It wasn’t some crazed dictator with his finger on the thermonuclear button or a giant asteroid that came close to wiping out civilization as we know it, though – no, what nearly ended us was a massive solar storm.
In this case, the solar storm of July 2012 consisted of a massive solar flare, followed by a colossal coronal mass ejection.
A solar flare is initiated by the sudden release of energy stored in the Sun’s corona, causing the Sun’s plasma to heat up to tens of millions of degrees, accelerating and kicking out all sorts of radiation, and often creating a solar prominence or filament.
In a large solar storm, the same energy from the corona can also cause a coronal mass ejection – a much slower-moving billion-ton cloud of plasma. The image at the top of the story, of a solar flare with the Earth photoshopped in for scale, was captured by NASA’s newer Solar Dynamics Observatory. If the solar storm had hit Earth back in 2012, the total economic impact is estimated to be around $2 trillion, or 20 times the cost of Hurricane Katrina.
If a giant solar storm hit the Earth, large parts of society could be without power for months or years.