In August 1859, the world witnessed a breathtaking astronomical event when a burst of magnetized plasma from the Sun’s upper atmosphere, known as a coronal mass ejection, unleashed an unprecedented geomagnetic solar storm. This event, famously known as the Carrington event, had global repercussions, including sparking auroras visible as far south as the Caribbean and disrupting electrical systems throughout Europe and North America. What makes this historical event significant is its potential to disrupt our modern infrastructure, including the Internet. In this article, we explore the possibility of a solar storm causing an “internet apocalypse” and its implications for the digital world.
The Carrington Event: An Explosive Solar Outburst
Richard Carrington, an amateur astronomer in 1859, unknowingly observed a major coronal mass ejection from the Sun. This burst of energy, equivalent to an estimated 10 billion megatons of TNT, resulted in a geomagnetic storm that caused widespread disturbances on Earth. The rapid journey of the ejected plasma from the Sun to Earth, just 17.5 hours, was remarkable. It induced stunning auroras, disrupted electrical systems, and even led to spontaneous fires in major cities. This historic event, known as the Carrington event, serves as a reference point for understanding the potential impact of future solar storms.
The Sun operates on an 11-year solar cycle, during which its magnetic field completely reverses. These cycles can vary in duration, and their intensity fluctuates. Solar activity during these cycles includes phenomena like solar flares, sunspots, and coronal mass ejections. Solar flares and coronal mass ejections, in particular, result from the reconfiguration of highly twisted magnetic field structures in the Sun’s lower corona, a process known as magnetic reconnection.
When this reconnection occurs, it can trigger the sudden release of electromagnetic energy and the expulsion of plasma from the Sun’s surface. These events typically originate from areas with strong magnetic fields, often associated with sunspots. As the Sun progresses through its solar cycle, the frequency and intensity of these events vary.
The Potential for a Modern-Day Carrington Event
While it is fascinating to revisit the Carrington event and the science behind solar storms, the real question is whether a similar event could disrupt our digital infrastructure, including the internet. A solar storm, such as the Carrington event, can cause a large-scale demonstration of Faraday’s law, which states that a varying magnetic field induces a change in the local electric field. As the charged plasma from a solar storm approaches Earth, it distorts and weakens Earth’s magnetic field.
Most electrical systems are grounded to the Earth, providing a path of least resistance for electrical currents in case of a failure. When the geoelectric field of the Earth changes due to a solar storm, it can enter electrical systems through grounding points, inducing high voltages that can short-circuit or destroy electronic components.
The Impact on Undersea Cables
One of the most critical aspects to consider in the event of a powerful solar storm is the impact on undersea cables that carry a substantial portion of the world’s internet traffic. While optical fibers carry data as light, undersea cables also contain copper electrical lines that power repeaters, boosting the signals in optical fibers. In theory, optical fibers should be unaffected by solar storms, as they carry data as light, not electrical currents.
However, copper lines within these cables could be vulnerable to voltage fluctuations caused by a solar storm. Research by Google has shown the voltage effects of solar activity on undersea cables, with the March 1989 storm that disrupted Quebec’s electrical grid falling within the available voltage headroom before damaging these systems.
The Overdue Solar Storm Threat and Solar Cycle 25
Solar storms of different magnitudes occur irregularly. While Carrington-level events are estimated to happen once every 100 years, more powerful events that could severely affect undersea cables might occur only once per millennium. As we move toward Solar Cycle 25, we may be in a period of relative solar calm. Solar cycles vary in intensity, and the last few cycles have been relatively tame. However, the Sun’s behavior can be unpredictable, and even a seemingly mild solar cycle can produce unexpected events. As we consider the potential for a modern internet apocalypse, it’s essential to remain vigilant and prepared for the unexpected.
The Carrington event of 1859 stands as a remarkable example of the Sun’s potential to disrupt life on Earth through geomagnetic storms. While the impact of solar storms on optical fibers is minimal, the presence of copper lines in undersea cables could make them vulnerable to voltage fluctuations. The potential for a solar storm-induced “internet apocalypse” raises concerns about the digital age’s dependence on a stable internet infrastructure. As Solar Cycle 25 progresses, the need for preparedness and vigilance becomes apparent.
While the likelihood of a Carrington-level event occurring during this cycle may be relatively low, the consequences of such an event are too significant to ignore. Understanding the science of solar storms and their potential effects on our digital world is a crucial step toward safeguarding our technological infrastructure.