Category: The Sun

Detective work by a team of space-weather experts has discovered the truth about a historical event that had been thought to be the first-ever case of technological disruption by geomagnetic activity from the sun, but has now been shown to have taken place seven years later.

From it being too hot or too wet to leaves on the track or cows on the line, there's a fine tradition of what the British public consider to be flimsy excuses for delays on the trains. Yet an 1871 edition of the journal Nature describes a very different event that caused a train departing Exeter, in Devon on the south-west coast of the U.K., to be delayed by 16 minutes: a solar storm that flooded the railway signals' electrical telegraph network with current.

"The Exeter train delay is a fascinating story because it sits right at the point where emerging technologies first began to encounter the realities of the space environment," said Jim Wild, who is a professor of space physics at Lancaster University and also the President of the Royal Astronomical Society, in a statement.

The event has frequently been cited as the first example of a solar storm disrupting technology on Earth, but when a team led by Wild went back through historical records to investigate further, they found that things didn't add up.

The original report in Nature stated that the electrical disturbance occurred at 10:05pm local time on Oct. 18, 1841. However, Wild's team found that particular train line didn't open until 1846.

So, they delved deeper into the history books to figure out the truth.

"Our research has a hint of a detective story — piecing together a wide range of archived records to better understand a historically severe space-weather event," said team-member Mike Hapgood, a space weather expert at RAL Space, which is the UK's National Space Laboratory, in Oxfordshire.

Combining data from railway timetables, old newspapers, plus historic reports of solar observations and the northern lights and digitized geomagnetic data, Wild and Hapgood's team were able to conclude that the most likely date for the train delay was Oct. 18, 1848, which coincided with a strong solar storm that hit Earth.

This revised date knocks it off top spot in the chronological list of such events. The first recorded disruption to electrical technologies is now a disturbance on the Midland railway network, which had lines covering much of the U.K., in March 1847.

"Although this means it is not the earliest recorded space weather impact, it remains one of the first clear examples of solar activity disrupting critical infrastructure," Wild said. "It also demonstrates the value of combining scientific records with contemporary newspaper reports and archival documents when reconstructing historic space weather events."

The case reminds us that space weather has been a hazard to technology and modern systems for a long time, and isn't just a recent problem.

"Society has been experiencing the effects of space weather on technology for almost as long as electrical technologies have existed," said Wild.

The most dramatic example is the aforementioned Carrington event of 1859, representing the most significant solar storm on record as it caused telegraph poles to spark and battery power supplies to be disrupted. By this point, telegraph operators had grown used to electrical disturbances associated with auroral activity, but even the Carrington storm shocked them — quite literally in some cases, as extra current ran down the telegraph lines — with its ferocity. Should a similar event occur today, it would cause huge black outs, knock out power grids, disrupt communications and fry satellites.

"While today's space weather [monitoring] capabilities are far more advanced than anything available in the 1800s, the modern technologies we depend on are also much more vulnerable to solar storms," said Hapgood.

The current solar cycle 25 peaked in Oct. 2024 and we are just beginning to come out of an extended period of maximum activity. However, it remains to be seen how the rest of this cycle will play out before reaching solar minimum in about 2030. We've already seen severe geomagnetic storms caused by space weather in May 2024 — will we experience another powerful storm before the decade is out?

Our star and primary energy source that makes life on this planet possible may also be a cosmic cannibal. That's according to new research that suggests the sun may have swallowed a super-Earth planet billions of years ago in its early history. And our star may still be hiding the evidence.

The scientists behind this research think that the fingerprints of this violent consumption of a planet may still exist within the solar interior. Super-Earths are common occupants of other planetary systems, and these findings can explain why the solar system lacks such a world.

"Our new study suggests that a planet several times more massive than Earth may have fallen into the young sun and left a lasting chemical imprint deep inside it," Mutlu Yildiz, of Ege University, Turkey, said in a statement.

Yildiz and colleagues theorize that the sun's act of planetary infanticide may help to explain differences between observations of the sun and what is predicted by models of stellar evolution. This includes the depth of the sun's convection zone and the so-called sound-speed structure just below the convection zone.

It could also explain why the surface of the sun is depleted of the element lithium.

"By modelling the sun's evolution and comparing the results with precise observations of its interior, we find that the ingestion of a super-Earth could help explain long-standing differences between standard solar models and observations, including subtle changes in the sun's internal structure and its depleted lithium abundance," Yildiz said. "We were interested in whether these problems might have a common origin in the early chemical history of the sun."

The researcher explained that young stars like the sun during its infancy are surrounded by vast flattened clouds of gas and dust called protoplanetary discs, where substantial amounts of material can move between the disc and the star.

"Since planets are made of material that is chemically different from the gas in the disc, we wondered whether the early engulfment of a planet could have left a chemical signature inside the young sun," Yildiz said.

What happened to the sun's planetary meal?

Using advanced stellar evolution software, Yildiz and colleagues tested their idea by investigating different ways the sun could have swallowed a planet.

Their results found the best fit for the sun's current characteristics was the cannibalism of a planet between five and ten times the mass of the Earth, a type of planet called a super-Earth. This could explain the strange, unpredicted characteristics of the sun.

We thought planetary engulfment might affect the solar structure but did not expect the calculations to converge on such a specific super-Earth mass range," said Professor Yildiz. "That was one of the most interesting outcomes of the study."

The team's research is supported by previous studies that suggests one or more super-Earth planets could have formed with the orbit of Mercury, the closest planet to the sun.

These worlds would have then migrated through the protoplanetary disk surrounding the infant sun before crashing into the star.

But this new study leaves open the possibility that something else, other than this violent collision with the sun, may explain the discrepancies in measurements of the sun's interior and its lithium content. The team's model doesn't need a planet to have been totally engulfed by the sun.

Currently, this idea is based on computer modelling and unexplained solar features, but the researchers think that the predicted structural and chemical signature of a planetary engulfment could still exist within our star and could be detected.

"The earlier work proposed that a super-Earth could have formed and migrated into the young sun. Our paper asks whether the sun itself could still carry observable evidence that such an engulfment actually happened, and we believe it could," Yildiz concluded. "The next step is to see if these fingerprints can be independently detected."

The research was published on Thurs (Sept. 10) in the journal Monthly Notices of the Royal Astronomical Society.

A misbehaving coronal mass ejection (CME) that blew out a hidden cloud of charged particles aimed at Earth has been tracked by a record 17 spacecraft spread throughout the solar system, revealing the CME to be surprisingly lopsided.

CMEs are "burps" from the sun – huge clouds of magnetized plasma belched out from the sun's hot outer atmosphere, the corona, by the energy resulting from a solar flare. The magnetized CME cloud then expands out into the solar system, and the charged particles that the cloud contains are a significant radiation hazard to astronauts, spacecraft and even passengers on jet liners, but they also have a beautiful side as they can trigger the beautiful lights of the aurora when they intercept Earth.

CMEs occur on a regular basis, but one that erupted from the sun at 00:48 UT (7:48 p.m. ET) on Dec. 15, 2024 proved to be rather special.

"We used observations from 17 spacecraft to track and characterize this CME," Adrienn Luspay-Kuti of Johns Hopkins University Applied Physics Laboratory, who led the research that drew all the observations together, told Space.com. "This was a record number of spacecraft for tracking and characterizing a single CME, and gave us an exceptionally detailed view of how the CME evolved."

The previous record had been 10 spacecraft, but they had mostly been in a rough line from the sun through to the Earth and beyond, meaning that their measurements were somewhat one-dimensional. This time, for the December 2024 CME, the spacecraft were spread far and wide, not just at different distances from the sun, but also substantially wide of the Earth–sun line.

They revealed that the CME had two asymmetric lobes, one moving faster than the other. One of those lobes, which headed for Earth and Mars, would have gone unseen, obscured by the larger but slower lobe that left the sun at a tangent, were it not for the wide spread of the spacecraft.

"Our observations showed a fast lobe propagating through the Earth–Mars sector and a much slower lobe farther west toward STEREO-A," said Luspay-Kuti. STEREO-A is one half of NASA's two-spacecraft space weather monitoring system known as the Solar Terrestrial Relations Observatory.

The onset of the CME was seen by the joint NASA–ESA Solar and Heliospheric Observer (SOHO), which has been constantly monitoring the sun for more than 30 years. Yet it only saw the slower lobe that erupted at an angle to Earth; the faster lobe heading for our planet was missed, obscured by the slower, larger lobe.

The CME was next detected at a distance from the sun of 0.35 astronomical units (AU; 1 AU is the distance of Earth from the sun) on Dec. 16 moving through space near Mercury and the European Space Agency's BepiColombo mission (which finally arrives into orbit around the innermost planet in November 2026).

The next detection, on Dec. 17, was of the "hidden" component arriving at Earth, where a multitude of spacecraft picked it up. The CME was not strong enough to produce significant aurorae. Intriguingly Europe's Solar Orbiter mission, on an elongated orbit around the sun and at the time 0.94 AU from the sun and just 10 degrees off the Earth–sun line, did not detect the CME. This non-detection was actually vital since it helped to constrain the shape of the CME.

Then on Dec. 18, the slower moving lobe reached NASA's STEREO-A spacecraft, which orbits the sun at the same distance as Earth — 1 AU —- but substantially ahead of Earth in its orbit. The lobe that intersected the Earth had an average velocity of 522 miles (840 kilometers) per second, but the other lobe dragged its feet, moving at an average of 332 miles (534 km) per second from the sun and past BepiColombo and STEREO-A. In fact, by the time it reached STEREO-A, it had slowed to about 248.5 miles (400 km) per second. Both lobes decelerated as a result of friction with the regular solar wind that the CME was overtaking, and the range of velocities measured in the CME told researchers that the solar eruption was not traveling as a single, unified front.

Beyond Earth NASA's Europa Clipper mission, on which Luspay-Kuti is the Principal Investigator for the spacecraft's Plasma Instrument for Magnetic Sounding (PIMS) experiment, detected the faster moving lobe at 1.19 AU as the spacecraft was cruising to Mars for a gravity assist to help it on its journey to Jupiter. At the red planet, the now-defunct MAVEN mission also detected the CME on Dec. 19 to Dec. 20.

To have not only so many spacecraft follow the progress of a CME but also enough spacecraft off the Earth–sun line to measure the shape of the CME, at least in two dimensions, is a significant step forward in understanding and forecasting the propagation of CMEs.

"This matters for future human exploration because a missed CME can mean losing valuable warning time," said Luspay-Kuti. "Fast CMEs can drive shocks that accelerate high-energy particles, which can pose a radiation hazard to astronauts outside Earth's protective magnetic field. This is why observations from multiple viewpoints, including spacecraft away from the sun–Earth line and planetary missions operating during their cruise phase, will become increasingly important for space-weather forecasting as human exploration moves further from Earth."

The asymmetrical double-lobed structure of this particular CME was certainly a surprise. The cause of the asymmetry remains unclear at present, though Luspay-Kuti told Space.com that researchers are investigating. The main question is, how frequent are asymmetric CMEs?

"In the context of previous observations, this event is at the most extreme end of observed CME variability," said Luspay-Kuti. "Are highly asymmetric CMEs actually fairly common but we fail to recognize them because we don't have enough observational coverage, or are they genuinely rare?"

The 17 spacecraft that detected or imaged the CME across some or all of its various stages – the bow shock and turbulent sheath ahead of the magnetic cloud, the CME itself and the turbulent wake left in the solar wind after its passing – were the following: SOHO (initial imaging), BepiColombo, NASA's Solar Dynamics Observatory, STEREO-A, the four spacecraft of the Magnetospheric Multiscale (MMS) mission, the two spacecraft of the ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the sun) mission, NASA's Wind, ACE (Advanced Composition Explorer), GOES (Geostationary Operational Environmental Satellite) and DSCOVR (Deep Space Climate Observatory) missions, Europa Clipper, MAVEN and Solar Orbiter, the latter of which made measurements but did not detect the CME.

In the future, these missions will be joined by the European Space Agency's Vigil mission that will watch for space weather when it launches in 2031 for the sun–Earth L5 Lagrange point, 60 degrees behind Earth in its orbit and therefore providing additional off-axis monitoring.

The findings were published on Aug. 19 in the journal Science Advances.

Scientists have captured the sharpest image ever of our sun's surface. This view has revealed incredible new details about the inner mechanisms driving stellar activity.

What is it?

An international team of researchers using the U.S. National Science Foundation's Inouye Solar Telescope has captured the highest-resolution view of the sun's surface.

In analyzing observations from this telescope, the team, made up of researchers from the National Solar Observatory, the NSF NCR High Altitude Observatory and the German Max Planck Institut für Sonnensystemforschung, discovered strange patterns on the sun's surface. The whirling patterns, they found, are actually evidence of what's called Kelvin-Helmholtz instability (KHI), or instability that happens when there is a change in velocity of fluids.

Why is it incredible?

This image is groundbreaking. Capturing the highest-resolution view of the sun's surface is a massive accomplishment, and in the time-lapse video above, you can even see the fluid dynamics on the surface of the sun in motion.

But this view is much more than a beautiful, high-resolution image. These observations have revealed swirls on the sun's surface at the edges of the magnetic areas, allowing the team to identify KHI on the sun's surface. This fluid instability has long been suspected on the sun, but these observations are the first time they have ever been directly seen like this.

“We believe that the discovery of Kelvin-Helmholtz Instability in the solar photosphere, backed up by analysis of numerical simulations, is a major step forward in our understanding of the dynamics and evolution of solar and stellar plasma, and will serve as a basis for future discoveries," David Boboltz, the deputy director at the National Solar Observatory, said in a statement.

A paper describing these findings was published recently in the journal Nature.

For several years now, astronomers who study the sun have faced a little mystery — our star seemed to hold too little silver. Whenever scientists examined the sun's outer layers, they've seen significantly less silver than they've expected to find.

Where, then, did the missing silver go?

As it turns out, this mystery may finally be solved. Newly published research suggests that the sun's missing silver may have been hiding in plain sight all along.

At first, the real mystery might seem to be why you'd seek silver in the sun at all. After all, 98.5% of the sun's mass is made from lightweight hydrogen and helium. Silver is just a tiny fraction of the remaining 1.5%, which also includes traces of other heavy elements like iron and copper.

These trace elements can illuminate the history of the cosmos. Silver is thought to form when dying stars violently explode in supernovas. When astronomers find silver in the sun and other stars, they can retrace the silver's origins and how stars have evolved over the eons.

"By studying the light of stars of different types and ages, we hope to understand where silver is formed in the universe, and how it has been distributed throughout the Milky Way over time," says Sema Caliskan, the lead author of the research and now a postdoc at the University of Liège in Belgium, in a statement.

Silver is particularly interesting because it's also found in utterly ancient meteorites called CI chondrites. These meteorites formed from the same primordial matter that created the sun, 4.6 billion years ago. As a result, when scientists break into CI chondrites that have fallen to Earth, they expect to find silver levels that match those they see in the sun.

Astronomers can measure the latter from afar by looking at sunlight's spectral lines. As light streams out from the sun's heart, it crashes into the atoms of our star's outer layers, which absorb the light at certain wavelengths. Look at a spectrum of sunlight, and you'll see dark lines where light has been absorbed. Atoms of different elements absorb different wavelengths, so each element leaves a distinct fingerprint.

Scientists can pore over these spectral fingerprints to reconstruct what elements created them and in what quantities. Therein lies the mystery: The sun seemed to contain much less silver than CI chondrites would indicate. This missing silver is a source for confusion in the sun's history.

Caliskan and her colleagues wondered if astronomers were missing something. They could not visit the sun in person, but they could still find where the silver might be hidden by simulating the sun's atoms on a computer. If they could create a high-silver model that still spawned the low-silver spectral lines, that model could be a good guess for the silver's whereabouts.

Other scientists had tried this before to limited success, but their simulations had been relatively simple. As light strikes an atom, the light has all sorts of intricate effects on the atom's innards. These effects can alter how the atom absorbs the light and, therefore, change how astronomers see that light.

Past models hadn't accounted for many of these tricky "non-equilibrium effects", because simulating them is far easier said than done. They're messy and complex and they vary a great deal from atom to atom.

In fact, no known scientists had ever tried to simulate a silver atom with non-equilibrium effects before Caliskan and her fellow investigators took on the challenge. They tried with their best guesses and the power of the Tetralith supercomputer in Linköping, Sweden.

Indeed, these non-equilibrium effects seem to explain the silver mystery. Based on their model, Caliskan and colleagues calculated that the sun holds 55% more silver than astronomers have measured.

This isn't a perfect match for the CI chondrites, but it's close enough that investigators can rule out any extraordinary cause. Instead, the missing silver may have been right there, in the sun all along, simply occluded from astronomers' view by tricks of physics. Next, Caliskan and colleagues plan to use this method to simulate other types of stars.

They published their work in the journal Astronomy & Astrophysics in July 2026.

The most powerful solar storms to strike Earth may pack a bigger punch than scientists realized, according to a new study that suggests the impacts of extreme space weather have been underestimated.

Researchers found evidence that the apparent upper limit on Earth's response to the strongest solar storms may be an artifact of how solar wind has been measured rather than a true physical ceiling. If confirmed, the findings suggest that rare "once-in-a-thousand-year" geomagnetic storms could have a greater impact on modern technology than current estimates indicate, according to a statement.

"Our planet's magnetic field does a really great job of protecting us against many space weather effects and so they often just show up as glitches or beautiful aurora," Maria Walach, co-author of the study from Lancaster University, said in the statement. "There are however extreme cases."

Solar storms occur when eruptions from the sun, such as coronal mass ejections and solar flares, send clouds of charged particles hurtling toward Earth. While they can produce spectacular auroras, they can also disrupt satellites, GPS, radio communications and power grids.

History has shown the damage even less extreme storms can cause. The 1859 Carrington Event, the strongest geomagnetic storm on record, disrupted telegraph systems around the world and pushed auroras from their usual high-latitude skies near the Arctic and Antarctic to locations as far south as the tropics. Another powerful storm in 1989 collapsed Quebec's power grid, leaving millions without electricity, while the 2003 "Halloween storms" disrupted satellites, GPS and radio communications.

While the study doesn't suggest that an unprecedented solar storm is imminent, it argues that scientists may need to rethink how they estimate the severity of the rarest events — an increasingly important challenge as modern society grows more dependent on satellites and other vulnerable technologies.

The researchers traced the apparent upper limit to where most solar wind measurements are collected. Many observations of extreme events come from spacecraft near the Sun-Earth Lagrange Point 1 (L1), about 1 million miles (1.5 million kilometers) upstream of Earth. Because the strongest solar wind tends to weaken somewhat before reaching Earth, comparing L1 measurements with conditions at our planet can make it appear that Earth's upper atmosphere stops responding to increasingly intense solar wind, even when it does not.

To test that idea, the team analyzed more than one million solar wind measurements collected by NASA spacecraft orbiting much closer to Earth, where the solar wind directly interacts with our planet's magnetic field. Those observations showed that electrical currents flowing through Earth's upper atmosphere continued to increase alongside stronger solar wind, with no sign of the previously assumed upper limit. The results suggest that exceptionally powerful solar storms could generate stronger geomagnetic disturbances — and greater impacts on satellites, communications systems and power grids — than earlier estimates predicted.

"Fortunately, these very extreme cases are rare, but this also means we have limited data to work with and only time will tell what happens at the very extreme one-in-a-thousand-year kind of event," Walach said in the statement.

The study comes as the sun remains near the peak of its roughly 11-year solar cycle, known as solar maximum, when sunspots, solar flares and coronal mass ejections become more frequent. During the current cycle, strong geomagnetic storms have repeatedly sent auroras far beyond their usual polar skies.

In May 2024, the strongest geomagnetic storm in more than two decades illuminated skies across much of the United States and Europe while causing intermittent disruptions to high-frequency radio communications, GPS-guided equipment and some satellite operations. Although significant, that event was far less powerful than the Carrington Event — or the even rarer storms the new study suggests may be possible.

The findings were published July 15 in the journal Nature.

The mystery of how the sun's corona, which is its outer atmosphere, reaches millions of degrees could have a surprising explanation: cosmic dust riding the magnetic waves carrying plasma on the solar wind.

"For decades, researchers have focused mainly on how electrons, ions, magnetic fields and plasma waves transport and dissipate energy in the solar atmosphere," said lead researcher Syed Ayaz of the University of Alabama in Huntsville in a statement. "Our work adds a new ingredient to this picture: dust grains."

The finding came courtesy of NASA's Parker Solar Probe, which has flown closer to the sun than any other spacecraft, skirting the corona at a distance of 6.1 million kilometers (3.8 million miles). If you've ever witnessed a total solar eclipse, or even seen a photograph of one, then you will be familiar with the corona — the ghostly tendrils of light that surround the eclipsed sun. Those tendrils are formed from plasma, or ionized gas, at temperatures in excess of a million degrees Fahrenheit, compared to the sun's visible surface, the photosphere, which radiates at about 9,932 degrees Fahrenheit (5,500 degrees Celsius). At those temperatures, the photosphere outshines the corona only because the plasma in the corona is so sparsely distributed. This is why the only time we can see the corona is during a total solar eclipse, when the photospheric glare is blocked.

Parker does not carry a cosmic dust detector, and that's because until now dust has not been considered a serious component of the solar atmosphere. Indeed, in the high temperatures of the solar corona it had been thought that dust could not survive for very long and would therefore have no impact.

However, Parker does host a bunch of antennas and magnetometers collectively referred to as the FIELDS experiment, designed to measure the electromagnetic field and radio emissions in the solar corona. The antennas kept picking up unexpected spikes in voltage, which according to Ayaz and his team are produced by clouds of charged particles created when tiny dust grains slam into Parker at high velocity.

These dust grains have accrued an electrostatic charge, which can interact with the electromagnetic field carried by the solar wind as it leaves the sun, which in turn can influence waves of plasma reverberating through that electromagnetic field called Alfvén waves.

There are two possible, competing ways in which dust can affect the Alfvén waves, which in turn could determine how energy is dumped into the corona, heating it. On one hand, the mass of the dust can act to provide extra inertia to the plasma as it rides the solar wind, allowing the plasma energy to be transported across wider distances. On the other hand, the electric charge on the dust grains can bolster the interactions between charged particles in the plasma, the Alfvén waves and the solar electromagnetic field.

"If dust mass dominates, [Alfvén] wave energy may travel farther into the corona," said Ayaz. "If dust-charge effects dominate, the energy may be released more locally as particle heating."

The balance between these two effects can therefore control where and when energy is deposited into the corona, focusing it in areas and causing temperatures there to rise dramatically.

Future solar missions are now going to have to start taking dust into account, said Ayaz, with dedicated detectors designed to measure dust's properties close to the Sun.

"The bigger question is fascinating," said Ayaz. "Is dust simply passing through the near-Sun environment, or is it helping shape how electromagnetic energy becomes heat and solar-wind motion?"

The new discovery was reported on July 1 in The Astrophysical Journal.