Mercury's magnetic field -- nipped in the bud

Mercury's magnetic field -- nipped in the bud
Focus on Mercury: The Messenger space probe - which took this image - has confirmed that the innermost planet has a magnetic field 150 times weaker than that of Earth. Researchers have now found an explanation for this. © NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

( -- Mercury, the smallest of the eight planets with a diameter of 4900 kilometres and the closest to the Sun, looks more like the Moon than the Earth from the outside. It is the only rocky planet that has a global magnetic field like Earth. But why is its magnetic field so much weaker than Earth’s? Scientists at the Technische Universität Braunschweig and the Max Planck Institute for Solar System Research have now presented a new explanation: the solar wind counteracts Mercury’s internal dynamo and thus weakens its magnetic field.

Planetary magnetic fields are generated by flows in the hot, liquid iron cores of the . Measurements made by Mariner 10 in 1974/75 showed that Mercury also has a magnetic field. According to the standard models, the dynamo effect in its metal core should generate similar field strengths to those on . Mercury’s magnetic field is 150 times weaker than that of our planet, however. This has recently been confirmed by the Nasa space probe Messenger.

How can the large discrepancy in the field strength be explained? This question has now been answered by a group headed by Karl-Heinz Glassmeier at the Technische Universität Braunschweig. The solar wind – a constant stream of charged particles – plays a significant role. At an average distance from the Sun of only 58 million kilometres – around one third of the distance of the Earth – Mercury is much more exposed to these particles.

“We must keep in mind that Mercury stongly interacts with the surrounding solar wind,” says Daniel Heyner, lead author of the article published in Science and doctoral student at the International Max Planck Research School (IMPRS) in Katlenburg-Lindau. This interaction drives strong electrical currents in the magnetosphere of the planet, whose magnetic fields counteract the internal dynamo effect.

The team’s new computer models show that a dynamo with this type of feedback is actually possible. “These types of simulation of the dynamo process are the only possibility to sort of look into the iron core and to predict the strength and structure of the magnetic field,” says Johannes Wicht from the Max Planck Institute for Solar System Research, whose model made a significant contribution to the study. The results show unambiguously that the feedback ultimately causes the weak magnetic field. “The dynamo process in Mercury’s interior is almost nipped in the bud by the interaction,” explains Glassmeier.

The researchers at the TU Braunschweig and the Max Planck Institute for Research are eagerly awaiting the next magnetic field measurements from the Messenger space probe and the observations of the two satellites of the European-Japanese mission BepiColombo. The mission will carry an instrument developed by the TU Braunschweig. Starting in 2020 the researchers want to measure ’s with great precision. The new data should allow the confirmation of this fascinating new idea of a dynamo weakened by the .

Explore further

MESSENGER data paints new picture of Mercury's magnetic field

More information: Daniel Heyner, Johannes Wicht, Natalia Gómez-Pérez, Dieter Schmitt, Hans-Ulrich Auster, Karl-Heinz Glassmeier, Evidence from Numerical Experiments for a Feedback Dynamo Generating Mercury’s Magnetic Field, Science, 23 December 2011. DOI: 10.1126/science.1207290
Journal information: Science

Citation: Mercury's magnetic field -- nipped in the bud (2011, December 23) retrieved 26 August 2019 from
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Dec 23, 2011
The teams new computer models show that a dynamo with this type of feedback is actually possible

Like I said a month or so ago, they'll have to come up with an incredible adhoc scenario to fix the currently observed +-27% decrease in magnetic field strength [compared to the last Mariner observation]. The simulation model unfortunately doesn't fix anything - it's simply an adhoc assumption to get out of a very tight spot. Who, or more appropriately, what is going to actually go there to confirm that the model works as claimed?
Oh, I see! Let's postpone the death-knell of internal dynamo theory till after 2020 by waiting out info from ANOTHER 2 satellites, BepiColombo. This will give the evolutionists time for their critics to perhaps pass on and forget the whole thing.
According to the standard models, the dynamo effect in its metal core should generate similar field strengths to those on Earth.
BUT it doesn't. A major problem for the dynamo theory is very slow rotation.

Dec 23, 2011
I suggest that the real reason for the weak magnetic field is the fact that there is NO internal dynamo. The field is simply the results of natural response decay after the planet was created.
Of course this suggestion flies in the face of the evolutionary adherent because it means that the planet couldn't be billions of years old, only a few thousand, otherwise the field would have decayed completely a long time ago.
So, faced with such a devastating possibility, the evolutionary adherents are forced to come up with the simulation model explanation involving solar wind.
They thereby gain time to continue earning their salaries before there is a final death to the theory. OK, that might be a bit harsh.

Dec 23, 2011
The other thing to consider is that even if the solar wind theory has any merit, why is there an approximately 27% decrease in strength of the magnetic field? Surely, it should be cancelled out as a common factor.
One could of course then argue that the previous estimate was way off beam - and no one could argue otherwise. Or else that the solar wind picked up strongly and now has a greater effect. Who could confirm that?
All in all, plenty of space for an out. Slippery as an eel.

Dec 23, 2011
"The other thing to consider" is that maybe you don't understand the science. This has nothing to do with evolution so stop ranting. Misrepresenting the science and creating ridiculous straw man arguments to rail against may make you look smart in your church, but here, where plenty of people actually understand the science, you just look like a stupid ignoramus.
You are not evangelising. You are not swaying minds. You are not challenging paradigms. You are not a martyr. You are spouting practically verbatim the bullcrap they write in Answers in Genesis and the ilk (I know, I'm a subscriber) and making yourself look ridiculous. I haven't seen a single post of yours where you haven't been shot down in flames. Stop wasting our bandwidth.

Dec 23, 2011

I signed up just to say that was very well said. It's been a long time since I've seen an intelligent response to a religious troll.

Well done sir!

Dec 23, 2011

Thread and website won

Dec 23, 2011
don't bother, Kevin is in his own world. i've seen him respond maybe, and i mean Maybe once to post that follows his. he's a tool in the strictest definition.

This has nothing to do with evolution so stop ranting.

however this made me smile, because you are 100% correct. hence adding substance to the Kevin is a tool hypothesis.

all i want for Christmas is for Kevin to find a new science site to troll and spout young earth nonsense. I'll pray even, if thats what it takes...

Dec 23, 2011
So in less words, the puny magnetic field of Mercury can take being blasted at close range by a sun many thousands of times its size? I could have guessed that and saved millions of dollars in research :)

Dec 23, 2011
J.E.P. Connerney of Goddard Space Flight Center and N. F. Ness of the University of Delaware noted in "Mercury's Magnetic Field and Interior" ( http://www.uapres...Ch15.pdf ), chapter 15 from the book Mercury, edited by Faith Vilas, Clark R. Chapman, and Mildred Shapley Matthews, 1989, about the original Mariner data: "Estimates of the dipole obtained from bow shock and/or magnetopause positions (only) range from approximately 200 nT-Rm^3 (Russell 1977) to approximately 400 nT-Rm^3 (Slavin and Holzer 1979b)." They "demonstrate that the lack of agreement among models is due to fundamental limitations imposed by the spatial distribution of available observations." Thus the scientific community has been unable to constrain the Mariner-derived dipole moment within a factor of 2, and yet kevinrtrs is somehow able to detect a decline of precisely 27% between that and the Messenger data? Not possible.

Dec 23, 2011
No no no. We don't want Kevin to go away. If it weren't for cranks like him, many of us wouldn't be learning from the actually well reasoned and informative responses. The cranks are what make this site worth our time, much unlike the published content with gems of such great scientific insight like:
The dynamo process in Mercurys interior is almost nipped in the bud by the interaction, explains Nob Odyc Ares, Phd.

Merry Christmas, kevinrtrs!! :)

Dec 23, 2011
1. Planetary magnetic fields are generated by flows in the hot, liquid iron cores of the planets.

2. Mercury stongly interacts with the surrounding solar wind

Statement #1 is a false assumption.

Statement #2 means Mercury's and the Sun's magnetic field's are coupled.

That is not surprising, since the enormous magnetic field of the Sun's pulsar core induced the magnetic fields in iron-rich cores of planets as they formed near the Sun.

Despite false claims by Al Gore, the UN's IPCC and world leaders that the Sun is Earth's constant source of heat [And man-made CO2 causes global warming], . . .

Solar cycles are cycles of magnetic fields that become visible as sunspots.

Magnetic fields of the Sun and the planets are highly variable.


As noted in the first posting on

Al Gore has no control over the Sun!


Dec 23, 2011
How is one person able to post three times, all at 0700 hrs EST and not get stopped by the site's flood protection. Also, we need a bit more of us to flag the abject commercialism from folks that just create an account and immediately post....never to heard from again! Under that false name anyway.

Dec 24, 2011
Reported abuse for the spam (including Oliver)
Well done Robo ;)

Dec 24, 2011
Kevinrtrs is absolutely correct.

I mean this is such a simple bit of "Oh Duh" maths, scaling and other correlative dissertations - that even I was able to get it all correct to within about 5% on the back of a restaurant napkin.

Dec 24, 2011
The only thing that worries me about nowadays advanced simulations in general is that it just so tempting to start from an assumption and then write code around it that gives the expected answer, sure my gut feeling says that mercury being close to the sun should significantly interact with the solar wind, but is it the only reason? and what about that simulation made by string theorists of a big bang in ten dimensions, sure that simulation fits their string theory but one could write a simulation consistent with a moon made of swiss cheese.

Dec 24, 2011
Maybe Kev doesn't realize that if god existed, he'd probably want us to be logical and not believe in him without proof.


Dec 24, 2011
This has nothing to do with evolution so stop ranting.

Actually, it has EVERYTHING to do with evolution. Please go read up how every observations and description of cosmology seems to include the word "evolution" these days.
Besides which, looked at in totality, those who do not believe in a Creator has no other means to explain how everything that exists came to be. The only way you can describe it is "It started with the big bang and then EVOLVED into stars, galaxies, planets and organic life forms."
So, please be a little more circumspect before shooting from the hip next time.
Further - I think your response simply brushes over the logic being applied by the researchers. In their eagerness to explain the minute magnetic field, they've blindsided people from the fact that the field strength is decreasing rapidly, to the extend that it could not in any way have existed for billions of years. In your eargernes to lambast my God, perhaps you choose to overlook this FACT too?

Dec 24, 2011
Thus the scientific community has been unable to constrain the Mariner-derived dipole moment within a factor of 2, and yet kevinrtrs is somehow able to detect a decline of precisely 27% between that and the Messenger data? Not possible.

Firstly, I wrote "approximately" and also showed elsewhere that the Mariner result was an estimate. In addition, I've covered exactly the excuse that the Mariner results were incorrect in one of the posts above.
Now, to find out where I get the approx. 27% decline from, please go read the papers by the people in charge of studying the magnetic field and read carefully what THEY say regarding the decrease. That's where I got it from. Enjoy!

Dec 24, 2011
Maybe Kev doesn't realize that if god existed, he'd probably want us to be logical and not believe in him without proof.

Actually, God provided exactly for such thinking. In the book of Romans, in the first chapter you'll find that He has indeed provided mankind with all kinds of indications of His existence and therefore mankind is without excuse in rejecting Him.
One such indication is exactly that the magnetic field of Mercury could not have lasted more than 100k years. The fact that mankind has now begun to measure it and found that it doesn't fit in with the evolutionary theory should be a great nudge in the ribs that perhaps there is a God. But since one can make up any old excuse that simply postpones a final answer[as in the article], one can go on deceiving oneself till it's too late to turn to the Creator for salvation.
To the Moderators: sorry, this statement deserves such a response.

Dec 24, 2011
Well Kev, no matter how hard I'd like to believe the whole shebang, I can't. No matter how hard I try, I can't pretend on the inside. If anything I'm agnostic in all my beliefs.

If it's all true, great !! If it's not, great !! Either way it makes no difference to me because I'm focused on _this_ life, the one I'm currently living, it's a blast.

~ and If I do end up in hell, roommates with Gilbert Gottfried, I won't complain because I'm not picky.

What's that old saying ? " To thine own self be true "

Dec 24, 2011 can go on deceiving oneself till it's too late to turn to the Creator for salvation.
That's great. Hey kevinrtrs did you know that every time you put your hands together in prayer, you are actually signaling your fellow believers you want to give them fellatio? You probably do, being you're so smart you naughty xtian.

Dec 24, 2011
You are beyond parody. You just demonstrated that you literally don't even understand the meaning of the English word "evolution" let alone the scientific concept that uses that name.
By the way, the book of Romans was written by a 1st century tentmaker from one of the empires less educated provinces. It doesn't really present evidence for anything except your own unthinking credulity.

And I'll keep shooting from the hip as long as long as you keep bringing a knife - scratch that, a damp sponge - to a gunfight.

Dec 25, 2011
Kevin, you must be referring to the ICR article by Brian Thomas where he says (referring to the Anderson et al 2008 paper in Science about the data from the first Messenger flyby) "[t]he Science authors wrote that the field strength for Mercury is "~27% lower in magnitude than the centered-dipole estimate implied by the polar Mariner 10 flyby." This confirms that Mercury's magnetic field is rapidly diminishing, which in turn confirms that the field must only be thousands of years old just as the creation model predicted."

It is important to note that Mariner magnetic field data came from two flybys, the first one (labeled I) approximately along the equator and the other one (labeled III) whose closest approach occurred at a latitude of 68 degrees North. Numerous scientists have modeled the Mercurian magnetic field using the data from I only, III only, or a combination thereof.

Dec 25, 2011
Subsequent to the Anderson et al 2008 paper, much higher quality data was obtained not from a flyby but from multiple orbits by the Messenger craft. Anderson et al 2011 ( http://www.scienc...abstract ) found that, unlike assumed in many of the previous models (Ness 1979), the dipole moment is significantly offset - to the North - from Mercury's center, and is thus not a centered dipole. The dipole moment is only 195 plus or minus 10 nT-Rm^3. Brian Thomas's statement is thus completely wrong. One can not compare the current field strength to an old one calculated using an incorrect model.

Dec 25, 2011
If we try to find a Mariner study using methods closest to this paper's ("A magnetopause and tail-current model" in conjunction with dipole and multipole moments calculated using "observations north of 30°N"), we alight upon the Jackson and Beard 1977 paper, which amongst other models supplied one using III-only data with a magnotopause and magnetotail, and reporting a dipole moment of 200 nT-Rm^3 (with quadrupole moment of 95 nT-Rm^3 -- offset dipoles have large quadrupole moments). Within the margin of error, the Mercury dipole moment has remained constant between the Mariner flybys and the Messenger orbits.

That Brian Thomas got this wrong is not surprising. He has an M.S in biotechnology, not physics or planetary science, and his article was a blog, not a paper in a peer-reviewed journal. You're going to have to check your sources a whole lot better, Kevin, before you'll be taken seriously.

Dec 28, 2011
The range is even bigger than I mentioned. Models of the field derived from spherical harmonic analysis give centered dipole moments ranging from 136 to 350 nT-Rm^3. Combine this with the models derived by using the magnetopause or bowshock positions (200-400) and we have a range of estimates from 136 to 400 nT-Rm^3.

Jan 03, 2012
Barakn - thanks for taking the time to research and summarize this data. Knowledge and reason always trump blind faith.

What is it the Bible says? "And the light shineth in darkness; and the darkness comprehended it not." (John 1:5) Mmm, now that's some good irony.

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