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Earth's Northern Lights typically dance near the poles, but 41,000 years ago, they lit up skies over North Africa and Australia. New research reveals how dramatically Earth's magnetic field weakened and shifted during an event called the Laschamps geomagnetic excursion, potentially influencing human evolution at a pivotal moment in our history...During the Laschamps excursion, Earth's magnetic field weakened to just 10% of its current strength, while the magnetic poles shifted dramatically away from the geographic poles...Using advanced computer modeling, the research team reconstructed Earth's magnetosphere during five key periods of the excursion. At its peak around 40,977 years ago, Earth's...

Astronomers have just revealed that a day on Uranus is longer than was previously thought, at 17 hours, 14 minutes and 52 seconds. This is 28 seconds longer than the previous estimate, which was made by NASA's Voyager 2 probe during its flyby of the ice giant planet back in 1986. The new figure—which is 1,000 times more accurate—was calculated based on a decade's worth of observations of Uranus's aurorae made by NASA/ESA's Hubble Space Telescope. The long-term data on the planet's auroral emissions enabled the researchers to track the positions of the planet's magnetic poles and, by extension, its...

Hping to keep tabs on the magnetic north's wandering ways, the World Magnetic Model 2025 has been released this week, revealing the latest official predicted placement of Earth's magnetic fields. This version will remain valid until late 2029, during which time we can expect to see the magnetic north pole slowly edge further toward Russia. The new version is of timely importance too as the magnetic north pole’s movement seems to be accelerating. Since the 1830s, the north magnetic pole of Earth has relocated some 2,250 kilometers (1,400 miles) across the upper stretches of the Northern Hemisphere from Canada towards...

The peculiar layers could explain the ice giants' magnetic peculiarities. Uranus (left) and Neptune (right) are the ice blue giants in the outer Solar System. Image credit: Patrick Irwin/University of Oxford/NASA Uranus and Neptune were only visited once by human spacecraft when Voyager 2 passed by them almost 40 years ago. During those visits, scientists measured peculiar magnetic fields unlike those seen around other planets. A recent paper suggests that the Uranus measurements might have been messed up by the Sun, but in general, it has been difficult to explain the behavior. New research suggests that the magnetic weirdness might...

Using NASA’s InSight Mars lander, scientists have precisely measured Mars’ rotation, detecting a subtle acceleration and the planet’s wobble due to its molten core. This study offers unprecedented insights into the Martian core’s size and shape, providing vital information for understanding Mars’ internal structure. Credit: NASA/JPL-Caltech/UArizona. Data sent by the spacecraft before it retired last December has provided new details about how fast the planet rotates and how much it wobbles. Scientists have made the most precise measurements ever of Mars’ rotation, for the first time detecting how the planet wobbles due to the “sloshing” of its molten metal core....

The mystery dates back to Voyager 2's visit to Uranus in January 1986, far before the probe left the solar system in 2018. The spacecraft found that Uranus' magnetic field is asymmetric and tilted roughly 60° away from its spin axis. Additionally, Voyager 2 found that the radiation belts of Uranus, consisting of particles trapped by this magnetic field, are about 100 times weaker than predicted. "It has a magnetic field like no other in the solar system. Most planets that have strong intrinsic magnetic fields, like Earth, Jupiter and Saturn. They have a very 'traditional' magnetic field shape, which...

Scientists believe a slowing or reversing inner core could potentially affect Earth's magnetic field. At the center of the Earth lies a solid metal ball that rotates independently of our spinning planet. Scientists have debated the inner core's rotation speed and direction. However, new research points to the inner core varying speed in recent years. However, researchers are not exactly sure if there are any effects from the inner core slowing down or reversing. Danish seismologist Inge Lehmann discovered the ball-shaped inner core in 1936. The inner core is buried approximately 3,220 miles deep inside Earth. The solid metal ball...

...The heart of our planet has been spinning unusually slowly for the past 14 years, new research confirms. And if this mysterious trend continues, it could potentially lengthen Earth's days — though the effects would likely be imperceptible to us.Earth's inner core is a roughly moon-size chunk of solid iron and nickel that lies more than 3,000 miles (4,800 kilometers) below our feet. It is surrounded by the outer core — a superhot layer of molten metals similar to those in the inner core — which is surrounded by a more solid sea of molten rock, known as the mantle,...

The South Atlantic Anomaly is a location in the southern Atlantic where the innermost portions of the natural zone of energetic charged particles encircling Earth, known as the Van Allen radiation belt, makes its closest approach to the planet. The resulting outflow of energized particles produces a higher yield of ionizing radiation detectable by satellites orbiting Earth. Our planet’s geomagnetic field undergoes constant changes that result from the activity occurring in the Earth’s core, which current models aren’t capable of easily predicting. Because of this, the World Magnetic Model can only offer a good estimate of the Earth’s geomagnetic activity...

The giant iron ball at the center of the Earth appears to be spinning a bit faster than the rest of the planet. The solid 1,500-mile-wide inner core, which is surrounded by fluid, rotates about one-quarter to one-half degree more than the rest of the world every year, scientists from Columbia University's Lamont-Doherty Earth Observatory and the University of Illinois at Urbana-Champaign report in today's issue of the journal Science. The spin of the Earth's core is an important part of the engine that creates the planet's magnetic field, and researcher Xiaodong Song said he believes magnetic interaction is responsible...

A study published Tuesday suggests that Earth has an additional inner core that may tell the tale of a “significant global event from the past.” The highly specialized study published in Nature found that there is a giant metal ball sitting within the Earth’s inner core, known as the innermost inner core (IMIC). The ball is roughly 800 miles, and has been part of geological theory for quite some time, but the results from the study almost conclusively prove its existence (since we can’t get down there and check with our own eyes). The study was conducted by a team...

A new study published in Nature Geoscience by geophysicists Yi Yang and Xiadong Song of Peking University in Beijing explored the nature of movement of Earth’s inner core, largely made up of iron and molten liquids. They found the inner core’s movement recently reduced enough they consider it “paused,” all part of what “seems to be associated with a gradual turning back of the inner core as a part of an approximately seven-decade oscillation.” The last turning point was in the early 1970s. The new study further tracked seismic waves through the core to see how they played out on...

Black holes are powerful cosmic reactors. They supply the energy for quasars and other active galactic nuclei (AGNs). This is due to the interplay between matter and its enormous gravitational and magnetic forces. A black hole technically lacks a magnetic field, but the dense plasma surrounding it as an accretion disc does possess a magnetic field. As plasma spirals around a black hole, the charged particles inside it create an electrical current and magnetic field. The direction of plasma flow does not spontaneously vary, hence the magnetic field is likely rather stable. Imagine the researchers’ amazement when they discovered evidence...

Imagine Earth’s inner core — the dense center of our planet — as a heavy, metal ballerina. This iron-rich dancer is capable of pirouetting at ever-changing speeds. That core may be on the cusp of a big shift. Seismologists reported Monday in the journal Nature Geoscience that after brief but peculiar pauses, the inner core changes how it spins — relative to the motion of Earth’s surface — perhaps once every few decades. And, right now, one such reversal may be underway. This may sound like a setup for a world-wrecking, blockbuster movie. But fret not: Precisely nothing apocalyptic will...

The crack in the magnet field was created by a rare phenomenon called a co-rotating interaction region (CIR) from the Sun. CIRs are large-scale plasma structures generated in the low and mid-latitude regions of the heliosphere – the region surrounding the Sun that includes the solar magnetic field and the solar winds – when fast and slow-moving streams of solar wind interact. Like coronal mass ejections (CMEs), CIRs get flung out from the Sun towards Earth and can contain shockwaves and compressed magnetic fields that cause stormy space weather, which usually presents itself to us as pretty aurorae. This one...

The faster growth under Indonesia's Banda Sea hasn't left the core lopsided. Gravity evenly distributes the new growth—iron crystals that form as the molten iron cools—to maintain a spherical inner core that grows in radius by an average of 1 millimeter per year. But the enhanced growth on one side suggests that something in Earth's outer core or mantle under Indonesia is removing heat from the inner core at a faster rate than on the opposite side, under Brazil. Quicker cooling on one side would accelerate iron crystallization and inner core growth on that side. This has implications for Earth's...

The scans for MH370 revealed that the ocean crust rises and falls in waves that start at the Southeast Indian Ridge and continue outward. The ridge spreads about 35 millimeters in opposite directions every year, and the wave crests, where crust grew faster, are more than 100 kilometers long and repeat every 10-14 kilometers. The researchers estimated when each wave formed by comparing the bathymetry maps to independent measurements and models of the crust's magnetic field. ...Crustal rocks record the polarity of Earth's magnetic field as they form, allowing scientists to trace the age of different sections of ocean crust....

Last Updated: Thursday, 27 March, 2003, 12:02 GMT Is the Earth preparing to flip? By Dr David Whitehouse BBC News Online science editor Finding the shifting magnetic pole It is not just the plot for a far-fetched science-fiction disaster movie. Something unexplained really is happening to the Earth's magnetic field. In recent years, the field has been behaving in ways not previously seen in the admittedly short time it has been monitored. Some researchers think it may presage a geomagnetic reversal when the north and south magnetic poles flip. Such speculation takes place as the science-fiction movie The Core goes...

Researchers are preparing to test the highly controversial theory of a San Diego scientist, J. Marvin Herndon, who thinks a huge, natural nuclear reactor or "georeactor" -- a vast deposit of uranium several miles wide -- exists at Earth's core, thousands of miles beneath our feet... [I]t might help to explain otherwise puzzling phenomena of planetary science, such as fluctuations in the intensity of Earth's magnetic field... If Herndon's theoretical nuclear reactor really exists, then it should be gushing out antineutrinos that would fly through the roughly 4,000 miles of solid rock and emerge at the Earth's surface.

Scientists believe a species of bat has an inbuilt magnetic compass to find its way home over long distances, in addition to its famous echolocation, which guides it around its neighbourhood. Princeton University batologists used radio telemetry aboard a small aircraft to track big brown bats (Eptesicus fuscus) that were released 20 kilometers (12 miles) north of their home. They first tested a "control" group of bats, which headed due south towards the roost without a problem. Two other groups of bats were then exposed to a false magnetic field for 90 minutes, comprising 45 minutes before and 45 minutes...