Massive Solar Storm Distorted GPS Signals Across US by 33 Feet
A powerful solar storm in November 2025 caused unprecedented GPS disruptions across the U.S., with signals deviating by up to 33 feet. Scientists are studying the event to improve space weather predictions.
A massive solar storm in November 2025 caused widespread disruptions to GPS signals across the continental United States, with accuracy degrading by as much as 10 meters (33 feet) in some areas. Scientists, led by space physicist Endawoke Yizengaw of The Aerospace Corporation, have identified this phenomenon as unprecedented in scale, highlighting the vulnerability of modern technology to extreme space weather events.
The storm, characterized by intense eruptions of solar material impacting Earth's magnetosphere, produced spectacular auroras visible at unusually low latitudes. However, the same event also led to significant technological disturbances. Researchers analyzing data from the event discovered widespread, coast-to-coast atmospheric disturbances in the ionosphere, the region through which GPS signals travel. These disturbances created density fluctuations that distorted and diffracted the radio signals, a phenomenon known as amplitude scintillation. While scintillation is common near the poles and equator, its severe manifestation across the mid-latitudes of the U.S. was unexpected.
Unprecedented Ionospheric Irregularities Observed
Scientists pieced together the events using data from multiple instruments, including aurora cameras and ground-based Global Navigation Satellite System (GNSS) receivers across North America. They observed a vast band of enhanced electron density stretching from east to west across the ionosphere. Sharp changes in electron density along this band created conditions conducive to smaller-scale irregularities. These irregularities were detected across a wide swath of the continental U.S., from approximately 80 to 120 degrees west longitude, with some measurements indicating the disturbance extended nearly from coast to coast. The intensity of these irregularities correlated with the auroral activity, with GPS accuracy deteriorating as the aurora brightened.
Previous instances of amplitude scintillation at mid-latitudes have been limited and largely confined to individual locations. The November 2025 event, however, marked the first time such strong scintillation spanning such a vast longitudinal range was documented. The resulting horizontal positioning errors, exceeding 10 meters in some regions, pose significant risks to technologies reliant on precise navigation. For comparison, errors of just one to two meters can severely impact applications like autonomous vehicles and precision agriculture equipment.
The impact of solar outbursts on technology is a known concern. Solar flares can disrupt high-frequency radio communications, while more significant solar storms, involving coronal mass ejections, can generate electrical currents that affect power grids and alter the atmosphere. The specific effect studied by Yizengaw's team involves energetic particles from geomagnetic storms raining down into the ionosphere, causing the density fluctuations that distort GPS signals.
While the November 2025 storm's economic impact was likely less severe than the May 2024 solar storm's estimated $500 million cost to the U.S. agricultural industry (due to timing – the 2024 storm occurred during peak farming season), the two events underscore the vulnerability of critical sectors to the Sun's solar activity, especially during the peak of its 11-year cycle. Researchers emphasize that better understanding and prediction of how extreme solar events influence the ionosphere are crucial for mitigating future disruptions to radio-frequency applications, including navigation and communication systems.
"The results underscore the importance of accurate understanding of various space weather phenomena to enhance our predictive capabilities through coordinated observations and physics‐based modeling and ultimately reducing disruptions to RF applications during space weather events," the scientists wrote in their paper published in Geophysical Research Letters. They added that if the November storm had coincided with the agricultural season, it could have resulted in substantial economic losses for American farming and transportation industries, highlighting the need to characterize storm-time irregularities and their causes.