A massive magnetic storm at a speed of 3,000 kilometres per second — enough to circle the Earth five times in one minute – the likes of which has not been seen in the past 150 years — almost hit earth in 2012.
But at it tore through Earth’s orbit, releasing energy equivalent to that of about a billion hydrogen bombs, good fortune prevailed on the blue planet which was placed on the other side of the sun at the time.
Had the eruption come nine days earlier, it would have hit Earth, potentially destroying our electrical grid, disabling satellites and GPS and disrupting our increasingly electronic lives wreaking havoc and “causing fireworks”.
The solar bursts would have enveloped Earth in magnetic fireworks matching the largest magnetic storm ever reported on Earth, the so-called Carrington event of 1859.
The dominant mode of communication at that time, the telegraph system, was knocked out across the United States, literally shocking telegraph operators.
According to University of California, Berkeley and Chinese researchers, Earth dodged the huge magnetic bullet from the sun on July 23, 2012.
The storm was detected by Nasa’s STEREO (Solar Terrestrial Observatory) A spacecraft.
Physicist Ying D Liu, professor at China’s State Key Laboratory of Space Weather and UC Berkeley research physicist Janet G Luhmann said “Had it hit Earth, it probably would have been like the big one in 1859, but the effect today, with our modern technologies, would have been tremendous.”
The storm, if it hit earth would have caused destruction worth $2.6 trillion worldwide.
A considerably smaller event on March 13, 1989, led to the collapse of Canada’s Hydro-Quebec power grid and a resulting loss of electricity to six million people for up to nine hours.
One reason the event was potentially so dangerous, aside from its high speed is that it produced a very long-duration magnetic field.
This orientation drives the largest magnetic storms when they hit Earth because the southward field merges violently with Earth’s northward field in a process called reconnection.
“These gnarly, twisty ropes of magnetic field from coronal mass ejections come blasting from the sun through the ambient solar system, piling up material in front of them and when this double whammy hits Earth, it skews the Earth’s magnetic field to odd directions, dumping energy all around the planet,” Luhmann said.
The goal of STEREO probing the magnetic fields of the sun and Earth is to understand how and why the sun sends out these large solar storms and to be able to predict them during the sun’s 11-year solar cycle. This event was particularly unusual because it happened during a very calm solar period.
Joe Gurman at Nasa’s Goddard Space Flight Center determined that the huge outburst resulted from at least two nearly simultaneous CMEs separated by only 10 to 15 minutes. To date, it has been unclear how extreme space weather storms form and evolve. Developing a better understanding of their causes is vital to protect modern society and its technological infrastructures.