Solar Flares Could Cause Train Delays Due to Signal Failures, Crippling Railway System in UK

Just recently, it was predicted that the Earth could be in the firing line of a solar storm as Sunspot AR3513 shows the potential of emitting solar flares. This means that there is a chance that an M-class solar outburst may be hurled out and hit the Earth soon.

It is widely known that space weather can damage the electronic systems on Earth, prompting experts to focus on protecting data centers or power grids. However, a group of British scientists also warn rail chiefs to consider the risks posed by solar storms or geomagnetic storms.

What are Solar Storms?

The Earth and other planets in the Solar System are constantly exposed to charged particles shed from the Sun's outermost atmosphere. Also known as the solar wind, this stream of protons and electrons can travel from 250 miles (400 kilometers) per second to 500 miles (800 kilometers) per second.

As the solar wind reaches our planet, it sends charged particles into the magnetosphere and along the Earth's magnetic fields. This interaction causes the gas in our atmosphere to glow, creating numerous displays of northern lights.

Aside from the constant solar wind streams, the Sun can emit massive amounts of those charged particles in an event known as coronal mass ejections (CMEs). It can trigger a geomagnetic storm or the disturbance of Earth's magnetosphere due to sudden strong changes in the solar wind's density, speed, and magnetic properties.

Train Services Mayhem

Solar storms can negatively affect satellite technology, causing damage to telecommunication networks and power grids. However, it also seems that the impact can be felt a little closer to home, interfering with electricity supply and transmission systems.

The rail service in the UK is often the brunt of jokes due to delayed or cancelled services caused by the wrong type of train or leaves laying on the tracks the wrong way. In a new study, scientists at the University of Lancaster revealed that even minor solar storms can cause train signals to be triggered incorrectly and cause disastrous consequences. Led by Professor Jim Wild from the University of Lancaster and researcher Cameron Patterson, the experts modelled the flow of geomagnetically induced currents (GICs) in rail systems, focusing on the way they flow through the track circuits powered by overhead lines.

Rail systems use red and green lights to signal the drivers whether to stop or go. These light signals are powered by electrical circuits found between the rails.

The team modelled two routes, the Glasgow to Edinburgh line and the West Coast Main line, to determine if solar wind can induce GICs leading to signal failures. They discovered that induced currents from solar wind can flip a signal in either direction, switching the green light to the red or the red light to the green.

Further research involving more extreme space weather events discovered that solar storms can cause multiple signal changes across a route, in various directions, and based on the number of trains on the track. Since the effect of solar winds largely depends on latitude, the UK-based research suggests that space weather events can be strong enough to trigger signal failures every few decades.

Check out more news and information on Solar Wind in Science Times.