Is earth an electromagnet? Or is the nickle-iron core a permanent magnet? I thought it was a permanent magnet but now that haig has used the magic word particle "electro" and posted some YouTube links I'm filled with Fear, Uncertainty and Doubt!
Jrrarglblarg, If the Earth was a "permanent magnet" it isn't very permanent now is it?
Earth's Magnetic Field Is Weakening 10 Times Faster Now
The scientists who conducted the study are still unsure why the magnetic field is weakening, but one likely reason is that Earth's magnetic poles are getting ready to flip, said Rune Floberghagen, the ESA's Swarm mission manager. In fact, the data suggest magnetic north is moving toward Siberia
Then there is the more pessimistic view ...
Sunrise from the West: Scientists warn magnetic pole switch
For the last 160 years there has been a steady decrease in the magnetic field of the earth with some warning that a swap of the magnetic poles from north to south would shift the continents so fiercely it would trigger mass earthquakes, rapid climate change, extinctions and global destruction.
Geologic record shows hundreds of pole reversals have occurred through Earth's history.
It is caused by patches of iron atoms in our liquid outer core getting reverse-aligned, as if they were small magnets oriented in the opposite direction to others around them.
If reversed ions expand to the stage they out power the others, the Earth's overall magnetic field "flips".
It is believed a growing patch of reverse-alignment in the liquid core beneath Brazil and the South Atlantic is responsible.
Mr Tarduno said: "(It) has been decreasing for at least 160 years at an alarming rate, leading some to speculate that we are heading toward a reversal."
So our Earth isn't a very good permanent magnet.
What about our variable star the Sun is it a "permanent magnet" ?
Well hardly, what permanent magnet reverses it's polarity every 11 years or so ?
The solar physicists don't know why it reverses it's polarity

What Causes the Sun's Magnetic Field Flip?
While solar physicists know enough about this strange phenomenon to predict when it will occur, its ultimate causes remain mysterious.
"That gets into the whole [solar] cycle, and wondering what that is," Stanford University solar physicist Phil Scherrer told SPACE.com. "We still don't have a really self-consistent mathematical description of what's happening. And until you can model it, you don't really understand it — it's hard to really understand it."
And our variable star is doing some strange things too!
Strange Doings on the Sun
"There is no scientist alive who has seen a solar cycle as weak as this one," said Andrés Munoz-Jaramillo, who studies the solar-magnetic cycle at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.
To complicate the riddle, the sun also is undergoing one of its oddest magnetic reversals on record.
Normally, the sun's magnetic north and south poles change polarity every 11 years or so. During a magnetic-field reversal, the sun's polar magnetic fields weaken, drop to zero, and then emerge again with the opposite polarity. As far as scientists know, the magnetic shift is notable only because it signals the peak of the solar maximum, said Douglas Biesecker at NASA's Space Environment Center.
But in this cycle, the sun's magnetic poles are out of sync, solar scientists said. The sun's north magnetic pole reversed polarity more than a year ago, so it has the same polarity as the south pole.
"The delay between the two reversals is unusually long," said solar physicist Karel Schrijver at the Lockheed Martin Advanced Technology Center in Palo Alto, Calif.
Scientists said they are puzzled, but not concerned, by the unusual delay. They expect the sun's south pole to change polarity next month, based on current satellite measurements of its shifting magnetic fields.
At the same time, scientists can't explain the scarcity of sunspots. While still turbulent, the sun seems feeble compared with its peak power in previous decades. "It is not just that there are fewer sunspots, but they are less active sunspots," Dr. Schrijver said.
So our electromagnetic Sun is weakening and is forecast to continue weakening for the next few solar cycles and maybe for the whole of the 21st century. At the same time our electromagnetic Earth is also weakening. Just a coincidence eh?
Well we shall find out after solar cycle 25 gets past it's maximum.
The Sun is Going to Sleep
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