Another scary crapshoot: Coronal Mass Ejection
The dice are loaded against Earth from the activity of that warm and friendly object that bestows most of the energy we use, our Sun. The worst effect of the Sun will be its roasting to death all life on earth a billion or so years hence. But that warming is nothing to worry about for the next few million years (this warming has virtually nothing to do with climate change on a scale of centuries, such as 2,000-10,000 A.D).
Short-term, the biggest wallop the Sun has in store for us is a Coronal Mass Ejection.
Just do a web search on Coronal Mass Ejection and you’ll get, along with a fascinating description and analysis, an eyeful of bad news about what CME’s could do to Earth–and what they have already done, the most dramatic recent manifestation being the 1859 “Carrington Event” (named after the astronomer who witnessed the flare accompanying the CME). In 1859, telegraph wires were jolted to a degree that knocked wireless operators off their chairs, ignited fires, and took down the entire telegraph network.
Yow! Taking down the telegraph network of 1859 in the Carrington Event is nothing to taking down the internet and much of today’s power grid in one gigantic, global seizure. The impact of such a powerful CME could be catastrophic, lasting days or weeks and costing trillions of dollars in recovery and repairs. A lot of people would die. A lot of financial records would get fried; forget your retirement account.
How the dice are loaded: the Sun is bursting with CMEs
While lesser CMEs have messed with our satellites and earthbound electronics recently, the Carrington Event was hardly the worst the sun could shoot at us. The Sun is spewing CMEs regularly all over the place, some much bigger than the Carrington, but they are distributed somewhat randomly on its surface and in time (three times a day at solar maxima, once every five days at solar minima), and from the point of view of the Sun the Earth is a very small target—a pointlike object fainter than Venus appears to us with the naked eye (although there are no known naked eyes on the Sun). Relatively pint-sized CMEs strike Earth about 30 times a year, but their effects are small and short-lived.
Thus the likelihood of a Carrington-or-worse-size CME clobbering us within the next 50 years is small. But it’s not zero. One study calculates it as probable within the next century, with a 12% chance of hitting within the next decade (New Scientist October 21-27, p. 14). Here’s one of the scariest uncertainties around, and, unlike climate change and nuclear war, we have no control over the source. Nonetheless, we might have hours or even a couple of days to prepare for its arrival, since (1) the charged particles that make it so dangerous would be preceded by a blast of ultraviolet light that takes only eight minutes to reach us, and (2) research has improved such that earlier warning signs on the Sun’s surface could predict a potential catastrophe. We can take protective measures such as shutting down power stations and isolating key servers, but shutting down the entire internet for days does not seem like an option, since we are uncertain as to the scope of damage.
Find a short summary on CMEs, their dangers, recent occurrences, and ways to cope with them here
Turns out there may be a mechanism for deflecting CMEs away from Earth altogether: place an enormous loop of conductive wire between us and the Sun. Estimated price tag: $100 billion-plus. Worth the cost? There’s another gamble riddled with uncertainty—uncertainty about when but not about if. If one will hit, next week, next year, next decade, we’re not sure, but it’s approaching certainty by 2100.
See: Big Ideas about CMEs
It’s time to start urging our legislators to take this threat seriously. And I’m not kidding.
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