James Hrynyshyn is a freelance science journalist based in western North Carolina, where he tries to put degrees in marine biology and journalism to good use.
Every now and then, a science story comes along that reminds me just how full of awe and wonder the real world is. This particular story is a few weeks old, but it didn't seem to generate a lot of attention when it came out, so I will.
Astronomers and physicists using the Cornell-managed Arecibo Telescope in Puerto Rico have discovered radio interpulses from the Crab Nebula pulsar that feature never-before-seen radio emission spectra. This leads scientists to speculate this could be the first cosmic object with a third magnetic pole.
A third pole? How weird and wonderful. Such musings contradict everything I was ever taught in high school, and no one ever bothered to mention anything like that during my university advanced physics course, either. Read on:
"We never see the strange frequency structure in the main pulse and we never see the really short blasts in the interpulse," said Tim Hankins, acting director of the Arecibo Observatory and a co-investigator on this research. "We fully expected the main pulse and interpulse to be spectrally identical, but what we found is that they are very different. This is the first time seeing this in a pulsar."My grasp of the physics of magnetism isn't sufficiently sophisticated to understand just how an object can have more than two magnetic poles. Kind of throws you for a loop, doesn't it? The astronomers themselves admit to being "perplexed."Hankins, who also is an emeritus professor of physics at New Mexico Tech in Socorro, N.M., will present a poster, "Radio Emission Signatures in the High Frequency Interpulse of the Crab Pulsar," which he made with Jean Eilek, New Mexico Tech professor of physics, on Jan. 8, 2007, at the American Astronomical Society (AAS) convention in Seattle.
"This is a cool result," said Eilek. "The fact that the 'left hand' and the 'right hand' of the pulsar - or the north and south magnetic poles - don't know what each other is doing, is very striking. It knocks just about every existing theory of pulsar radio emission for a loop."
Because pulses from north and south poles should be identical, Eilek thinks this strange radio emission might be coming from another part of the pulsar. She speculates: "Maybe we've discovered an unknown, unexpected 'third magnetic pole' somewhere else in the star."
Sir Arthur Eddington was right. "Not only is the universe stranger than we imagine, it is stranger than we can imagine." But wait, there's more:
In the case of the Crab Nebula pulsar, located in the constellation Taurus, some 6,300 light years from Earth, the numbers boggle the mind: Plasma clouds in the pulsar's atmosphere send out the radio emission blasts in times as short as four-tenths of a nanosecond. This plasma cloud is smaller than a soccer ball. During their short lifetimes, their blasts of radio emission can be as powerful as 10 percent of the power of our sun.
It's this kind of discovery that puts the lie to the idea that we need to look beyond the natural universe for the spiritual inspiration. Why bother inventing paranormal or supernatural scenarios when reailty is so amazing?
Comments
Three magnetic poles would indeed be weird, since you're not supposed to be able to get single magnetic monopoles, only dipoles. A quadropolar magnetic field (i.e the pulsar has two 'north' and two 'south' poles) would perhaps be more likely.
Posted by: Chris Rowan | March 2, 2007 7:58 AM
I agree with Chris Rowan.
Of course, hyperspherical bodies can rotate around two planes simultaneously. One might say that a hyperstar or hyperplanet has a North and South pole on an axis perpendicular to one plane of rotation, and an East and West pole on an axis perpendicular to the other plane of rotation.
But this story cited is not about 4-dimensional gravity and hyperplanets. I'm just thinking like a Science Fiction writer, and remembering some conversations I had with math Professor/Physics professor inventor Dr. Tim Poston, who likes to imagine the details of life on 4-D hyperplanets.
Beyond cool, into mindblowing.
Posted by: Jonathan Vos Post | March 2, 2007 6:46 PM
Yes, hyperspherical bodies can rotate around two planes simultaneously, but the 'axis' of each rotation is the other plane, not a line. So instead of a pair or two of poles, you get a turning equator in each plane, each with its own fixed day length. (In between, days are complicated.)
Back on the original story, poles (even monopoles) should be North or South, by the nature of the magnetic field between them. The quotes mainly suggest that (a) the researchers think there is a more fancy structure than usual, complicating the usual coupling between two poles, and (b) the un-named NewsWise reporter did not get a clear grip on what they were saying. A link to their actual report, if and when it goes on line, would be nice to see.
Posted by: Tim Poston![[TypeKey Profile Page]](http://scienceblogs.com/islandofdoubt/nav-commenters.gif)
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March 2, 2007 7:27 PM
Well, assuming no electrical conductance outside of the pulsar surface, the field has to obey Maxwells equations, you get a bunch of vector fields, the lowest order is the familar dipole, whos strength falls off as 1/R**3, there are potentially three of these possible (up/down east/west north/south). Then you add in the next order terms
(which fall-off by 1/r**4 -or is it maybe 1/r**5), and these will be higher order spherical harmonics. In any case you have available of infinite series of these babies, and can match essentially any field coming off the surface. If you get far enough from the source, and the dipole term is non-zero it will eventually dominate, and you'll see the familar pattern of a bar magnet. At the surface the total flux of North versus South must balance out (no mag monopoles).
If the pulsar is active, it may be surrounded by plasma, and currents within this plasma are an additional complicating source of the magnetic field. In any case complicated field patterns don't violate the laws of physics -but they are unexpected.
Posted by: bigTom | March 2, 2007 8:29 PM