The interstellar lighthouse

It's funny the questions you don't think to ask.  You find out something, accept it without any objections, and only later -- sometimes much later -- you stop and go, "Okay, hang on a moment."

That happened to me just yesterday, about a topic most of us don't ponder much, and that's the peculiar astronomical object called a neutron star.  It was on my mind not by random chance -- even I don't just sit around and say, "Hmm, how about those neutron stars, anyway?" -- but because of some interesting research (about which I'll tell you in a bit).

I first learned about these odd beasts when I took a class called Introduction to Astronomy at the University of Louisiana.  The professor, Dr. Whitmire, explained them basically as follows.

Stars are stable when there's a balance between two forces -- the outward pressure from the heat generated in the core, and the inward pull because of the gravity exerted by the star's mass.  During most of a star's life, those two are in equilibrium, but when the core exhausts its fuel, the first force diminishes and the star begins to collapse.  With small stars like the Sun, the collapse continues until the mutual repulsion of the atoms' electrons becomes a sufficient force to halt it from shrinking further.  This generates a white dwarf.

In a star between 10 and 29 times the mass of the Sun, however, the mutual electric repulsion isn't strong enough to stop the collapse.  The matter of the star continues to fall inward until it's only about ten kilometers across -- a star shrunk to the diameter of a small city.  This causes some pretty strange conditions.  The matter in the star becomes unimaginably dense; a teaspoon of it would have about the same mass as a mountain.  The pressure forces the electrons into the nuclei of the atoms, crushing out all the space, so that what you have is a giant electrically-neutral ball -- effectively, an enormous atomic nucleus made of an unimaginably huge number of neutrons.

The first neutron star ever discovered, at the center of the Crab Nebula [Image is in the Public Domain, courtesy of NASA/JPL]

The immense gravitational pull means that the surface of a neutron star is the smoothest surface known; any irregularities would be flattened out of existence.  (It's worth mentioning that even the Earth is way smoother than most people realize.  The distance between the top of Mount Everest and the bottom of the Marianas Trench is less, as compared to its size, than the topographic relief in a typical scratch on a billiard ball.)

So far, so good.  But it was the next thing Dr. Whitmire told us that should have made me pull up short, and didn't until now -- over forty years later.  He said that as a neutron star forms, the inward collapse makes its rotational speed increase, just like a spinning figure skater as she pulls in her arms.  Because of the Conservation of Angular Momentum, this bumps up the rotation of a neutron star to something on the order of making a complete rotation thirty times per second.  A point on the surface of a typical neutron star is moving at a linear speed of about one-third of the speed of light.

Further, because neutron stars have a phenomenally large magnetic field, this creates two magnetic "funnels" on opposite sides of the star that spew out jets of electromagnetic radiation.  And if these jets aren't aligned with the star's spin axis, they whirl around like the beams of a lighthouse.  A neutron star that does this, and appears to flash on and off like a strobe light, is called a pulsar.

This was the point when the red flags should have started waving, especially since I majored in physics and had taken a class called "Electromagnetism."  One of the first things we learned is that Scottish physicist James Clerk Maxwell discovered that magnetic fields are generated when charged particles move.  So how can a neutron star -- composed of electrically-neutral particles -- have any magnetic field at all, much less one so huge?  (The magnetic field of a typical neutron star is on the order of ten million Tesla; by comparison, one of the largest magnetic fields ever generated in the laboratory is a paltry sixteen Tesla, but was still enough to levitate a frog.)

The answer is a matter of conjecture.  One possibility is that even though a neutron star is neutral overall, there is some separation of charges within the star's interior, so the whirling of the star still creates a magnetic field.  Another possibility is that since neutrons themselves are composed of three quarks, and those quarks are charged, neutrons still have a magnetic moment, and the alignment of these magnetic moments coupled with the star's rotation is sufficient to give it an overall enormous magnetic field.  (If you want to read more about the answer to this curious question, the site Medium did a nice overview of it a while back.)

So it turns out that neutron stars aren't the simple things they appeared to be at first.  Not that this is much of a surprise; a recurring theme here at Skeptophilia is that nature always seems to turn out to be more complicated than we expected.  What brought this up in the first place was yet another anomalous observation about neutron stars, described in a series of papers I ran across in Astrophysical Journal Letters.  The conventional wisdom was that a neutron star's magnetic field would be oriented along an axis (which, as noted above, may not coincide perfectly with the star's spin axis).  This means that it would behave a bit like an ordinary magnet, with a north pole and a south pole on geometrically opposite sides.

That's what astronomers thought, until they found a pulsar with the euphonious name J0030+0451, 1,100 light years away in the constellation of Pisces.  Using the x-ray jets from the pulsar -- which should be aligned with its magnetic field -- they mapped the field itself, and found something extremely strange.

Instead of two jets, aligned with the poles of the magnetic field, J0030+0451 has three -- and they're all in the southern hemisphere.  One is (unsurprisingly) at the southern magnetic pole, but the other two are elongated crescents at about sixty degrees south latitude.

To say this is surprising is an understatement, and the astronomers are still struggling to explain it.

"From its perch on the space station, NICER [the Neutron star Interior Composition Explorer] is revolutionizing our understanding of pulsars," said Paul Hertz, astrophysics division director at NASA Headquarters in Washington.  "Pulsars were discovered more than fifty years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth."

It appears that we still have a way to go to fully explain how they work.  But that's how it is with the entire universe, you know?  No matter where we look, we're confronted by mysteries.  Fortunately, we have a tool that has proven over and over to be the best way of finding answers -- the collection of protocols we call the scientific method.  I have no doubt that the astrophysicists will eventually explain the odd magnetic properties of pulsars.  But the way things go, all that'll do is open up more fascinating questions -- which is why I've said many times that if you're interested in science, you'll never run out of things to learn.

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Strange attractor

I've always found the concept of the Strong Anthropic Principle wryly amusing.

The idea here is that something (usually a benevolent deity) fine-tuned the universe in just such a way to be hospitable for us -- for having forces perfectly balanced to hold matter together without causing a runaway collapse, for having gravitational pull strong enough to form stars and planets, for having electromagnetic forces of the right magnitude to generate the chemical reactions that ultimately led to organic molecules and life, and so on.

To me, this argument ignores two awkward facts.  First, of course our universe has exactly the right characteristics to generate and support life; if it didn't, we wouldn't be here to consider the question.  (This is called the "Weak Anthropic Principle," for obvious reasons.)  Second, though -- the Strong Anthropic Principle conveniently avoids the fact that a large percentage of the Earth, and damn near 100% of the universe as a whole, is completely and unequivocally hostile to us, and probably to just about any living thing out there.

It's one of those hostile bits that got me thinking about the whole issue today, because astronomers just last week observed a phenomenon called a fast radio burst in our own galaxy -- a mere thirty thousand light years away -- and the thing that produces it is not only bizarre in the extreme, but is something that we're very, very lucky not to be any closer to.

The beast that produces this is called a magnetar, and appears to be a rapidly-spinning neutron star, with a mass of two to three times that of the Sun but compressed into a sphere only about twenty kilometers in diameter.  This means that the surface gravitational attraction is astronomical (*rimshot*).  Any irregularities in the topography would be crushed, giving it a smooth surface with a relief less than that of a brand-new billiard ball.

The most bizarre thing about magnetars, however, is the immense magnetic field that gives them their name.  Your typical magnetar has an average magnetic field flux density of ten billion Teslas -- on the order of a quadrillion times the field strength of the Earth.  This is why they are, to put it mildly, really fucking dangerous.  The article in Astronomy about last week's discovery explained it graphically (if perhaps using slightly more genteel language):

The magnetic field of a magnetar is about a hundred million times stronger than any human-made magnet.  That’s strong enough that a magnetar would horrifically kill you if you got within about 620 miles (1,000 km) of it.  There, its insanely strong magnetic field would pluck electrons from your body’s atoms, essentially dissolving you.

This brought up a question in my mind, though; magnetic fields of any kind are made by moving electrical charges -- so how can a neutron star (made, as one would guess, entirely of neutrons) have any magnetic field at all, much less an insanely strong one?  Turns out I'm not the only one to ask this question, as I found out when I did some digging and stumbled on the Q-and-A page belonging to Cole Miller, Professor of Astronomy at the University of Maryland.  Miller says the reason is that not all of the particles in a neutron star are neutrons.  While the structure as a whole is electrically neutral, about ten percent of the total mass is made up of electrons and protons that are free to move.  Take those charged particles and whirl them around hundreds of times per second, and you have a magnetic field that is not only insanely strong, but really fucking dangerous.

This all comes up because of last week's observation of a thirty-millisecond-long fast radio burst coming from within our galaxy.  All the others that have been detected were in other galaxies, and the distances involved (not to mention how sporadic they are, and how quickly they're over) make them difficult to explain.  But this comparatively nearby one gave us a load of new information -- especially when a second burst came from the same magnetar a few days later.

[Image licensed under the Creative Commons ESO/L. Calçada, Artist’s impression of the magnetar in the extraordinary star cluster Westerlund 1, CC BY 4.0]

As this observation was only made last week, astronomers and astrophysicists are still trying to explain it, including odd features such as its relative faintness.  As compared to bursts from other galaxies this one was a thousand times less luminous.  Why is still a matter of conjecture.  Is it because bursts this weak occur in other galaxies, but from this distance would be undetectable?  Is it because the distant galaxies are much younger (remember, looking out in space is equivalent to looking back in time), so stronger bursts only happen early in a galaxy's evolution?  At this point, we don't know.  As Yvette Cendes, author of the Astronomy article, put it:

It is far too early to draw a firm conclusion about whether this relatively faint FRB-like signal is the first example of a galactic fast radio burst — making it the smoking gun to unlocking the entire FRB mystery.  And there are also still many preliminary questions left to answer.  For example, how often do these fainter bursts happen?  Are they beamed so not all radiation is equally bright in all directions?  Do they fall on a spectrum of FRBs with varying intensities, or are they something entirely new?  And how are the X-ray data connected?

As usual with science, the more we know, the more questions we have.

In any case, here we have a phenomenon that's cool to observe, but that you wouldn't want to be at all close to.  Not only do we have the magnetic field to worry about, but the burst itself is so energetic that anything nearby would get flash-fried.

So "the universe is fine-tuned to be congenial to us" only works if you add, "... except for the 99.9% of it that is actively trying to kill us."  Not that this makes it any less magnificent, but it does make you feel a little... tiny, doesn't it?  Probably a good thing.  Humans do stupid stuff when they start thinking they're the be-all-end-all.

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This week's Skeptophilia book recommendation is about a phenomenal achievement; the breathtaking mission New Horizons that gave us our first close-up views of the distant, frozen world of Pluto.

In Alan Stern and David Grinspoon's Chasing New Horizons: Inside the Epic First Mission to Pluto, you follow the lives of the men and women who made this achievement possible, flying nearly five billion kilometers to something that can only be called pinpoint accuracy, then zinging by its target at fifty thousand kilometers per hour while sending back 6.25 gigabytes of data and images to NASA.

The spacecraft still isn't done -- it's currently soaring outward into the Oort Cloud, the vast, diffuse cloud of comets and asteroids that surrounds our Solar System.  What it will see out there and send back to us here on Earth can only be imagined.

The story of how this was accomplished makes for fascinating reading.   If you are interested in astronomy, it's a must-read.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Animal magnetism

In my introductory neuroscience class, I always began the unit on our sensory systems by asking students how many senses they think we have.

The standard answer, of course, is "five."  There were always a few wishful thinkers who like the idea of psychic abilities and answered six.  They were uniformly blown away when I told them that depending on how you count them, it's at least twenty.

Don't believe me?  There are three in the ears (hearing, proprioception/balance, and pressure equalization).  The tongue has separate, distinct chemoreceptors for at least five different taste categories -- sour, sweet, salty, bitter, and savory.  For convenience we'll call the sense of smell one, because we don't even know how many different kinds of olfactory receptors we have.  The eyes are not only responsible for image reception, but also perception of depth and adjustments for light intensity.  You've got six in your skin -- touch, pain, pressure, heat, cold, and stretch.  Your brain has chemical sensors that keep track of your blood pH and stimulate your breathing rate to speed up or slow down to accommodate (in general, breathing faster dumps carbon dioxide and makes your blood pH rise; slower breathing makes you retain carbon dioxide and drops your blood pH).  The kidneys have sensors not only for blood pH but for the salt/water balance, concentrating or diluting your urine to keep your blood's osmotic balance correct.

And those are just the most obvious ones.

In reality, your body is a finely-tuned environmental sensor, constantly detecting and making adjustments to your internal state to accommodate for the external conditions.  It works admirably well most of the time, even though there are some stimuli out there detectible by other animal species that we are completely unaware of.

The one that jumps to mind first is the range of light frequencies the eyes can detect.  We can only pick up a tiny slice of the entire electromagnetic spectrum, the familiar red-orange-yellow-green-blue-indigo-violet of the rainbow.  Many insects can see in the ultraviolet region, picking up light waves completely invisible to us; this is why a good many flowers that seem to be a single color to us have wild patterns if photographed with a UV-sensitive camera.  Mosquitoes can pick up infrared light, meaning they see the world through heat-sensing goggles -- with the unfortunate result that they can find us with ease in the pitch dark.  (They can also smell us, apparently, possibly explaining why some people are so attractive to the little bastards.)

How a bee sees a flower of Potentilla reptans that looks solid yellow to us [Image licensed under the Creative Commons Wiedehopf20, Flower in UV light Potentilla reptans, CC BY-SA 4.0]

Sharks can pick up shifts in the underwater electric field, one way they find their prey -- muscle contractions run on electrical signals.  So, oddly enough, can platypuses, using electric sensors in their weird rubbery bill.  Many species of migratory birds are sensitive to magnetic fields, using magnetite crystals in their brains as a natural compass -- and, some scientists think, not only using them to figure out which direction is north, but using the declination (angle it tips up or down with respect to horizontal) to figure out the latitude, as the Earth's magnetic field lines become more and more vertical the closer you get to the poles.

This last one is a sense humans might actually share.  There have been anecdotal accounts for years of some people being sensitive to magnetic fields, but there hasn't been any hard evidence of it.  Now, a paper in eNeuro describes an experiment that shows the human brain has sensitivity to magnetic fields -- even if the owner of the brain may not be aware of it on a conscious level.

In "Transduction of the Geomagnetic Field as Evidenced from alpha-Band Activity in the Human Brain," by a team led by Connie Wang of the California Institute of Technology, we read about a clever set-up to see what was going on in people's heads when they were subjected to a fluctuating magnetic field.

The thought was, if there is anything at all to the anecdote, it should be detectible by an electroencephalogram.  "Our approach was to focus on brainwave activity alone," said study co-author Joseph Kirschvink (also of CIT) in an interview with Gizmodo.  "If the brain is not responding to the magnetic field, then there is no way that the magnetic field can influence someone’s behavior.  The brain must first perceive something in order to act on it—there is no such thing as ‘extra-sensory perception.’  What we have shown is this is a proper sensory system in humans, just like it is in many animals."

Test subjects were placed in a Faraday cage, a web of conductive material that blocks electromagnetic fields, to shut out anything coming from the Earth's magnetism.  Then, an array of Merritt coils were activated to alter the magnetic field within the cage.  The subjects were asked if they detected anything -- and at the same time, the EEG machine kept track of what was going on inside their skulls.

The results are fascinating.  The effect of the magnetic field shifts on the alpha waves was dramatic; you don't need a class in reading EEGs to see it.  What was equally interesting is that none of the test subjects reported being aware of any changes.  So even though there's a dramatic change in the brain waves, whatever effect that's having, if any, is happening on a completely subconscious level.

But it does mean the anecdotal stories about people's sensitivity to magnetic fields have at least a possible explanation.  It still doesn't mean those anecdotes are reliable -- that would take test subjects who were able to report a detectible change when the magnetic field shifted the wave pattern in their brains -- but it's a step in the right direction.

"Magnetoreception is a normal sensory system in animals, just like vision, hearing, touch, taste, smell, gravity, temperature, and many others," Kirschvink said.  "All of these systems have specific cells that detect the photon, sound wave, or whatever, and send signals from them to the brain, as does a microphone or video camera connected to a computer.  But without the software in the computer, the microphone or video camera will not work.  We are saying that human neurophysiology evolved with a magnetometer—most likely based on magnetite—and the brain has extensive software to process the signals."

So this might be another one to add to the list of human senses, at least for some of us.  Whatever the results, it's certain that we're more finely-tuned to our environment than we realize -- and sensitive to stimuli to which we've always thought we were wholly insensate.

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This week's Skeptophilia book recommendation of the week is a classic -- Martin Gardner's wonderful Did Adam and Eve Have Navels?

Gardner was a polymath of stupendous proportions, a mathematician, skeptic, and long-time writer of Scientific American's monthly feature "Mathematical Games."  He gained a wonderful reputation not only as a puzzle-maker but as a debunker of pseudoscience, and in this week's book he takes on some deserving targets -- numerology, UFOs, "alternative medicine," reflexology, and a host of others.

Gardner's prose is light, lucid, and often funny, but he skewers charlatans with the sharpness of a rapier.  His book is a must-read for anyone who wants to work toward a cure for gullibility -- a cure that is desperately needed these days.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

The interstellar lighthouse

It's funny the questions you don't think to ask.  You find out something, accept it without any objections, and only later -- sometimes much later -- you stop and go, "Wait a moment."

That happened to me just yesterday, about a topic most of us don't ponder much, and that's the peculiar astronomical object called a neutron star.  It was on my mind not by random chance -- even I don't just sit around and say, "Hmm, how about those neutron stars, anyway?" -- but because of some interesting new research (about which I'll tell you in a bit).

I first learned about these odd beasts when I took a class called Introduction to Astronomy at the University of Louisiana.  The professor, Dr. Whitmire, explained them basically as follows.

Stars are stable when there's a balance between two forces -- the outward pressure from the heat generated in the core, and the inward pull because of the gravity exerted by the star's mass.  During most of a star's life, those two are in equilibrium, but when the core exhausts its fuel, the first force diminishes and the star begins to collapse.  With small stars like the Sun, the collapse continues until the mutual repulsion of the atoms' electrons becomes a sufficient force to halt it from shrinking further.  This generates a white dwarf. 

In a star between 10 and 29 times the mass of the Sun, however, the mutual electric repulsion isn't strong enough to stop the collapse.  The matter of the star continues to fall inward until it's only about ten kilometers across -- a star shrunk to the diameter of a small city.  This causes some pretty strange conditions.  The matter in the star becomes unimaginably dense; a teaspoon of it would have about the same mass as a mountain.  The pressure forces the electrons into the nuclei of the atoms, crushing out all the space, so that what you have is a giant electrically-neutral ball -- effectively, an enormous atomic nucleus made of an unimaginably huge number of neutrons.

The first neutron star ever discovered, at the center of the Crab Nebula [Image is in the Public Domain, courtesy of NASA/JPL]

The immense gravitational pull means that the surface of a neutron star is the smoothest surface known; any irregularities would be flattened out of existence.  (It's worth mentioning that even the Earth is way smoother than most people realize.  The distance between the top of Mount Everest and the bottom of the Marianas Trench is less, as compared to its size, than the topographic relief in a typical scratch on a billiard ball.)

So far, so good.  But it was the next thing Dr. Whitmire told us that should have made me pull up short, and didn't until now -- forty years later.  He said that as a neutron star forms, the inward collapse makes its rotational speed increase, just like a spinning figure skater as she pulls in her arms.  Because of the Conservation of Angular Momentum, this bumps up the rotation of a neutron star to something on the order of making a complete rotation thirty times per second.  A point on the surface of a typical neutron star is moving at a linear speed of about one-third of the speed of light.

Further, because neutron stars have a phenomenally large magnetic field, this creates two magnetic "funnels" on opposite sides of the star that spew out jets of electromagnetic radiation.  And if these jets aren't aligned with the star's spin axis, they whirl around like the beams of a lighthouse.  A neutron star that does this, and appears to flash on and off like a strobe light, is called a pulsar.

This was the point when the red flags should have started waving, especially since I majored in physics and had taken a class called "Electromagnetism."  One of the first things we learned is that Scottish physicist James Clerk Maxwell discovered that magnetic fields are generated when charged particles move.  So how can a neutron star -- composed of electrically-neutral particles -- have any magnetic field at all, much less one so huge?  (The magnetic field of a typical neutron star is on the order of ten million Tesla; by comparison, one of the largest magnetic fields ever generated in the laboratory is a paltry sixteen Tesla, but was still enough to levitate a frog.)

The answer is a matter of conjecture.  One possibility is that even though a neutron star is neutral overall, there is some separation of charges within the star's interior, so the whirling of the star still creates a magnetic field.  Another possibility is that since neutrons themselves are composed of three quarks, and those quarks are charged, neutrons still have a magnetic moment, and the alignment of these magnetic moments coupled with the star's rotation is sufficient to give it an overall enormous magnetic field.  (If you want to read more about the answer to this curious question, the site Medium did a nice overview of it a while back.)

So it turns out that neutron stars aren't the simple things they appeared to be at first.  Not that this is much of a surprise -- seems like every time we answer one question in science, it generates three new ones.  What brought this up in the first place was yet another anomalous observation about neutron stars, described in a series of papers this past week in Astrophysical Journal Letters.  The conventional wisdom was that a neutron star's magnetic field would be oriented along an axis (which, as noted above, may not coincide perfectly with the star's spin axis).  This means that it would behave a bit like an ordinary magnet, with a north pole and a south pole on geometrically opposite sides.

That's what astronomers thought, until they found a pulsar with the euphonious name J0030+0451, 1,100 light years away in the constellation of Pisces.  Using the x-ray jets from the pulsar -- which should be aligned with its magnetic field -- they mapped the field itself, and found something extremely strange.

Instead of two jets, aligned with the poles of the magnetic field, J0030+0451 has three -- and they're all in the southern hemisphere.  One is (unsurprisingly) at the southern magnetic pole,  but the other two are elongated crescents at about sixty degrees south latitude.

To say this is surprising is an understatement, and the astronomers are still struggling to explain it.

"From its perch on the space station, NICER [the Neutron star Interior Composition Explorer] is revolutionizing our understanding of pulsars," said Paul Hertz, astrophysics division director at NASA Headquarters in Washington.  "Pulsars were discovered more than fifty years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth."

It appears that we still have a way to go to fully explain how they work.  But that's how it is with the entire universe, you know?  No matter where we look, we're confronted by mysteries.  Fortunately, we have a tool that has proven over and over to be the best way of finding answers -- the collection of protocols we call the scientific method.  I  have no doubt that the astrophysicists will eventually explain the odd magnetic properties of pulsars.  But the way things go, all that'll do is open up more fascinating questions -- which is why if you're interested in science, you'll never run out of things to learn.

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This week's Skeptophilia book recommendation is pure fun, and a perfect holiday gift for anyone you know who (1) is a science buff, and (2) has a sense of humor.  What If?, by Randall Munroe (creator of the brilliant comic strip xkcd) gives scientifically-sound answers to some very interesting hypothetical questions.  What if everyone aimed a laser pointer simultaneously at the same spot on the Moon?  Could you make a jetpack using a bunch of downward-pointing machine guns?  What would happen if everyone on the Earth jumped simultaneously?

Munroe's answers make for fascinating, and often hilarious, reading.  His scientific acumen, which shines through in xkcd, is on full display here, as is his sharp-edged and absurd sense of humor.  It's great reading for anyone who has sat up at night wondering... "what if?"

[Note:  if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Dirt magnets

New on the market for people with more money than sense, we have: magnetized balls that you put in with your laundry to clean your clothes better.

[image courtesy of the Wikimedia Commons]

Called the "Life Miracle® Magnetic Laundry System," the idea is that putting magnets in your washing machine will somehow suck dirt particles off the clothes.  Or something like that.  It's hard to tell, frankly, because most of their sales pitch sounds like this:

The concept behind the Life Miracle Laundry System is that you can achieve similar results using a chemical-free, completely renewable magnetic basis, without using non-renewable petrochemicals.  Magnetic force is one of the most powerful forces on earth. In fact, the earth itself is like a giant magnet with a north and south pole. It is an amazing source of natural energy.  Even the weak magnets on your refrigerator defy the force of gravity without batteries or being plugged into any power source.  They will stay on your refrigerator, doing work and holding up papers for decades with no external power source.  Where does all this natural power come from?  From the environment around us.  It is completely renewable and totally free.  We are simply harnessing that amazing force and focusing it in your home washing machine to affect the water.

Since the Earth has such a powerful magnetic field, it's kind of strange that our clothes get dirty in the first place.  If dirt particles were pulled away from your clothes by magnets, seems like all you'd have to do is walk around and the dirt would just fall off.  Or, in the case of really dirty clothes, give yourself a good rubdown with a bar magnet.

Be that as it may, they have a great scientific explanation of how it works:

At an atomic level, everything is affected by magnetics. All you need to do it try is for yourself and see the results with your own eyes.

So there you have it.  Atomic forces you can see with the naked eye!

Later on, though, they throw in a few caveats.  In the FAQs, in fact, we're given an answer to the question of whether the magnet balls will actually get our clothes clean and bright:

That depends on your definition of “clean” and “bright”.  When comparing the usage of the Magnetic Laundry System with laundry detergent, you need to factor in a few things...  We define clean as chemical-free, non-harmful to the wearer and non-toxic to the environment, in addition to being optically acceptable.  But only you, the user and owner of the product can determine that.

So apparently whether the magnets work to make your clothes clean depends on what you mean by "work."  

We also find out that the Magnetic Laundry System gives you best results when you also use detergent:

The Life Miracle Laundry System® is a laundry detergent alternative only. Just like when using laundry detergent, separate products used for other functions must be used separately, like spot stain treatments, and whitening bleach products.  These are separate from the Laundry System just as they are separate from detergent... [and] nothing whitens like chlorine bleach, but there are few chemicals that are more toxic for the environment and health.  Bleach is very harsh and damaging to you clothes as well.  That said, if you don’t mind the tradeoffs, you can still use diluted bleach with Life Miracle Laundry System® if you choose.

Then we're told that the magnet balls also don't kill microorganisms, either:

Laundry detergent is not used to kill microorganisms, and neither is the Laundry System, but the cleaning process itself washes away most bacteria.  However, hot water will kill most microorganisms in the water, and a little bleach will do the same (although bleach works best at high temperatures).  An extremely effective natural alternative: Numerous studies show that a straight 5 percent solution of vinegar—such as you can buy in the supermarket—kills 99% of bacteria, 82% of mold, and 80% of germs (viruses).

So you still have to use detergent, bleach, and hot water.  What exactly is it that the magnet balls do, then?

Um... well... they're all-natural!  And non-toxic!  And don't pollute the environment!  And never need to be replaced!

What more can you ask for?

Until today, I didn't realize that the placebo effect applied to doing your laundry, but apparently it does.  Who knew?

So anyway.  Here again we have a good case for why we should put more emphasis on teaching science.  Anyone who has taken an introductory high-school-level physics course would be able to explain why the only way magnets would clean your clothes is if they were covered with iron filings.  For getting anything else washed clean -- especially anything oily -- you need a surfactant.

I.e., detergent or soap.

On the other hand, if they could develop magnets that attract dog hair, I'd be all for it.  As long as the magnets were "chemical-free," of course.  Can't have any chemicals around, you know.  Those things are dangerous.