Free Death from the Skies! by Ph. D. Philip Plait

two-week period, Active Region 5395 blasted out nearly two hundred solar flares, a quarter of them rating in the highest energy category. At the same time, thirty-six CMEs were detected screaming out from the Sun.
    Some of the effects were merely annoyances in the grand scheme of things. A microchip manufacturer had to shut down operations temporarily because some sensitive instruments were not behaving during the magnetic upheaval. Compass readings were off by many degrees, making navigation for ships difficult. Many satellites lost altitude—by as much as half a mile—and one military satellite could not compensate for the effects, and began to tumble. Other satellites were fried as well.
    But the worst effects occurred on March 13, when a vast geomagnetically induced current was created by the storm. Voltage fluctuations caused power problems around the planet. In New Jersey, the current induced by forces far overhead blew out a power plant’s 500,000-volt transformer, which cost $10 million to replace. It took six weeks, and the company lost nearly twice that much money in lost power sales during that time.
    In Quebec, the effect was much more serious. The current surge shut down a power generator, and the sudden loss of power collapsed the grid. Transmission wires failed over a huge area, some exploding in flames. In the middle of a winter’s night, the electricity for six million people in Canada was flicked off by the Sun. It took days to get the grid fully back up. Models of the event made by engineers estimated the total damage cost at several billion dollars.
    As with asteroid impacts, there are ways to mitigate the damage done by flares and CMEs. Satellites can be designed to withstand particle and gamma-ray impacts, but at a significant cost to the manufacturer. The same is true for power grids; it would cost billions to retrofit power stations and add more power lines to accommodate another March 1989 event. 16
    Such events are rare, occurring two or three times per century. But as we make more demands on our power grids, the risk of potential damage from the Sun only increases.
    And there is yet another direct impact from solar activity. Models of the impact of the 1859 event on our atmosphere have shown that the subatomic particles accelerated in the Earth’s magnetosphere by the event would have cascaded down into the atmosphere, breaking up (what scientists call dissociating ) molecules of ozone in the upper atmosphere. Ozone is a molecule made up of three oxygen atoms (the molecule of oxygen we breathe has two atoms bound together), and is very efficient at absorbing the Sun’s ultraviolet light, protecting us from it. The amount of ozone depletion from the 1859 flare would have been relatively modest, just a few percent. However, that is enough to allow increased UV radiation to reach the Earth’s surface. The effects of this on humans are unclear because of spotty medical records from more than a century ago, but it’s possible there was a small but significant rise in skin disease in the years following the event. This increase in UV can also affect the ecosystem and food chain (see chapter 4 for more details on that than you want to know), though again the records from that time are incomplete.
    There was, however, at least one measurable effect from the 1859 event. When broken up by incoming particles, the dissociated air molecules can recombine to form other chemical compounds, including NO 2 , or nitrogen dioxide. 17 This reddish-brown gas, created high in the atmosphere, would wash down to Earth in rain and be deposited on the ground. Studies of ice cores from Greenland have shown an increase in the deposition of nitrates from that time.
    The problem is, the NO 2 can oxidize in the atmosphere to form nitric acid. When this dissolves in water droplets, acid rain can result, with terrible effects on the Earth’s ecosystem. This did not appear to be a major problem from the 1859 event, but if in