed to be failing and about to flip so that north is south and south is north some time soon? And when that happens, isn't there a change that all these antiprotons that are floating in the air, will drop down, hit normal matter and Marvin the Martain will have his earth-shattering ka-boom!!
Please tell me that post-PARIS, the eggheads got together and renamed the satellite in honor of Pamela Anderson!! That would be AWESOME!!
And its great that we have antimatter naturally occurring in orbit, but I have to wonder if all the space junk we have created over the years is slowly sweeping up all this antimatter.
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