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Solar Flares and Their Impact on the Earth
The Sun and Earth in Perspective
It is possible that the Sun could have a really minor tantrum and spit an insignificant portion of its mass at us and literally plunge us right back into the Dark Ages. No power; no lights; no computers, elevators, radio or television; no cars except maybe those from pre-1970 that don’t use electronics. It could all be gone in an instant; all electronics rendered useless. If it was severe enough, it could be days, months or even years before our infrastructure could be rebuilt sufficiently to be able to manufacture replacement parts for all our electrical equipment.
Why are we vulnerable?
To understand how this could occur we need to understand that the Sun is Big. In our daily lives it is just a bright shiny disk in the sky about the size of your fingernail held at arm’s-length. That’s the way we see it and how it fits into our perceptions. But for this discussion you need to come to terms with how big it really is.
I can state that it is about 875,000 miles (1,392,000 kilometers) wide, but large numbers don’t fit very well in our brains. I could tell you that in comparison the Earth is merely 8,000 miles (12,700 km) wide, but still that is further than you would want to walk, so it is too big. Since most of us have never run a marathon, even those distances are foreign to our thoughts, so let’s deal with something smaller – much smaller. A grain of sand is about 1/75 of an inch (0.038mm) on average, which is to say you would need to lay out seventy-five of them edge-to-edge to make a line one inch long (2.5cm). If you repeated that 11,666 times you would have a line 972 feet (296 meters) long where each individual grain represents one mile (1.6km), and the total length represents the diameter of the Sun. On that scale, the Earth would be 8,000 grains wide, or less than 1% of the line’s length.
This has happened before
On September 1st, 1859 the Sun ejected some mass directly at the earth. This was a major coronal mass ejection (CME), and it was pointed straight at Earth. In less than two days the storm of high energy protons and electrons arrived, and to the largely unelectrified world of 1859, it looked beautiful.
The only significant metals available to induce currents were telegraph wires, and this caused burns and shocks to some operators, and set fire to a telegraph shed. Other than that, people waxed poetic about the beauty of the Aurorae that encircled the globe; about its being brighter than the Moon; about being able to read a newspaper at night by its shimmering red, blue, green, yellow, and purple curtains of light. If the same thing happened today, it could cause trillions of dollars in damage.
In 1989, a lesser CME struck Earth and tripped the safety-system breakers for Hydro-Quebec, plunging Canada’s largest province into darkness in less than eighty seconds! It was fully nine hours before the system could be brought back online by decreasing its sensitivity to the wild fluctuations of Earth’s magnetosphere. All northern electrical grids are impacted by these events (such as northern Russia and Scandinavia); one as large as 1859 could affect most of the globe, doing untold damage.
The space shuttle Discovery was on-orbit at the time and had some mysterious electronic problems; and many of the trans-polar satellites lost communications for several hours during the event.
Late in 2003 a CME caused one of these Geomagnetic Storm events and compromised more than one third of NASA’s satellite fleet. How would we cope with losing GPS and weather satellites for years?
What protects us?
The Earth’s core is solid iron, around which swirls molten iron. This creates a magnetic field that we use with compasses to help us find our way in the world. As a nice side-benefit, this Magnetosphere extends far out into space and steers most of the solar wind safely around our planet. Around the north and south poles the fields offer less protection, and streams of high-energy particles come streaming down and excite the nitrogen and oxygen in our atmosphere. These gases start to glow, creating the Aurora Borealis in the north and Aurora Australis in the southern hemisphere.
For those living as far south as Pennsylvania or Iowa, you were treated to a bit of Aurora Borealis, if you happened to be in a dark enough spot around September 11th, 12th and 13th, 2014. There was a big CME event followed by a pair of smaller ones. It was great if you weren’t drowned in city lights, and were outside. While we are somewhat insulated from minor effects of solar misbehaviour in the United States, bear in mind that the Toronto Stock Exchange in Ontario, Canada had to call a halt to trading in August 1989 because of this type of activity. It is less than 300 miles north of the New York Stock Exchange. What would happen if the NYSE went down?
Solar Flare Video - cool!
Worst Case Scenario
Induced currents in ordinary metal objects are one thing, but in a massive event, induced currents could burn out generators, fry all electronics and leave us in a pretty desperate spot. Batteries become exhausted; solar cells would probably be destroyed like a DVD placed in a microwave oven; even a generator that wasn’t running, and possibly survived, needs fuel. How will you get the generator’s fuel out of the tanks buried in the ground?
The windings of electrical generators in Hoover Dam and Niagara Falls turbines would be melted and there would be little working industry (except blacksmiths) to rebuild metal parts or create the hundreds of miles of wire needed to make cores for the generators. What we now produce in mere hours could take decades to replicate. On top of that, we would lose the top layer of our atmosphere, and consequently our Ozone Layer… Melanoma, anyone? Let’s hope this doesn’t happen.
So why don’t you look worried?
In truth, these events are rare. We had one in 2012 that just grazed us, and they’re usually about 500 years apart for really big events. The smaller ones, although a lot more frequent, are more of an inconvenience (like losing radio communications for a few hours) than a real threat. Besides, remember that the Sun is really big. Imagine a large beach ball is the Sun, and all over the surface are tiny guys with peashooters, facing outwards. Every once in a while one of them will shoot a pea. It may be the guy on the north pole of the sun, or the guy on the back side, or that one down in the right bottom corner… These “peas” goes out in a straight line from wherever the “shooter” is standing. Now imagine from all of these billions of shooters that the one facing you is waiting for his billions-to-one chance to shoot a pea. I think he’s going to be waiting a long time.
So relax… Utilities have learned that we’re more vulnerable than we thought we were. They’re “hardening” their systems, meaning they’re making them more resistant to this sort of damage. They’re applying some of the knowledge gained from years of Cold War research to make things resistant to the Electro Magnetic Pulse (EMP) of a thermonuclear device. And, of course, we have SOHO (NASA’s Solar and Heliospheric Observatory) watching the sun constantly. It can give us about two days warning of a truly big event so we can take action like shutting down vulnerable systems, grounding planes, securing satellites or whatever is deemed necessary