Mysterious flashes of light lit up the sky in Mexico after the country was struck by an 8.1 magnitude earthquake on Friday. Photo: courtesy Independent

 

Mysterious flashes of light lit up the sky in Mexico after the country was struck by an 8.1 magnitude earthquake on Friday, according to Forbes.  

The earthquake has been the strongest to hit the country in 100 years, which led to more than 30 deaths and tsunami warning. 

People shared on social media the video of the strange blue and green flashes of light. 

Some studies have found that the lights are generated due to ionization of oxygen to oxygen anion. Once the ionization occurs, the ions make use of small cracks and fissures to travel through the rocks until they make their way to the atmosphere, which leads to plasma light.

On the other hand, another study reveals that an intense electric field is created due to the movement of rocks containing quartz minerals.

Some studies have suggested the lights occur when two rocks rub against one another, once the rocks are separated it causes a positive voltage spike, which on a large scale, produce earthquake lights.

In 2001, NASA scientist Friedmann Freud discovered that "if the stress level (between the rocks) is high, there are electronic loads that momentarily transform insulation rock into a semiconductor." Freud added that the electrical loads are not easy to measure, as they "move with impressive speed, as high as 300 meters per second.

In an interview with National Geographic, he stated: "In the past, people often interpreted [earthquake lights] in religious terms, and in modern times they thought of UFOs, although there is a completely rational physical explanation that we are working on." 

Interestingly, similar incidents have also occurred in the past. The Kalapana earthquake in 1975 produces auroras with white and blue hue. More recently, the phenomenon was caught on camera during the Peru earthquake in 2007.