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Antimatter Space Drive
sckienle writes "Space.com has an article on using anti-matter for propulsion in space. It isn't true Star Trek warp stuff, in fact it is a variation on an fusion based pellet design I saw in the late 70's, but interesting concept. The concept is still somewhat of a dream, as stated in the article: 'The real hub is the storage [of antimatter]. There's a lot of technology between here and there.' Later on it also mentions that we can't produce a lot of antimatter efficiently yet. Still it might be worth the effort if the theoretical acceleration proves out." The BBC has a story about studying antimatter in a lab.
That is quite possibly the most circuitous way I have ever seen someone admit that something is impossible. Fascinating.
Dr. Joseph Hairston
Superintendent, CCBC
It isn't true Star Trek warp stuff, in fact it is a variation on an fusion based pellet design I saw in the late 70's, but interesting concept.
Are you sure those aren't tracers from the bad acid you took back in the late 70's?
I don't think anyone is arguing that antimatter would be just unbelievably useful to spacecraft, but the cost needs to be taken down by something like nine orders of magnitude -- the currently going rate for antiprotons is something like a million dollars per nanogram.
The cooling ring only helps you once you have antiprotons to cool down to antihydrogen. Right now the production of antiprotons itself is just too expensive.
We'll see antimatter missles :(
I mean, come on - why not post Linux vx. MacOS X and Emacs vs. vi stories while you are at it.
sic transit gloria mundi
"Later on it also mentions that we can't produce a lot of antimatter efficiently yet."
We'd be able to produce tons of it by now if the frickin' Vulcans didn't hold us back!
-- "Government is the great fiction through which everybody endeavors to live at the expense of everybody else."
"It isn't true Star Trek warp stuff, in fact it is a variation on an fusion based pellet design I saw in the late 70's, but interesting concept."
so are they feeding those hamsters special pellets to make them run faster on the little wheel pushing the craft or are the waste pellets used for powering and propelling the ship?
...At least to provide thrust for a vessel of any kind since it costs more energy (incredibly more, with current technology) to produce than it actually stores. The only advantage to using an antimatter/matter reaction as a propellant is the sheer efficiency of the reaction. You get a lot more push out of a lot less 'fuel'. If you can get away with carrying less total mass, then you don't have to accellerate or decelerate as much.
The next Slashdot story will be ready soon, but subscribers can beat the rush and slashdot the links early!
Faster, better, and cheaper than all the other antimatter drives we have already produced?
Any sufficiently simple magic can be passed off as mere advanced technology.
Thanks to movies and television series such as Star Trek and especially Star Wars, most people have no idea just exactly how far another star system is.
The closest star is Tau Ceti, which is 4.7 Light years away, would still take a decade to reach and a decade to return even with a very, very, very advanced anti-matter engine -- a space shuttle with chemical engines, in comparsion, would take 100,000 years to reach there.
Anti-matter still costs approximately 40 quadrillion dollars per gram to make, and storing it and dealing with the gamma rays is quite another thing.
Sorry, sci-fi fans: we will never visit another star system in our lifetimes, and probably not even Mars with the amount of funding that goes to space.
This work is important because it will enable us to understand why there is any matter at all in the Universe. This is one of the great mysteries.
Yes indeed, the antimatter-matter is interesting also because - it makes use remember that a big part of our current understand of science is based on just assumptions. Rules, that exist because they have made sense (so far). One day, when we learn more, many of these rules might get obsolete.
Accelerating this way, Howe's vessel could reach a speed of 260,000 mph
Faster than light!
Would it kill them to be a little more precise on:
- the distance from the Sun to the Oort cloud (about 250AU)
- the distance from the Sun to Pluto (about 40AU)
- the ratio of those two distances (apparently about 5)
?--
E_NOSIG
Actually, it's Alpha Centauri at about 4.2 light years.
Bill - aka taniwha
--
Leave others their otherness. -- Aratak
The poster is a little confused about the speed of light. 186,000 miles per SECOND is the correct figure, 3600 times faster then the 186,000 miles per HOUR that the poster assumes is light speed.
Again, please note, the max speed was 260,000 mph, an acronym for miles per HOUR.
Warp Drive works by pushing space against itself through the use of warp fields, has nothing to do with matter.
Didn't you take warp field theory 1000 at Starfleet Academy?
in the case of antimatter propellant, instead of a reactive force, the propellant will just annhilate the surrounding matter
While this reasoning is completely valid. They are not proposing simply injecting antimatter into a combustion chamber. The point is that they will use antimatter in combination with matter (similar to the way they use both oxygen and nitrogen in today's spacecraft). That way the inject matter and the inject antimatter ahihilate each other, causing a large release of energy which propels the spacecraft forward.
neurostarDoesn't the Enterprise use Dilithium crystals for it's warp drive, not anti-matter?
--
"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
Actually, you're both wrong. The closest star is the Sun. But that's just me being pedantic.
XML causes global warming.
One side-effect of anti-matter drives is making self-destruct much, much easier.
Example: a dude sitting on a sled on a frozen pond, with a sackful of bricks. When he throws a brick off the sled in one direction, the sled moves in the other direction. Because there is very little friction between the sled and the ice, the sled keeps moving. Throw more bricks, and the sled will go faster.
To make everything clear: the sled is like a rocket, the bricks are like fuel, and space has even less friction than a frozen pond. Because the total momentum of the system must be conserved, as fuel is burned and exhaust is generated, the rocket moves forward.
In a just society, where the wants of the underprivileged are not left unattended-to, in a truly accepting and broad-minded multicultural community where spiritual values and emotional resonance are cherished and rewarded, it's clear that the hierarchically-constrained "male physics" which enforces today's high antimatter prices would cease to obtain.
I invite you all to contemplate the joys and rewards of a non-judgemental, people-centered physics, which takes emotional and spiritual considerations are factored into every equation. With such a "physics of the heart" taught as a scientifically acceptable and morally rewarding alternate truth -- for there are always many mutually exclusive and identically valid truths, especially in matters of radiation -- adequate supplies of antimatter would be within the reach of all! Imagine every child having enough antimatter to dream and to grow, to achieve his or her full creative potential as an individual, regardless of his or her astrological sign!
Is it truly so radical, to contemplate making science the servant of humanistic values, rather than their enemy? Is it really necessary for antimatter, like the so-called "Western literary canon", to be the exclusive province of dead white males? I think not.
"Offtopic, Inflammatory, Inappropriate, Illegal, or Offensive" -- hey, that's me!
It topped out at 3,492,901 MPH, and then the impact of space dust turned their little umbrella thingy inside out. Now they're trying to figure out how to stop the damn thing, by firing a cold fusion cannon out the front...
I suspect a good source of brownian motion, like, say , a nice hot cup of tea might help...
the above is my personal opinion and does not necessarily reflect that of the little voices in my head
Any physicists out there? Why is antimatter so hard to produce? What I know about the matter is limited to the following - (please correct me if you have the appropriate knowledge)
1. The amount of antimatter currently visible in the known universe is negligible compared to the amount of matter.
2. However, in the big bang, antimatter and matter are supposed to have been created in equal amounts. So where did antimatter go?
3. QED equations for antiparticles are exactly the same as those for normal ones if you reverse the direction of time.
The only conclusion that *I* can draw from this is that there is no antimatter left nowadays because it is travelling in the opposite direction in time, whatever that means.
That in turn gives a simplistic explanation of why it is hard to create antimatter - there is no causal relationship normally. According to my weird intuition, you can only create antimatter in a material universe by violating 'normal' causality.
PS. I am *not* a physicist.
I miss my rubber keyboard.(Homepage)
No.
The protons and antiprotons would react, producing two photons. Figure out how to reflect the gamma rays in one direction, and the ship will be accelerated in the other direction. Light has momentum (E=pc).
This is why they are using a sail on this design. Spread the reaction out over a large surface and the the radiation intensity won't be as bad.
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Basically, warp drives are run off antimatter -- but dilithium is the only known substance that doesn't react to antimatter, when subjected to an EM field. So the dilithium just processes the antimatter.
(in voice that gets more and more mouse like as we keep speeding up towards the speed of light)
Capt'n Kirk, she's flying appart
-- Scotty
That is what we'd be saying once this thing was traveling faster than the speed of light!
C'mon people, some simple physics here!! We can not travel that fast! Also, consider that with the nuclear blasts they are talking about, which would blow the sail right off of our little space craft!
Damn kids and their buzz words!
HallmarkOrnaments.Com
My exception safety is -fno-exceptions.
Last time i checked, it took megawatt-hours of electricity and an expensive atom-smasher to make one microwatt-hour worth of antimatter. Without a fantastic advance in antimatter production technology, talking about *any* use for non-microscopic quantities of antimatter is just blowin' smoke.
It would be workable to pump the megawatts into a bank of lasers and let the lasers push on the probe's small light sail. (And you could tap the military budget for a good hunk of the cost of those space-based laser batteries.)
It's easy to make up & spread cool- and credible-sounding stuff. Finding & checking hard facts is hard work.
We all know how rockets work: propellant is shot out the back of the rocket engine, and as it pushes off surrounding matter, the reactive force propels the vehicle forward according to Newton's third law. However, in the case of antimatter propellant, instead of a reactive force, the propellant will just annhilate the surrounding matter, and nothing will happen to the vehicle. In fact, an antimatter rocket would only work in an antimatter universe, and in that case it would be no more powerful or efficient than our current rockets.
While I have not read the details of this idea, it is not theoretically impossible with an antimatter drive.
There is no higher law of nature that says that antimatter must be anihilated in our world - it is just the likely outcome if it comes within the proximity of normal matter. It the antimatter is handled with enough sophistication (for example, kept at bay by EM forces) it could be eventually be thrown out of the spacecraft (thus propelling it by Newton's 3rd).
Even if the antimatter was anihiilated the resulting energy could be harnessed to throw away something else (for example ions in an ion propulsion system).
Tor
Example: a dude sitting on a sled on a frozen pond, with a sackful of bricks. When he throws a brick off the sled
Te ice breaks and he sinks....thus, never posting about his high school physics class again.
That's only currently. Give it time and C will be further than A and B and then the debate will really heat up (A no B no... hang on, what year is it?:)
Actually, that's one thing I've been wondering for a long time: what are the orbital periods for the Alpha Centauri system?
Bill - aka taniwha
--
Leave others their otherness. -- Aratak
There are already numerous propulsion ideas that are not only feasible but much better than anything that is used today.
The issue is that anything inolving nuclear power is a political impossibility, at least for another generation. Antimatter drives have exactly the same issues (hum... or maybe this is not widely understood... 'antimatter' sounds much better than 'nuclear'...)
Tor
.. gee.. i started to go all WTF after seeing the title. and then the word storage..
i guess one shouldn't be staying up too long after donating blood.
world was created 5 seconds before this post as it is.
...it would seem to me that they have the right idea. They used a crystal of sorts(dilithium) to regulate the matter/antimatter reaction. Here's the reality check:
Since matter/antimatter reactions cause 2 gamma-frequency photons to be thrown off at right predictable angles to the impact vectors of the original matter and antimatter particles, an engine could be designed that ensured that one of the 2 photons always exited from the engine exhaust port to propel the ship. What of the other one? Position a crystal in the appropriate location to catch the second photon. Depending on the structure of the crystal, the result would either be mechanical (heat or vibration) or electrical energy which could be converted and/or stored as needed.
:)
.sig -- apparently he's the superintendant of a community college. Which is a perfectly respectable thing to be, but I suspect that he's a marginal Ph.D. in a non-technical field who has a bug up his ass about not having climbed further up the academic ladder.
Out of curiousity, I checked the link in his
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
I remember reading about it several times here on slashdot and it sounds very star trekish. Could someone with a physics background tell me if its possible to have one anti-proton and a regular proton that can change to an anti-proton through quantum entagglement?
Perhaps we could replicate anti-protons and anti-electrons using this technology on standard particles.
I believe this was already demonstrated in 2000.
http://saveie6.com/
wouldn't it take just as much force to bring one of these babies to a stop? At the type of speeds they are talking about, wouldn't deceleration be a couple of month process?
Our universe itself keeps on expanding and expanding
In all of the directions it can whiz;
As fast as it can go, that's the speed of light you know,
Twelve million miles a minute and that's the fastest speed there is.
Actually eleven million miles a minute is closer, but it wouldn't have fit the meter of the song as well.
Hey kids, there's only 5 days left 'til Yak Shaving Day!
(Given that the ship must not be reaching relativistic speeds for most of the journey if it is taking 10 years to go 4.7 light years.)
The cake is a pie
I don't think there's any avoiding a mechanical effect, because momentum must be preserved. In fact, in your scheme it's the photon you catch that propels the ship. The one that goes out the "exhaust" carries away the useless wrong-way momentum. Now the problem is: What can absorb those photons without quickly becoming hot enough to vaporize?
Reading the article might be helpful. The concept doesn't use the reactive force of propellant leaving the vehicle. Instead, the vehicle is driven by lobbing antimatter toward a "sail" extended from the front of the vehicle. The sail is propelled by two forces: that from the reaction of the antimatter with the matter in the sail, and a secondary fission reaction with fissionable material impregnated into the sail. In effect, the sail just drags the rest of the vehicle along with it.
However, one thing I would be concerned about is the fact the space is not really a perfect vacuum. There *is* matter out there. What happens when the antimatter stream encounters other matter in space? I presume the rest of the vehicle would have to be built to withstand a nearby "misfire" in that case.
GreyPoopon
--
Why is it I can write insightful comments but can't come up with a clever signature?
According to the article, a vessel using this antimatter engine could reach a speed of 260,000 mph in four months. This converts to an acceleration of roughly 0.0112 meters per second^2.
I think the goal should be for the interstellar starship to accelerate at 9.8 meters per second^2. This would allow to craft to simulate Earth's gravity for its occupants. Once the ship reached the halfway point, they could turn around and accelerated at 9.8 meters per second^2 in the other direction, thus coming to a complete stop upon reaching the destination.
-Jason
I hope slashdot.org isn't moving onto the same server as anti-slashdot.org! They'll annihilate each other!
Disconnect your television. Do your own research. Draw your own conclusions. They're probably lying. Don't be a sheep.
1. The problem is, there just simply isn't a large enough sample size at different frequencies of gamma radiation to make any sort of determination about the distribution of antimatter. The number of particles detected varies based on solar activity levels, etc...
2. I believe the most popular theory now is that the distribution of antimatter galaxies is in other galactic clusters... therefore, we don't see much evidence in our immediate neighborhood.
3. There are actually many different ways of decaying matter to produce antiparticles... the problem is most of these take place in the nucleus, where they are quickly annihilated, and most of these are at higher energies than is common today.
Romeo & Juliet for 1337 hax0rz! http://www.redcoat.net/pics/romjul.swf
In Master of Orion, the antimatter drive counted as a serious technological advantage. I could colonize stars that were 7 parsecs away ;o) Plus increased mobility in combat.
I think better than that was singularity drive. Something with a black hole formed in the proximity of your spaceship (a la "Event Horizon").
BTW, I'm talking about MOO 1. The first and still the best.
Sigged!
That observation is causing quite a bit of consternation in the world of physics. There are some interesting theories about this, but no one is really sure just yet.
Boobies never hurt anyone. - Sherry Glaser.
I can't believe no one modded this +1, Funny. The poster is obviously joking. Has no one here ever read the old NY Times editorial which stated that space flight is impossible because there's "nothing to push against" and said that Robert Goddard "seems to lack the knowledge ladled out daily in high school"?
Hey kids, there's only 5 days left 'til Yak Shaving Day!
I found ths in the previous article and I just couldn't go on without posting this...too darn funny:
....Upon reaching orbit mission commander Sergei Zalyotin, flight engineer Yuri Lonchakov and European Space Agency astronaut Frank DeWinne were thrown forward into their seat straps as their spacecraft separated from its booster.
A toy mouse connected to the end of a string could be seen suddenly floating as Russia's traditional cockpit "gravity sensor" again worked well.
With Zalyotin at the controls, the Soyuz-TMA spacecraft -- the capsule and rocket share a similar name.....
So why not just use HAMTARO?...those crazy Russians.
Live for the present, learn from the past, and dream of the future!
I have some concerns about a matter-antimatter propulsion system.
What happens if the matter/antimatter mix is not correct? Will we end up with something akin to that Martian from the Warner Brothers cartoons describes as a big ka-boom?
Such an explosion could make the most powerful thermonuclear device tested on Earth seem like a minor incident in comparison.
Oh. Never mind.
So antimatter is a very compact storage of energy, but we just can't produce it efficiently.
The Raven
The Raven
>as it pushes off surrounding matter
My high school physics teacher actually thought rockets worked that way. She couldn't figure out how they can work in space where there's nothing to push off of.
We had a good football team, though.
- Have a picture
It's amazing how many people felt the need to correct you after you admitted it was a mistake - before they even started.
There are 8 replies right now telling you how fast light really is. I think you should reply to them all personally, just to thank them. They certainly deserve it.
I got my Linux laptop at System76.
The article mentions that the speed of the antimatter/fission rocket will reach 260,000 mph in 4 months.
.039% of c.
That's
I guess there's a lot of room at the top, too.
First, antimatter "explosions" are actually fizzles, because P-barP reactions at rest tend generate neutral and charged pions and kaons, and neutrinos.
Neutrinos don't interact significantly with matter, so that energy is effectively lost. The neutral pions and kaons interact with the weak force only, and hence carry energy away for quite a distance (kilometers for pions) before they decay into something that does interact with matter. 50% of the time for every charge particle you get m neutral particles, where m>2 (see references
That means that most of your energy is carried kilometers or more away (for the relativistic ones) before decaying into energetic particles that DO cause things to go boom. The energy of the antimatter tends to be dispersed through a rather large volume.
Antimatter is, however, extremely valuable for rockets, due to a unique advantage. The general Hohman-transfer equation, which governs interplanetary flight, has a term exp{V/V0}, where V is the exhaust velocity and V0 is the "mission velocity", defined to be the delta v necessary to achieve a particular orbit.
For example, V0=11.2km/sec for orbit, and ~29km/sec for Saturn. Note that getting into Earth orbit gets you almost halfway to anywhere.
The propellant/load ratio, which is how much propellant per unit of mass you need to get somewhere, therefore depends (exponentially) upon the ratio of V/V0. Now, V is limited in chemical rockets to be at best 7.4 km/s for O1/LH2, so you have a built-in, exponentially growing ratio of rocket fuel you must carry per kilogram of payload. This makes manned flights to Saturn impractical with chemical rockets.
However, an antimatter rocket has no built-in limit on exhaust velocity. Solving the equations, that means that you can get to anywhere on an antimatter rocket with a fuel/payload ratio of 5:1. That doesn't sound great, but it's much better than 100:1 for orbit or 300:1 for interplanetary flights.
And, in fact, with antimatter rockets you can start *thinking* about not using Hohman transfers (which minimize the necessary energy) to get someplace, and can consider minimizing your time instead. You'll need the same fuel ratio, just more antimatter to increase your exhaust velocity V. Forward has a design for a basic antimatter rocket he did research on for the USAF.
Finally, there are ways to store antimatter for weeks at a time, using Pfenning traps and other magnetic facilities.
Antimatter, however, makes a lousy energy source, as it must be fabricated, you get less out of it than you put into it (we're currently
But it's a wonderful rocket fuel.
--Adam
"Invincibility is in oneself, vulnerability in the opponent." --Sun Tzu
and by crystal, you mean magic little rock.
The Kruger Dunning explains most post on
...was named Orion, and featured in the Larry Niven/Jerry Pournelle novel "Footfall".
I could list a whole load of links, but
a) You can find them yourself if you're interested; and
b) I can't be arsed
This sig left unintentionally blank.
Which experiment has been done that moves particles faster than the speed of light? That would be rather big news...
We could just use some of the anti-matter to get rid of some of the population AND get energy from it as well!
We do not live in the 21st century. We live in the 20 second century.
European scientists have carried out the first experiments on antimatter.
Wrong. They've been experimenting with antimatter for years. I think Carl Anderson's 1930s work was the first. This isn't even the first experiment with antihydrogen, or cold antihydrogen, for that matter.
Researchers in Geneva, Switzerland, have been able to trap and control anti-hydrogen atoms in a chamber at a sufficiently low temperature to begin studying their physics in detail.
Wrong. They haven't trapped it. Nor can they study the physics in detail yet.
Now they say they can store these fragile objects for study as well, allowing them to conduct simple experiments.
Wrong. They can't trap them, much less store them for any length of time.
By measuring the strength of the electric field, they hope to tell how tightly an anti-atom is held together and shed light on the differences between normal matter and antimatter that might explain why the Universe exists in its present form.
Not quite. They are able to tell how tightly these particular positrons are bound to their antiprotons, which reveals what quantum state the antihydrogens are in; this doesn't tell you anything about the properties of antihydrogen.
Cern physicist Jerry Gabrielse...
And, um, it's Gerry Gabrielse.
Much better articles available here, here, and here.
All I'm saying is that at the speeds their talking about, smashing a probe into a planet is likely to destroy a good chunk of what you're looking at. Do the math for a 2-ton object hitting something at .9c.
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
"A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
I think I read that matter and antimatter, while being equal, are not. In our universe, it takes more animatter to destroy matter.
This is incorrect. Matter and antimatter annihilate 1:1. This is due to conservation rules - most of the quantum numbers have to sum to zero for annihilation to occur (positive and negative charge cancel, positive and negative lepton or baryon numbers have to cancel, etc.).
What you're probably thinking of is the asymmetry in matter and antimatter _production_. Certain reactions tend to produce matter more often than antimatter (which is why there's any matter in the universe at all).