Earth's Magnetic Field

Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from the Earth's interior to where it meets the solar wind, a stream of charged particles emanating from the Sun. Its magnitude at the Earth's surface ranges from 25 to 65 microtesla (0.25 to 0.65 gauss). Roughly speaking it is the field of a magnetic dipole currently tilted at an angle of about 10 degrees with respect to Earth's rotational axis, as if there were a bar magnet placed at that angle at the center of the Earth. Unlike a bar magnet, however, Earth's magnetic field changes over time because it is generated by a geodynamo (in Earth's case, the motion of molten iron alloys in its outer core).

The North and South magnetic poles wander widely, but sufficiently slowly for ordinary compasses to remain useful for navigation. However, at irregular intervals averaging several hundred thousand years, the Earth's field reverses and the North and South Magnetic Poles relatively abruptly switch places. These reversals of the geomagnetic poles leave a record in rocks that are of value to paleomagnetists in calculating geomagnetic fields in the past. Such information in turn is helpful in studying the motions of continents and ocean floors in the process of plate tectonics.

The magnetosphere is the region above the ionosphere and extends several tens of thousands of kilometers into space, protecting the Earth from the charged particles of the solar wind and cosmic rays that would otherwise strip away the upper atmosphere, including the ozone layer that protects the Earth from harmful ultraviolet radiation. Read More

Coronal Mass Ejections (CMEs)

Coronal Mass Ejections (CMEs) reach Earth affecting planetary magnetics, sparking geomagnetic storms, shifting ocean and jet stream currents in the Pacific Ring of Fire, creating unusual and extreme global weather patterns, creating unstoppable Earth changes, and affecting the behavior patterns of all sentient life forms.

South Atlantic Anomaly

The South Atlantic Anomaly (SAA) is an area where the Earth's inner Van Allen radiation belt comes closest to the Earth's surface, dipping down to an altitude of 200 kilometres (120 mi). This leads to an increased flux of energetic particles in this region and exposes orbiting satellites to higher-than-usual levels of radiation. The effect is caused by the non-concentricity of the Earth and its magnetic dipole. The SAA is the near-Earth region where the Earth's magnetic field is weakest relative to an idealized Earth-centered dipole field. The area of the SAA is confined by the intensity of Earth's magnetic field at less than 32,000 nanotesla at sea level, which corresponds to the dipolar magnetic field at ionospheric altitudes. However, the field itself varies in intensity as a gradient. Read more

Marker for the collapse of key Atlantic current discovered   Live Science - February 9, 2024

A vital Atlantic current that includes the Gulf Stream and keeps our climate in check may be giving off a warning sign of collapse.

Ocean system that moves heat gets closer to collapse, which could cause weather chaos, study says   PhysOrg - February 9, 2024

Marker for the collapse of key Atlantic current discovered   Live Science - February 9, 2024

A vital Atlantic current that includes the Gulf Stream and keeps our climate in check may be giving off a warning sign of collapse.

NASA is actively monitoring a strange anomaly in Earth's magnetic field: a giant region of lower magnetic intensity in the skies above the planet, stretching out between South America and southwest Africa   Science Alert - March 23, 2023

This vast, developing phenomenon, called the South Atlantic Anomaly, has intrigued and concerned scientists for years, and perhaps none more so than NASA researchers. The space agency's satellites and spacecraft are particularly vulnerable to the weakened magnetic field strength within the anomaly, and the resulting exposure to charged particles from the Sun. The South Atlantic Anomaly (SAA) - likened by NASA to a 'dent' in Earth's magnetic field, or a kind of 'pothole in space' - generally doesn't affect life on Earth, but the same can't be said for orbital spacecraft (including the International Space Station), which pass directly through the anomaly as they loop around the planet at low-Earth orbit altitudes.

NASA researchers track slowly splitting 'dent' in Earth's magnetic field   PhysOrg - August 17, 2020

A small but evolving dent in Earth's magnetic field can cause big headaches for satellites. Earth's magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun. But over South America and the southern Atlantic Ocean, an unusually weak spot in the field - called the South Atlantic Anomaly, or SAA - allows these particles to dip closer to the surface than normal. Particle radiation in this region can knock out onboard computers and interfere with the data collection of satellites that pass through it - a key reason why NASA scientists want to track and study the anomaly.

The South Atlantic Anomaly May Go Back Far Longer Than Anybody Knew   Science Alert - July 22, 2020

For years, scientists have been gripped by the existence of a strange anomaly weakening Earth's magnetic field. It's located in the midst of the South Atlantic ocean, extending all the way from South America to the west coast of southern Africa. This giant, puzzling expanse of reduced magnetic intensity - which in recent times looks to be splitting into two divided entities - means the region offers less protection against harmful radiation from the Sun for Earth's satellites. That's a problem for spacecraft today. But perhaps the greatest significance of the 'South Atlantic Anomaly' is what it might mean for tomorrow: specifically, whether the mysterious phenomenon foreshadows the beginnings of a complete polar reversal of Earth's magnetic field. Such giant magnetic flips have occurred many times in our planet's history, and some scientists have speculated that the South Atlantic Anomaly could be a kind of precursor to these rare global transitions.

In the News ...

Earth's Magnetic Field Is Not The Same At The North And South Poles   IFL Science - May 29, 2024

The magnetic field is not something that is static. The Earth’s magnetosphere is being altered by the solar wind coming from the Sun. During periods of high activity, like now, it is squished more than when the Sun is calmer. These differences have been used to explain why magnetic field observations differ if taken near the Earth's surface or in space. This was at least the conventional assumption. New work argues that there is more than that at play. Researchers used data from between 2014 and 2020 since 98.1 percent of the time within that period had geomagnetic conditions of low to moderate. Still, even when the magnetosphere was not being wildly affected by space weather, there were significant differences between observations. In particular, these were more pronounced in the north and south polar regions.

Life Blossomed When Earth's Magnetic Field Nearly Collapsed 590 Million Years Ago   Science Alert - May 3, 2024

According to new research, the temporary weakening of the magnetic shielding might have been anything but a biological catastrophe. In fact, it may have boosted oxygen levels, creating prime conditions for early life to blossom.

Ancient Rocks Reveal Earth's Magnetic Field Existed 3.7 Billion Years Ago   Science Alert - April 28, 2024

That was a time when Earth may have been still wrapped in water, and early life was only just starting to emerge – and the newly discovered traces of the planetary magnetosphere reveal that it was surprisingly similar to the invisible structure that still protects Earth today.

Decade of Swarm satellite data unveils new insights into Earth's magnetic field and core dynamics   Watchers - March 26, 2024

Launched in 2013, the European Space Agency’s (ESA) Swarm mission, consisting of three satellites, has provided a decade of invaluable data on Earth’s magnetic field and enabled significant advances in understanding the mechanisms behind its slow changes. Researchers have utilized this extensive dataset, alongside advanced numerical simulations, to derive new insights into the swirling motion of liquid iron in Earth’s outer core and its impact on the magnetic field. The findings, including the identification of a core jet stream and magnetic waves, contribute to improving predictions of future magnetic field fluctuations.

The importance of the Earth’s magnetic field goes beyond the immediate benefits of radiation protection and technological support. It is intricately linked to the broader environmental and climate systems that define our planet’s habitability.

Rare pure sine wave detected in Earth's magnetic field   Watchers - October 19, 2023

The event, termed a 'pulsation continuous' or Pc3 in this case, lasted for over 20 minutes and was caused by a gentle gust of solar wind. The event was unexpected as it occurred near the Solar Maximum, contrasting with the typical appearance of Pc3 waves during low geomagnetic activity in the Solar Minimum.

Eerie sounds triggered by plasma waves hitting Earth's magnetic field captured in new NASA sound clip   Live Science - April 23, 2023

NASA has converted years of satellite data on Earth's magnetosphere into eerie sound clips that can be used by citizen scientists to help make new discoveries.

Shock wave from sun has opened up a crack in Earth's magnetic field, and it could trigger a geomagnetic storm   Live Science - December 19, 2022
The shockwave's origins aren't exactly known, but scientists think it could have come from a coronal mass ejection launched by the sunspot AR3165, a fizzing region on the sun's surface that released a flurry of at least eight solar flares on Dec. 14, causing a brief radio blackout over the Atlantic Ocean. Sunspots are areas on the sun's surface where powerful magnetic fields, created by the flow of electrical charges, knot into kinks before suddenly snapping. The resulting release of energy launches bursts of radiation called solar flares, or plumes of solar material called coronal mass ejections (CMEs). Once launched, CMEs travel at speeds in the millions of miles per hour, sweeping up charged particles from the solar wind to form a giant, combined wavefront that (if pointed toward Earth) can trigger geomagnetic storms.

Slight shifts in magnetic field preceded California earthquakes   PhysOrg - October 8, 2022
Researchers studying intermediate to large earthquakes in California have discovered detectable changes in the local magnetic field that occur 2-3 days before an earthquake.

Giant Magnetic Waves Have Been Discovered Oscillating Around Earth's Core   Science Alert - May 25, 2022

Scientists studying satellite data of Earth have identified something inside Earth we've never seen before: a new type of magnetic wave that sweeps around the surface of our planet's core, every seven years. This discovery could offer insight into how Earth's magnetic field is generated, and provide clues of our planet's thermal history and evolution – that is, the gradual cooling of the planetary interior.

Standing Waves Unexpectedly Discovered at The Edge of Earth's Magnetosphere   Science Alert - October 7, 2021

Buffeted by a constant stream of charged particles from the solar wind, Earth is not without its protection. Our planet is wrapped in a bubble of magnetism called the magnetosphere, spun out from deep inside the planet's interior. As the solar wind blows, scientists assumed that the edges of this bubble would ripple in a series of energy waves in the plasma, generated by the interaction between the solar wind and magnetosphere, along the direction that the wind is blowing. But now they've discovered a surprise: some of the waves generated stand still.

The effects of solar flares on Earth's magnetosphere   PhysOrg - April 23, 2021
Solar flares are highly explosive events that can last from a few minutes to hours and can be detected using X-rays or optical devices.

The Adams Event: "The Hitchhiker's Guide to the Galaxy" author Douglas Adams told us that the Answer to the Ultimate Question of Life, the Universe, and Everything is 42.   Mysterious Universe - February 20, 2021

Ancient relic points to a turning point in Earth's history 42,000 years ago  PhysOrg - February 19, 2021

This dramatic turning point in Earth's history laced with electrical storms, widespread auroras, and cosmic radiation was triggered by the reversal of Earth's magnetic poles and changing solar winds. The temporary breakdown of Earth's magnetic field 42,000 years ago sparked major climate shifts that led to global environmental change and mass extinctions.

Earth's magnetic field flipped 42,000 years ago, creating a climate 'disaster'   Live Science - February 19, 2021

A reversal in Earth's magnetic field thousands of years ago plunged the planet into an environmental crisis that may have resembled "a disaster movie," scientists recently discovered. Our planet's magnetic field is dynamic and, numerous times, it has flipped - when the magnetic North and South Poles swap places. In our electronics-dependent world, such a reversal could seriously disrupt communication networks. But the impact could be even more serious than that, according to the new study. For the first time, scientists have found evidence that a polar flip could have serious ecological repercussions. Their investigation connects a magnetic field reversal about 42,000 years ago to climate upheaval on a global scale, which caused extinctions and reshaped human behavior.

Earth's magnetic field broke down 42,000 years ago and caused massive sudden climate change   PhysOrg - February 19, 2021

The world experienced a few centuries of apocalyptic conditions 42,000 years ago, triggered by a reversal of the Earth's magnetic poles combined with changes in the Sun's behavior. That's the key finding of our new multidisciplinary study, published in Science.

NASA watches as weird 'dent' in Earth's magnetic field splits in two - August 18, 2020

There's something very strange happening high above South America and the nearby Atlantic Ocean, and NASA is on the case. Meet the South Atlantic Anomaly, a strange dent in Earth's magnetic field that is growing and splitting. It's been there for decades, but over time the anomaly has slowly changed. Although you'd never notice anything was wrong from the ground, for satellites, changes to the magnetic field that envelopes Earth can be a big deal - hence NASA's interest in the anomaly and its activities.

NASA Keeping Tabs on the Growing Rip in Earth's Magnetic Field   Mysterious Universe - August 18, 2020

The European Space Agency (ESA) weighed in earlier this year about the South Atlantic Anomaly (SAA) – the mysterious dent in Earth's magnetic field over the South Atlantic that is being weakened to the point of splitting apart by the planet's molten metal outer core churning around and shifting old tectonic plates on top of each other so that they block the outer core from forming the magnetic field. Now NASA decided it's time to reveal its concern about the SAA and how it's affected NASA's satellites.

NASA researchers track slowly splitting 'dent' in Earth's magnetic field   PhysOrg - August 18, 2020
A small but evolving dent in Earth's magnetic field can cause big headaches for satellites. Earth's magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun. But over South America and the southern Atlantic Ocean, an unusually weak spot in the field - called the South Atlantic Anomaly, or SAA - allows these particles to dip closer to the surface than normal. Particle radiation in this region can knock out onboard computers and interfere with the data collection of satellites that pass through it - a key reason why NASA scientists want to track and study the anomaly.

Simulations show magnetic field can change 10 times faster than previously thought   PhysOrg - July 6, 2020
A new study by the University of Leeds and University of California at San Diego reveals that changes in the direction of the Earth's magnetic field may take place 10 times faster than previously thought. Their study gives new insight into the swirling flow of iron 2800 kilometers below the planet's surface and how it has influenced the movement of the magnetic field during the past hundred thousand years. Our magnetic field is generated and maintained by a convective flow of molten metal that forms the Earth's outer core. Motion of the liquid iron creates the electric currents that power the field, which not only helps guide navigational systems but also helps shield us from harmful extra terrestrial radiation and hold our atmosphere in place.

Earth's magnetic field changes 10 times faster than once thought   Live Science - July 8, 2020
Our planet's dynamic magnetic field can change direction far more quickly than scientists suspected. This bubble of magnetism holds our atmosphere in place and protects us from harmful cosmic radiation and solar winds. But a few times every million years, the field's polarity reverses and the magnetic North Pole and South Pole trade places. The last time this happened was about 780,000 years ago, and the process was previously estimated to take thousands of years, shifting at a rate of about one degree per year.

Possible connection between ice and Earth's magnetic history   PhysOrg - June 29, 2020
To measure the magnetism of the 'ice cores' created in a lab, where a sensitive magnetometer and been installed allowed scientists to measure the very slightest of magnetic moments. The team found a small, but definitely detectible magnetic moment that matched the magnetic fields applied to their ice samples.

'Vigorous' magnetic field oddity spotted over South Atlantic   Live Science - May 26, 2020

The Mysterious Anomaly Weakening Earth's Magnetic Field Seems to Be Splitting   Science Alert - May 26, 2020
New satellite data from the European Space Agency (ESA) reveal that the mysterious anomaly weakening Earth's magnetic field continues to evolve, with the most recent observations showing we could soon be dealing with more than one of these strange phenomena. The South Atlantic Anomaly is a vast expanse of reduced magnetic intensity in Earth's magnetic field, extending all the way from South America to southwest Africa.

Since our planet's magnetic field acts as a kind of shield - protecting Earth from solar winds and cosmic radiation, in addition to determining the location of the magnetic poles - any reduction in its strength is an important event we need to monitor closely, as these changes could ultimately have significant implications for our planet. At present, there's nothing to be alarmed about. The ESA notes that the most significant effects right now are largely limited to technical malfunctions on board satellites and spacecraft, which can be exposed to a greater amount of charged particles in low-Earth orbit as they pass through the South Atlantic Anomaly in the skies above South America and the South Atlantic Ocean.

Scientists explain magnetic pole's wanderings   BBC - May 7, 2020

European scientists think they can now describe with confidence what's driving the drift of the North Magnetic Pole. It's shifted in recent years away from Canada towards Siberia. And this rapid movement has required more frequent updates to navigation systems, including those that operate the mapping functions in smartphones. A team, led from Leeds University, says the behavior is explained by the competition of two magnetic "blobs" on the edge of the Earth's outer core. Changes in the flow of molten material in the planet's interior have altered the strength of the above regions of negative magnetic flux.

Ancient Australian Crystals Unlock History of Earth's First Magnetic Field   Live Science - January 20, 2020
Tiny crystals in Australia are helping scientists unlock the ancient history of our planet's first magnetic field, which disappeared hundreds of millions of years ago. And the crystals show that this field was a lot more powerful than anyone believed. That, in turn, could help answer a question about why life emerged on Earth. Those tiny, old crystals are locked in rocks that date to well over half a billion years ago. At the time, tiny magnetic particles floated in the molten rock. But as that rock cooled, the particles, which aligned to the magnetic field orientation at the time, locked into place. And those particles still sit in a pose suggesting that they were influenced by a much more powerful magnetic field than scientists had assumed, a new study reveals.

Earth's Magnetic North Pole Continues Drifting, Crosses Prime Meridian   Live Science - December 17, 2019
Magnetic north has been lurching away from its previous home in the Canadian Arctic toward Siberia at a rate of about 34 miles (55 kilometers) a year over the past two decades. Magnetic north has been lurching away from its previous home in the Canadian Arctic toward Siberia at a rate of about 34 miles (55 kilometers) a year over the past two decades.

Earth's Magnetic Poles Can Flip Much More Often Than Anyone Thought   Live Science - October 4, 2019

Hot liquid that churns around Earth's outer core powers a gigantic magnetic field that's been hugging our planet since its infancy, protecting it from harmful solar radiation. But this magnetic field is known to get restless - and a couple of times every million years or so, the poles flip, and magnetic south becomes magnetic north and vice versa. Now, a new study suggests that the magnetic poles can flip much more frequently than scientists thought. That's what seems to have happened around 500 million years ago during the Cambrian period, when Earth's creatures were undergoing evolutionary growth spurts, transforming into more complex life-forms. To understand the workings of the magnetic field during this time, a group of researchers from the Institute of Physics of the Globe of Paris and the Russian Academy of Sciences collected sediment samples from an outcrop in northeastern Siberia.

What If Earth's Magnetic Field Disappeared? It wouldn't be great, but it wouldn't be like a disaster movie, either.   Live Science - September 29, 2019

Extending from Earth like invisible spaghetti is the planet's magnetic field. Created by the churn of Earth's core, this field is important for everyday life: It shields the planet from solar particles, it provides a basis for navigation and it might have played an important role in the evolution of life on Earth. But what would happen if Earth's magnetic field disappeared tomorrow? A larger number of charged solar particles would bombard the planet, putting power grids and satellites on the fritz and increasing human exposure to higher levels of cancer-causing ultraviolet radiation. In other words, a missing magnetic field would have consequences that would be problematic but not necessarily apocalyptic, at least in the short term. And that's good news, because for more than a century, it's been weakening. Even now, there are especially flimsy spots, like the South Atlantic Anomaly in the Southern Hemisphere, which create technical problems for low-orbiting satellites.

What happens when magnetic north and true north align?   PhysOrg - September 17, 2019
At some point in recent weeks, a once-in-a-lifetime event happened for people at Greenwich in the United Kingdom. Magnetic compasses at the historic London area, known as the home of the Prime Meridian, were said to have pointed directly at the north geographic pole for the first time in 360 years. This means that, for someone at Greenwich, magnetic north (the direction in which a compass needle points) would have been in exact alignment with geographic north. Geographic north (also called "true north") is the direction towards the fixed point we call the North Pole. Magnetic north is the direction towards the north magnetic pole, which is a wandering point where the Earth's magnetic field goes vertically down into the planet.

Earth's last magnetic field reversal took far longer than once thought   PhysOrg - August 7, 2019
Earth's magnetic field seems steady and true - reliable enough to navigate by. Yet, largely hidden from daily life, the field drifts, waxes and wanes. The magnetic North Pole is currently careening toward Siberia, which recently forced the Global Positioning System that underlies modern navigation to update its software sooner than expected to account for the shift. And every several hundred thousand years or so, the magnetic field dramatically shifts and reverses its polarity: Magnetic north shifts to the geographic South Pole and, eventually, back again. This reversal has happened countless times over the Earth's history, but scientists have only a limited understanding of why the field reverses and how it happens.

New findings on Earth's magnetic field - Researchers show that the iron oxide hematite remains magnetic deep within Earth's mantle   Science Daily - June 6, 2019
The well-known sources of the magnetic field that surrounds Earth are the deep inside core and Earth's crust. Earth's mantle, on the other hand, has been considered to be 'magnetically dead' for the most part. Now researchers show that a form of iron oxide can also retain its magnetic properties in Earth's mantle.

Scientists Find Evidence That Your Brain Can Sense Earth's Magnetic Field   Live Science - March 18, 2019
In the latest study researchers exposed subjects to magnetic fields. They then scanned their brains using electroencephalography (EEG). In some individuals, the scientists at Caltech and the University of Tokyo found a change in brain waves that showed the brain was actively processing the information. The researchers found a marked decrease in alpha waves in the brain when they exposed certain individuals to a magnetic field indicating north. Alpha waves are given off when the mind is at rest. A dropping off occurs when the brain receives input from the senses.

Earth's Magnetic North Pole Was Moving So Fast, Geophysicists Had to Update the Map   Live Science - February 5, 2019
Previously, the World Magnetic Model, which tracks Earth's roving magnetic north pole, was updated in 2015 with the intent that the model would last until 2020. But the magnetic north pole had other plans. It began lurching unexpectedly away from the Canadian Arctic and toward Siberia more quickly than expected.

Earth's Magnetic Field Nearly Disappeared 565 Million Years Ago   Live Science - January 30, 2019
Five hundred and sixty-five million years ago, Earth's magnetic field almost disappeared. But a geological phenomenon might have saved it, a new study suggests. Earth's then-liquid core likely began to solidify around that time, which strengthened the field. This is important because the magnetic field protects our planet and its inhabitants from harmful radiation and solar winds - streams of plasma particles thrown our way by the sun. Scientists figured out what our planet's core was like back then by looking at crystals the size of grains of sand.

Earth's lucky escape 565 million years ago: Study finds our planet's magnetic field was 'on the verge of collapse'   Daily Mail - January 29, 2019
Earth narrowly avoided a catastrophic collapse of the magnetic field that protects our planet 565 million years ago, it has been revealed. Researchers say that it is had collapsed, life on Earth would have faced severe challenges as the solar wind would have stripped the planet of its atmosphere and bombarded the surface with harmful radiation. Researchers found that, luckily, our planet's core solidified 'right in the nick of time', recharging Earth's magnetic field when it was at its weakest point.

Earth's Magnetic Pole Is Wandering, Lurching Toward Siberia   Live Science - January 14, 2019

Earth's north magnetic pole is on the move, unpredictably lurching away from the Canadian Arctic and toward Siberia. It's wandered so much, that the current representation of the entire globe's magnetic field, just updated in 2015, is now out of date. And so, geologists have come up with a new model.

Scientists warn Earth's magnetic North Pole has begun moving 'erratically' at speeds so fast they are having to issue an emergency update to maps used by electronic navigation systems   Daily Mail - January 11, 2019
Earth's magnetic fields are shifting - and scientists are unsure why. Researchers say the magnetic North Pole is 'skittering' away from Canada, towards Siberia. The problem has got so bad, researchers around the world are scrambling to update a global model of the fields. Called the World Magnetic Model, it underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones.

Earth's magnetotail: First-ever views of elusive energy explosion   Science Daily - November 15, 2018
Researchers have captured a difficult-to-view singular event involving 'magnetic reconnection' - the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion - in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Earth's magnetic field measured using artificial stars at 90 kilometers altitude   PhysOrg - November 15, 2018
The mesosphere, at heights between 85 and 100 kilometers above the Earth's surface, contains a layer of atomic sodium. Astronomers use laser beams to create artificial stars, or laser guide stars (LGS), in this layer for improving the quality of astronomical observations. In 2011, researchers proposed that artificial guide stars could also be used to measure the Earth's magnetic field in the mesosphere. An international group of scientists has recently managed to do this with a high degree of precision. The technique may also help to identify magnetic structures in the solid Earth's lithosphere, to monitor space weather, and to measure electrical currents in the part of the atmosphere called ionosphere.

Scientists develop a new way to remotely measure Earth's magnetic field   PhysOrg - October 4, 2018
Researchers in Canada, the United States and Europe have developed a new way to remotely measure Earth's magnetic field—by zapping a layer of sodium atoms floating 100 kilometres above the planet with lasers on the ground. The technique not only measures magnetic field strength at an altitude that has traditionally been hidden, it has the side benefit of providing new information on space weather and atomic processes occurring in the region.

Earth's Magnetic Field Is Drifting Westward, and Nobody Knows Why   Live Science - May 16, 2018
Over the 400 years or so that humans have been measuring Earth's magnetic field, it has drifted inexorably to the west. Now, a new hypothesis suggests that weird waves in Earth's outer core may cause this drift. Over the 400 years or so that humans have been measuring Earth's magnetic field, it has drifted inexorably to the west. Now, a new hypothesis suggests that weird waves in Earth's outer core may cause this drift. The slow waves, called Rossby waves, arise in rotating fluids. They're also known as "planetary waves," and they're found in many large, rotating bodies, including on Earth in the oceans and atmosphere and on Jupiter and the sun. The slow waves, called Rossby waves, arise in rotating fluids. They're also known as "planetary waves," and they're found in many large, rotating bodies, including on Earth in the oceans and atmosphere and on Jupiter and the sun.

Video: Space view of Earth's magnetic rocks   BBC - March 21, 2017
It is the best depiction yet of the magnetism retained in Earth's rocks, as viewed from space. The map was constructed using data from Europe's current Swarm mission, combined with legacy information from a forerunner satellite called Champ. Variations as small as 250km across are detectable. Clearly seen are the "stripes" of magnetism moving away from mid-ocean ridges - the places on the planet where new crust is constantly produced. This pattern - the consequence of periodic changes in Earth's polarity being locked into the minerals of cooling volcanic rock - was one of the key pieces of evidence for the theory of plate tectonics.

Ceramic Pottery Reveals an Ancient Geomagnetic Field Spike   Live Science - February 13, 2017
More than 2,500 years ago in the ancient Near East, the Earth's geomagnetic field was going gangbusters. During the late eighth century B.C., a new study finds, the magnetic field that surrounds the planet was temporarily 2.5 times stronger than it is today. Researchers know about these fluctuations thanks to the bureaucracy of Judah, an ancient kingdom situated around what is now Jerusalem. Pottery jugs from between the eighth and second centuries B.C. bear administrative stamps that changed with the political situation. Unbeknown to the people firing these jugs, the act of heating locked information about the Earth's geomagnetic field into minerals present in the clay. Because the stamps provide precise information about when the pots were fired, the study allows a detailed look at geomagnetic changes over 600 years.

NASA's THEMIS sees Auroras move to the rhythm of Earth's magnetic field   Science Daily - September 12, 2016
For the first time, scientists have directly mapped Earth's fluctuating magnetic field and resulting electrical currents to aurora, thanks to northern lights observations from NASA's THEMIS mission. The majestic auroras have captivated humans for thousands of years, but their nature -- the fact that the lights are electromagnetic and respond to solar activity -- was only realized in the last 150 years. Thanks to coordinated multi-satellite observations and a worldwide network of magnetic sensors and cameras, close study of auroras has become possible over recent decades. Yet, auroras continue to mystify, dancing far above the ground to some, thus far, undetected rhythm.

Just what sustains Earth's magnetic field anyway?   PhysOrg - June 1, 2016
Earth's magnetic field shields us from deadly cosmic radiation, and without it, life as we know it could not exist here. The motion of liquid iron in the planet's outer core, a phenomenon called a "geodynamo," generates the field. But how it was first created and then sustained throughout Earth's history has remained a mystery to scientists. Our planet accreted from rocky material that surrounded our Sun in its youth, and over time the most-dense stuff, iron, sank inward, creating the layers that we know exist today - core, mantle, and crust. Currently, the inner core is solid iron, with some other materials that were dragged along down during this layering process. The outer core is a liquid iron alloy, and its motion gives rise to the magnetic field.

Missing link in metal physics explains Earth's magnetic field   Science Daily - January 28, 2015
Earth's magnetic field shields the life on our planet's surface from cosmic rays. It is generated by turbulent motions of liquid iron in Earth's core. Iron is a metal, which means it can easily conduct a flow of electrons. New findings show that a missing piece of the traditional theory explaining why metals become less conductive when they are heated was needed to complete the puzzle of this field-generating process.

Earth's magnetic field could flip within a human lifetime   Science Daily - October 14, 2014
Earth's last magnetic reversal took place 786,000 years ago and happened very quickly, in less than 100 years - roughly a human lifetime. The rapid flip, much faster than the thousands of years most geologists thought, comes as new measurements show the planet's magnetic field is weakening 10 times faster than normal and could drop to zero in a few thousand years.

Earth's Magnetic Field Is Weakening 10 Times Faster Now   Live Science - July 8, 2014
Earth's magnetic field, which protects the planet from huge blasts of deadly solar radiation, has been weakening over the past six months, according to data collected by a European Space Agency (ESA) satellite array called Swarm. The biggest weak spots in the magnetic field - which extends 370,000 miles (600,000 kilometers) above the planet's surface - have sprung up over the Western Hemisphere, while the field has strengthened over areas like the southern Indian Ocean, according to the magnetometers onboard the Swarm satellites - three separate satellites floating in tandem.

Earth's 6-Year Twitch Changes Day Length   Live Science - July 10, 2013
Periodic wobbles in Earth's core change the length of a day every 5.9 years. Teasing out this subtle cycle, which subtracts and adds mere milliseconds to each day, also revealed a match between abrupt changes in the length of day and Earth's magnetic field. During these short-lived lurches in the magnetic field intensity, events called geomagnetic jerks, Earth's day also shifts by 0.1 millisecond, the researchers report. Since 1969, scientists have detected 10 geomagnetic jerks lasting less than a year. Seemingly negligible, these fleeting variations are mighty to those who study the planet and its core. All of a sudden, a planet changes its spin like a figure skater open or closing her arms. The rotational effect helps scientists understand what's happening inside the Earth's core. Shifts in the magnetic field also provide clues to the inaccessible iron core. But their source remains a mystery.

Why Earth's Magnetic Field Is Wonky   Live Science - July 18, 2012
The solution to a long-standing puzzle, why magnetic north sits off the coast of Canada, rather than at the North Pole, may have been found in the strange, lopsided nature of Earth's inner core. The inner core is a ball of solid iron about 760 miles (1,220 kilometers) wide. It is surrounded by a liquid outer core (mostly iron and nickel), a rocky, viscous mantle layer and a thin, solid crust. As the inner core cools, crystallizing iron releases impurities, sending lighter molten material into the liquid outer core. This upwelling, combined with the Earth's rotation, drives convection, forcing the molten metal into whirling vortices. These vortices stretch and twist magnetic field lines, creating Earth's magnetic field. Currently, the center of the field, called an axis, emerges in the Arctic Ocean west of Ellesmere Island, about 300 miles (500 kilometers) from the geographic North Pole.

Can humans sense the Earth's magnetism?   PhysOrg - June 21, 2011
For migratory birds and sea turtles, the ability to sense the Earth's magnetic field is crucial to navigating the long-distance voyages these animals undertake during migration. Humans, however, are widely assumed not to have an innate magnetic sense.

Humans May Have 'Magnetic' Sixth Sense   Live Science - June 21, 2011
Humans may have a sixth sense after all, suggests a new study finding that a protein in the human retina, when placed into fruit flies, has the ability to detect magnetic fields.

Human eye protein senses Earth's magnetism   BBC - June 21, 2011
A light-sensitive protein in the human eye has been shown to act as a "compass" in a magnetic field, when it is present in flies' eyes.

Reading Earth's magnetic history   PhysOrg - March 4, 2011
In order to date environmental events from Earth's history such as meteorite impacts or climate change - geologists have long studied variations in slow-growing seafloor sedimentary rocks called ferromanganese crusts that build up in layers over the eons. The layers can be dated by various means, such as by analyzing radioactive isotopes, but those methods don't provide accurate dating on small scales: a millimeter of rock, for example, can include information that spans as much as hundreds of thousands of years.

African rocks record ancient magnetic field   BBC - May 4, 2010
Scientists have managed to push back the date for the earliest known presence of a magnetic field on Earth by about 250 million years.

Monarch Butterflies Reveal a Novel Way in Which Animals Sense Earth's Magnetic Field   Science Daily - January 27, 2010
Building on prior investigation into the biological mechanisms through which monarch butterflies are able to migrate up to 2,000 miles from eastern North America to a particular forest in Mexico each year, neurobiologists at the University of Massachusetts Medical School (UMMS) have linked two related photoreceptor proteins found in butterflies to animal navigation using the Earth's magnetic field.

'Magnetricity' observed and measured for the first time   PhysOrg - October 18, 2009
The magnetic equivalent of electricity in a 'spin ice' material: atom sized north and south poles in spin ice drift in opposite directions when a magnetic field is applied. A magnetic charge can behave and interact just like an electric charge in some materials, according to new research led by the London Centre for Nanotechnology.

Ancient Earth's Magnetic Field Was Structured Like Today's Two-pole Model   Science Daily - October 5, 2009
Princeton University scientists have shown that, in ancient times, the Earth's magnetic field was structured like the two-pole model of today, suggesting that the methods geoscientists use to reconstruct the geography of early land masses on the globe are accurate. The findings may lead to a better understanding of historical continental movement, which relates to changes in climate. By taking a closer look at the 1.1 billion-year-old volcanic rocks on the north shore of Lake Superior, the researchers have found that Earth's ancient magnetic field was a geocentric axial dipole -- essentially a large bar magnet centered in the core and aligned with the Earth's spin axis.

Rare Magnetar Discovered: Giant Eruption Reveals 'Dead' Star   Science Daily - June 16, 2009
NASA's Swift satellite reported multiple blasts of radiation from a rare object known as a soft gamma repeater, or SGR. Now, astronomers report an in-depth study of these eruptions using the European Space Agency's XMM-Newton and International Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellites.

Reversals of Earth's Magnetic Field Explained by Small Core Fluctuations   PhysOrg - April 23, 2009
Based on studies of old volcanic basalt, scientists know that the Earth's magnetic field reverses at irregular intervals, ranging from tens of thousands to millions of years. Volcanic basalt rock contains magnetite, and when the rock cools, its magnetic properties are frozen, recording the Earth's magnetic field of the time. With this data, scientists estimate that the last magnetic field reversal occurred about 780,000 years ago.

Leaks Found in Earth's Protective Magnetic Field    Live Science - December 17, 2008
Scientists have found two large leaks in Earth's magnetosphere, the region around our planet that shields us from severe solar storms. The leaks are defying many of scientists' previous ideas on how the interaction between Earth's magnetosphere and solar wind occurs: The leaks are in an unexpected location, let in solar particles in faster than expected and the whole interaction works in a manner that is completely the opposite of what scientists had thought.

A Giant Breach in Earth's Magnetic Field    NASA - December 16, 2008
NASA's five THEMIS spacecraft have discovered a breach in Earth's magnetic field ten times larger than anything previously thought to exist. Solar wind can flow in through the opening to "load up" the magnetosphere for powerful geomagnetic storms. But the breach itself is not the biggest surprise. Researchers are even more amazed at the strange and unexpected way it forms, overturning long-held ideas of space physics.

Lava flows reveal clues to magnetic field reversals PhysOrg - September 25, 2008
Ancient lava flows are guiding a better understanding of what generates and controls the Earth's magnetic field - and what may drive it to occasionally reverse direction. The main magnetic field, generated by turbulent currents within the deep mass of molten iron of the Earth's outer core, periodically flips its direction, such that a compass needle would point south rather than north. Such polarity reversals have occurred hundreds of times at irregular intervals throughout the planet's history - most recently about 780,000 years ago - but scientists are still trying to understand how and why.

Movement of North Magnetic Pole is accelerating PhysOrg - December 9, 2005
After some 400 years of relative stability, Earth's North Magnetic Pole has moved nearly 1,100 kilometers out into the Arctic Ocean during the last century and at its present rate could move from northern Canada to Siberia within the next half-century. If that happens, Alaska may be in danger of losing one of its most stunning natural phenomena – the Northern Lights.

Pulsar Gives Insight On Ultra Dense Matter And Magnetic Fields Science Daily - December 20, 2004
A long look at a young pulsar with NASA's Chandra X-ray Observatory revealed unexpectedly rapid cooling, which suggests that it contains much denser matter than previously expected. The pulsar's cool temperature and the vast magnetic web of high-energy particles that surrounds it have implications for the theory of nuclear matter and the origin of magnetic fields in cosmic objects.

The Earth's magnetic field is fading BBC - December 31, 2003
Scientists have known for some time that the Earth's magnetic field is fading. Like a Kryptonite-challenged Superman, its strength has steadily and mysteriously waned, leaving parts of the planet vulnerable to increased radiation from space. Some satellites already feel the effects. What is uncertain is whether the weakened field is on the way to a complete collapse and a reversal that would flip the North and South Poles. Compasses pointing North would then point South.