The northern lights are caused by the solar wind, a stream of charged particles from the sun that interacts with Earth’s magnetic field. As charged particles strike Earth’s magnetic field, they accelerate down its magnetic field lines at the north and south poles, exciting particles in the atmosphere to create ovals of green and red.
Archiv: Magnetfelder / Magnetosphären / magnetic fields / magnetospheres
Early riser! The Sun is already starting its next solar cycle
(July 19, 2024)
The current solar cycle, named Cycle 25 because it is the 25th since 1755 when extensive recording of solar sunspot activity began, started in 2019.
It is not expected to end for another six years but the first signs that the next solar cycle is beginning have been spotted by researchers from the University of Birmingham and presented at the Royal Astronomical Society‘s National Astronomy Meeting in Hull.
Interactive: Why auroras are surging during one of the weakest solar cycles in 126 years
(February 12, 2026)
Scientists call the current cycle Solar Cycle 25, the 25th numbered cycle since recordkeeping began in the 1700s. Even though it may feel like the northern lights have been more common in recent years, Solar Cycle 25 ranks among the lowest of the past 126 years.
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Earth’s magnetic field has been slowly weakening for more than a century, which means our natural shield isn’t quite as strong as it used to be. That doesn’t create solar storms, but it can change how much of that energy actually makes it through when a strong one hits.
Animation: Heliosphere
(March 9, 2022)
This complex environment surrounds the planets and ultimately has a crucial effect on the formation, evolution, and destiny of planetary systems. For one thing, our heliosphere acts as a giant shield, protecting the planets from galactic cosmic radiation. Earth is additionally shielded by its own magnetic field, the magnetosphere, which protects us not only from solar and cosmic particle radiation but also from erosion of the atmosphere by the solar wind. Planets without a shielding magnetic field, such as Mars and Venus, are exposed to such processes and have evolved differently.
NASA‘s studies of the heliosphere include research into: how the solar wind behaves near Earth; what causes and sustains magnetic and electric fields around other planets; how does the heliosphere interact with the interstellar medium; what do the boundaries of the heliosphere look like; what is the origin and evolution of the solar wind and the interstellar cosmic rays; and what contributes to the habitability of exoplanets.
Energy coupling between the solar wind and the magnetosphere
(June 1981)
This paper describes in detail how we are led to the first approximation expression for the solar wind-magnetosphere energy coupling function ɛ, which correlates well with the total energy consumption rate U T of the magnetosphere. It is shown that ɛ is the primary factor which controls the time development of magnetospheric substorms and storms. The finding of this particular expression ɛ indicates how the solar wind couples its energy to the magnetosphere; the solar wind and the magnetosphere constitute a dynamo. In fact, the power P generated by the dynamo can be identified as ɛ by using a dimensional analysis. Furthermore, the finding of ɛ indicates that the magnetosphere is closer to a directly driven system than to an unloading system which stores the generated energy before converting it to substorm and storm energies.
Physics Professor Gerard Fasel and Seaver Students Present Solar-Terrestrial Interactions at the American Geophysical Union Conference
(January 13, 2026)
Coining the term “near-Earth astrophysics,” Fasel has devoted much of his career to investigating solar-terrestrial interactions between the Sun and Earth, using the aurora borealis to obtain clues regarding the coupling mechanisms between the solar wind and the Earth’s terrestrial magnetic field.
“Stars have winds,” says Fasel. “And this includes our Sun. While solar wind is a relatively continuous stream of particles that interact with the Earth’s magnetic field, the Sun can also produce powerful solar storms. These storms expel billions of charged particles [plasma] coupled to magnetic fields, called coronal mass ejections, which bang up into the Earth’s magnetic field.”
The Earth’s magnetic field lines, Fasel explains, “act like wires” on which these particles travel down into the Earth’s upper atmosphere, specifically the ionosphere. The aurora is an end result of this interaction, where high-energy electrons collide with oxygen to produce green light, while those of lower energy produce a raspberry-red color.
Swarm probes weakening of Earth’s magnetic field
(May 20, 2020)
Over the last 200 years, the magnetic field has lost around 9% of its strength on a global average. A large region of reduced magnetic intensity has developed between Africa and South America and is known as the South Atlantic Anomaly.
Part of Earth’s Magnetic Field is Getting Weaker in ‘Vigorously’ Developing Anomaly, Scientists Say
(May 22, 2020)
According to the European Space Agency (ESA), the magnetic field has lost around 9 percent of its strength over the preceding two centuries. One section of the magnetic field has been found to have weakened considerably since 1970.
This patch, called the South Atlantic Anomaly, sits between Africa and South America. Over the last 50 years, it has grown and moved farther west at a rate of roughly 12 miles per year. However, in the last five years, part of the anomaly appears to have split off into a cell which the ESA calls a „second center of minimum intensity“ located southwest of Africa.
Is Earth’s Magnetic Shield Eroding?
(29.3.2018)
The strength of Earth’s main magnetic field is currently about 29.5 microteslas, down 5 microteslas, or 14 percent from its strength three centuries ago.
We know this. There is no question of this.
Magnetic effect on CO 2 solubility in seawater: A possible link between geomagnetic field variations and climate
(August 2008)
Correlations between geomagnetic-field and climate parameters have been suggested repeatedly, but possible links are controversially discussed. Here we test if weak (Earth-strength) magnetic fields can affect climatically relevant properties of seawater. We found the solubility of air in seawater to be by 15% lower under reduced magneticfield (20 mT) compared to normal field conditions (50 mT). The magnetic-field effect on CO2 solubility is twice as large, from which we surmise that geomagnetic field variations modulate the carbon exchange between atmosphere and ocean. A 1% reduction in magnetic dipole moment may release up to ten times more CO2 from the surface ocean than is emitted by subaerial volcanism.
Ocean Tides and Magnetic Fields
(December 30, 2016)
Earth’s magnetic field is built up from many contributing sources ranging from the planet’s core to the magnetosphere in space. Untangling and identifying the different sources allows geomagnetic scientists to gather information about the individual processes that combine to create the full field.
One contributor is the ocean. But how do the tides affect Earth’s magnetic field? Seawater is an electrical conductor, and therefore interacts with the magnetic field. As the tides cycle around the ocean basins, the ocean water essentially tries to pull the geomagnetic field lines along. Because the salty water is a good, but not great, conductor, the interaction is relatively weak. The strongest component is from the regular lunar tide that happens about twice per day (actually 12.42 hours).
Watch: Auroras Light Up Skies Worldwide
November 13, 2025
People across the United States weren’t the only ones treated to a spectacular celestial show. This week’s intense geomagnetic storm illuminated the night sky around the world. Check out some of the most stunning displays from Europe to Mongolia to Australia.
Early riser! The Sun is already starting its next solar cycle
(July 19, 2024)
The current solar cycle, named Cycle 25 because it is the 25th since 1755 when extensive recording of solar sunspot activity began, started in 2019.
It is not expected to end for another six years but the first signs that the next solar cycle is beginning have been spotted by researchers from the University of Birmingham and presented at the Royal Astronomical Society‘s National Astronomy Meeting in Hull.
The next solar cycle – Solar Cycle 26 – is already beginning
(July 23, 2024)
Solar max affects activity on the sun’s surface. Sunspots, flares and coronal mass ejections are all more rampant at solar maximum. This leads to a surge in electromagnetic energy hurtling toward Earth, making auroras visible more often and at lower altitudes.
The current solar cycle – Cycle 25 – started in 2019. It has the name Cycle 25 because it’s the 25th since 1755, when extensive recording of solar sunspot activity began.
It is not expected to end for another six years, but researchers have spotted the first signs that the next solar cycle is beginning. Researchers from the University of Birmingham presented their findings at the Royal Astronomical Society’s National Astronomy Meeting in Hull on July 18, 2024.
11 Years Charting Edge of Solar System
Jun 11, 2020
Far, far beyond the orbits of the planets lie the hazy outlines of the magnetic bubble in space that we call home.
This is the heliosphere, the vast bubble that is generated by the Sun’s magnetic field and envelops all the planets. The borders of this cosmic bubble are not fixed. In response to the Sun’s gasps and sighs, they shrink and stretch over the years.
Now, for the first time, scientists have used an entire solar cycle of data from NASA’s IBEX spacecraft to study how the heliosphere changes over time. Solar cycles last roughly 11 years, as the Sun swings from seasons of high to low activity, and back to high again. With IBEX’s long record, scientists were eager to examine how the Sun’s mood swings play out at the edge of the heliosphere. The results show the shifting outer heliosphere in great detail, deftly sketch the heliosphere’s shape — a matter of debate in recent years, and hint at processes behind one of its most puzzling features. These findings, along with a newly fine-tuned data set, are published in The Astrophysical Journal Supplements on June 10, 2020.
Magnetic effect on CO 2 solubility in seawater: A possible link between geomagnetic field variations and climate
(August 2008)
Correlations between geomagnetic-field and climate parameters have been suggested repeatedly, but possible links are controversially discussed. Here we test if weak (Earth-strength) magnetic fields can affect climatically relevant properties of seawater. We found the solubility of air in seawater to be by 15% lower under reduced magneticfield (20 mT) compared to normal field conditions (50 mT). The magnetic-field effect on CO2 solubility is twice as large, from which we surmise that geomagnetic field variations modulate the carbon exchange between atmosphere and ocean. A 1% reduction in magnetic dipole moment may release up to ten times more CO2 from the surface ocean than is emitted by subaerial volcanism.
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The fact that the MF effect is similar among the molecular gases suggests that effects seen with air are not due to the paramagnetic susceptibility of O 2, which is too small to explain the observed magnetic-field effects in terms of magnetization effects.
Mysterious link between Earth’s magnetism and oxygen levels baffles scientists
(June 13, 2025)
The strength of Earth’s magnetic field seems to rise and fall in line with the abundance of oxygen in the planet’s atmosphere, a study of geological records spanning the past half a billion years has found.
Strong link between Earth’s oxygen level and geomagnetic dipole revealed since the last 540 million years
(June 13, 2025)
We search for possible observational evidence for such a relationship by examining evolutions of the virtual geomagnetic axial dipole moment and the atmospheric oxygen level over the past 540 million years. We find that both exhibit strong linearly increasing trends, coupled with a large surge in magnitude between 330 and 220 million years ago.
NASA Scientists Find Ties Between Earth’s Oxygen and Magnetic Field
(June 18, 2025)
Data for both Earth’s magnetic field and oxygen extend over comparable ranges in databases that myriad geophysicists and geochemists have compiled. Until now, the authors of the new study say, no scientists had made a detailed comparison of the records.
A Weak Spot in Earth’s Magnetic Field Is Going from Bad to Worse
(November 10, 2025)
The observations by the European Space Agency’s Swarm trio of satellites found that Earth’s already weak magnetic field over the South Atlantic Ocean—a region known as the South Atlantic Anomaly (SAA)—is getting worse and that it has grown by an area half the size of continental Europe since 2014. At the same time, a region over Canada where the field is particularly strong has shrunk, while another strong field region in Siberia has grown, the measurements show.
The Earth’s Magnetic Field Is Rapidly Weakening—And Scientists Are Tracking Every Change
(July 29, 2025)
1. The Magnetic Field’s Essential Role
Earth’s magnetic field acts as a protective barrier against the relentless bombardment of solar wind and cosmic rays. Without this shield, high-energy particles from the Sun would strip away our atmosphere, exposing living organisms to dangerous radiation.
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12. Atmospheric and Climate Connections
Researchers are investigating whether a weaker magnetic field could alter Earth’s atmosphere or climate.
World Magnetic Model Receives Upgrade
(August 19, 2025)
In addition to the WMM2025, the release includes the first-ever World Magnetic Model High Resolution (WMMHR), which features a spatial resolution of approximately 300 km at the equator, an improvement upon the standard spatial resolution of 3,300 km at the equator. Higher resolution provides greater directional accuracy, making this a significant improvement for users.
In addition to the introduction of the WMMHR, this release comes with some other key changes:
– The WMM predicts an intensification of the South Atlantic Anomaly (SAA) between 2025 and 2030.
– The WMM uncertainty analysis presented in the report has been updated with new data, resulting in a slightly revised error budget.
– The WMM report provides altitude ranges for varying levels of geomagnetic activity.
Magnetic North Pole shift brings updates to World Magnetic Model 2025
(December 25, 2024)
2 versions of the model are:
WMM2025: Standard model with a spatial resolution of 3 300 km (2 050 miles) at the equator.
WMMHR2025: A high-resolution model with an improved spatial resolution of approximately 300 km (186 miles), offering enhanced directional accuracy.
“We’re delighted to join with NOAA and BGS to publish WMM2025 and WMMHR2025, and we encourage users, where possible, to transition to the higher resolution model,” Mike Paniccia, a geodetic Earth scientist and the program manager for the World Magnetic Model (WMM) at the National Geospatial-Intelligence Agency (NGA), stated.
Swarm probes weakening of Earth’s magnetic field
(May 20, 2020)
Over the last 200 years, the magnetic field has lost around 9% of its strength on a global average. A large region of reduced magnetic intensity has developed between Africa and South America and is known as the South Atlantic Anomaly.
Aurora Borealis Displays STUNNED Americans Across the Country
The northern lights lit up the night sky across America on Tuesday, dazzling stargazers from New Hampshire to the heartland with eerie green and orange streaks of cosmic fire.
The U.S. saw vivid northern lights as far south as Florida — and more could be coming
The Aurora Borealis was spotted in a large swath of states, including Idaho, Iowa, Missouri, New Mexico, New York, Oklahoma, South Dakota, Tennessee, Texas and Washington state. Northern lights were visible as far south as parts of Florida and Alabama, a relatively rare occurrence that highlights the severity of this week‘s storms.
Rare solar storm lights up Northern California skies
A surge in solar activity fueled the vibrant display as the sun reached the peak of its 11-year solar cycle, a period marked by a sharp increase in sunspots and geomagnetic storms.
Around 2019–2020, the sun was at its quietest point; however, with more frequent bursts of solar wind erupting from those sunspots, Earth is now experiencing more substantial and more frequent auroral events.