NASA and Lancaster University scientists have discovered that extreme solar storms pose a far greater threat to global technology than previously believed, according to a new study published in the journal Nature.
Researchers led by Dr. Nithin Sivadas of NASA Goddard Space Flight Center found that Earth's upper atmosphere has no known upper limit to induced electrical currents during severe solar events.
Maria Walach, a space physicist at Lancaster University who co-authored the study, said that in extreme cases satellites fall unexpectedly to Earth or communications and GPS signals are lost.
For decades, the scientific community operated under the assumption that the planet's magnetic response reached a saturation ceiling during intense solar particle ejections. Scientists believed that no matter how strong a solar storm was, electrical currents in the upper atmosphere stopped growing after reaching a maximum limit.
The new research reveals that this long-held belief was merely a statistical illusion caused by measurement inaccuracies in traditional monitoring methods.
Flaws in historical solar wind measurement
The research team identified that the apparent saturation was caused by a statistical phenomenon known as measurement regression. Historical data on extreme solar wind relied heavily on spacecraft positioned at Lagrange point 1, located more than 1.5 million kilometres from Earth.
Lagrange point 1 is a position in space where the gravitational forces of the Sun and Earth balance out, allowing scientific satellites to hover stably between the two bodies.
Averaging measurements affected by instrumental uncertainty at such a great distance caused solar winds hitting Earth to appear weaker than they actually were. This created the false impression that atmospheric electric currents stabilize during massive solar storms.
Satellite data reveals escalating magnetic response
To test the traditional theory, Dr. Sivadas and Walach analyzed more than one million measurements taken by NASA satellites orbiting very close to Earth.
NASA, the United States space agency, operates numerous research satellites in low Earth orbit to monitor space weather and atmospheric conditions.
The analysis revealed a direct relationship between the strength of the solar wind and the intensity of electrical currents in the upper layers of Earth's atmosphere. The results confirm that there is no known upper limit to Earth's electrical response as solar winds grow stronger.
Risks to technology, astronauts, and power grids
Earth's magnetic field normally protects the planet by deflecting solar particles, transforming solar activity into harmless light displays known as auroras or causing minor telecommunication glitches.
Auroras, or northern lights, occur when charged particles from solar storms collide with gases in Earth's atmosphere, producing bright displays of light near polar regions.
However, severe geomagnetic disturbances carry severe hazards. Solar plasma bursts can disable satellites, corrupt GPS navigation signals, and dangerously elevate radiation levels for astronauts in space and commercial pilots flying at high altitudes.
Urgent need to update global risk models
The findings force scientists to reformulate global risk models for extreme space weather. While catastrophic geomagnetic events occur infrequently, evidence shows that space weather risks have been underestimated due to probabilistic bias.
In an increasingly interconnected world reliant on orbital technology and electrical power distribution networks, updating global prediction and defense systems against solar events has become an urgent priority.
