Solar storm from 1977 reveals how unprepared we are for the next 'big one'

Recent research reveals surprising variations in the strength of solar storms across short distances, suggesting that existing sensor networks might not sufficiently prepare us for future outbursts.

Solar storms hitting Earth can vary significantly over short spans, with areas just a few dozen miles apart experiencing vastly different magnetic disruptions, according to a new study.

This variability implies that certain regions might be more susceptible to intense solar storms than previously understood. Eija Tanskanen, the study's co-author and director of the Sodankylä Geophysical Observatory in Finland, highlighted this concern.

Current monitoring networks for solar storms mostly use sensors spaced around 250 miles apart on average. However, the study found that the strength of these storms fluctuates over much smaller distances, approximately 62 miles.

Tanskanen warned that a sparse network of sensors could lead to underestimating local magnetic disturbances during solar storms.

Solar storms occur when charged particles from the sun collide with Earth's atmosphere. While the atmosphere shields the planet, satellites in low-Earth orbit face risks of electrical surges and damage. Severe storms can also push auroras to lower latitudes and disrupt power grids.

To investigate these impacts in detail, researchers revisited a strong solar storm recorded in 1977 by 32 stations in the Scandinavian Magnetometer Array.

By digitizing and analyzing the data from this array, they discovered extreme variations in magnetic disruption from station to station, even over short distances.

During intense solar storms, the magnetic disturbance could differ by up to 150 nanotesla within about 6 miles, emphasizing the disparity in impact between nearby areas.

The study advocates for expanding the sensor network that monitors Earth's magnetic field. Tanskanen highlighted that a denser network would enhance our understanding of magnetic field complexities during solar storms, enabling better local warnings and safeguarding vulnerable infrastructure.