Why Earth's Magnetic Field Might Not Flip After All

Live Science ^ | April 30, 2018 03:35pm ET | Stephanie Pappas,

[BenLurkin]

In a study published in the journal Proceedings of the National Academy of Sciences today (April 30), researchers ... found that today's patterns don't resemble the two most extreme disruptions in the past 50,000 years, when the magnetic field nearly reversed. [7 Ways the Earth Changes in the Blink of an Eye]

Instead, the modern field appears similar to the field during two other periods — one 49,000 ago, and one 46,000 years ago — when the field wobbled but didn't flip-flop.

... Currently, magnetic north is very close to the North Pole, while magnetic south is near the South Pole. That's been the case for about 780,000 years — the last time the geomagnetic field underwent a complete reversal, with magnetic north and south swapping places. But the field has been weakening by about 5 percent per century since direct observations started in 1840, and indirect observations hint that this weakening might have been going on for at least 2,000 years, Maxwell Brown, who studies paleomagnetism at the University of Iceland, and his colleagues wrote in their new paper. A particularly weak area called the South Atlantic Anomaly, which stretches from South Africa to Chile, has been pinpointed as a potential ground zero for a global polarity reversal.

Brown and his colleagues wanted to compare today's conditions with the magnetic field of years past. They focused on two "excursions," which are major disruptions of the geomagnetic field that don't necessarily involve a global reversal of magnetic north and south. One, the Laschamp excursion, occurred about 41,000 years ago. During that excursion, the magnetic field was a complex muddle without a clear magnetic north and south. The other, the Mono Lake excursion, happened about 34,000 years ago and was marked by a very weak magnetic north and south.

[Sergio]

Question for those who know...

Not a gotcha or sarcasm, actual curiosity on my part.

A planet’s gravity is a function of the planet’s mass.

Whereas magnetic North and South is determined by magnetic fields created by our planet’s iron core in conjunction with the planet’s rotation.

So can I assume that on planets that do not have an iron core or better said, that do not have magnetic fields, that a compass would be useless?

I.E. a plant can have gravity without having a magnetic North/South. True or false?

Thanks in advance for any and all information provided.

[Magnum44]

The following may help:

We live on the "crust" which is the only truly 'solid' portion of the planet. The mantle and core are in various states of liquid under immense pressure and still moving. Contained within these are the ferrous metals that, with motion, create the magnetic field. The field is often modeled (simplified) as a large dipole magnate, but in fact it is better represented by in infinite number of smaller magnates that are constantly (though slowly) shifting.

Eventually, like in several billion years, the Earth may cool to the point where the mantle and core become solid and the magnetic field created may weaken or die. This is the current thinking of what happened to Mars.

[Magnum44]

a plant can have gravity without having a magnetic North/South. True or false?

True, see post 42

[Sergio]

Thanks Magnum44

That planets without a magnetic North/South could exist never occurred to me until reading this thread.

FR makes you smarter!

[DannyTN]

I’ve been working on reversing the earth’s rotation for a while now. There’s some things I want to do different when I was younger.

[editor-surveyor]

.
50,000 years!

On a 6000 year old planet.

Amazing!

The rotated polarity in the mid atlantic fracture zone happened 4500 years ago +/-.
.

[TexasGator]

“I’ve been working on reversing the earth’s rotation for a while now. “

It is working.

[TexasGator]

The rotated polarity in the mid atlantic fracture zone happened 4500 years ago +/- 1 Ma.

[DannyTN]

Yeah but the results are too slow.
At this rate, we’ll all be undead when it finally kicks in.

[TexasGator]

“Yeah but the results are too slow.”

Put your methods up on Facebook and watch the results!

[Scrambler Bob]

Would you need a decoder ring when the S points where the N used to be?
= = =

Hopefully the Norte seekers would be reversed.

[Magnum44]

I am challenging my brain for long lost physics knowledge today.

If I recall, like electric motor theory, a rotating magnetic field can generate and electric field, and a rotating electric field can generate a magnetic field.

Now that I am thinking about it, while the worlds mag field is modeled as a dipole (or many dipoles), how its generated is a little fuzzier. Some additional web browsing says that parts of the mantle are thought to be liquid nickel and as it slowly flows about a more solid core, it actually generates current. This electric field, spun by the Earths rotation would subsequently generate the Earths magnetic field.

I use various types of geo physical models in some of my work, but I am not a geologist or geo-physicist, so I am guessing a bit that my understanding is close to correct.

But back to the question of a planet without a mag field, if the planet cant generate an e-field (no liquid core, or non-conductive materials) or it has insufficient rotation, then a magfield may be very weak or not present, unless the planet actually is one big magnet :)

[editor-surveyor]

.
It happened during the Genesis 6 judgemnent, which was about 4500 years ago.

The rotated tiles are of no significance RE: Earth’s magnetic polarity. They spin due to tectonic movement. (much like ball bearings spin when a shaft turns)

[mikrofon]

Wait’ll Bob Mueller and his cadre of Deep-state lawyers get after the magnetic field — they’ll get it to flip…

[Sergio]

Cool, thanks for the information. A very well explained post.

[Sergio]

Comedy science reference...

Explain to me again how sheep’s bladders may be employed to prevent earthquakes. - Monty Python