Scientists
and engineers reassure the apocalyptically fearful that a solar
flare’s impact on Earth is affected by a complex array of
variables, and the eruptions may not necessarily have cataclysmic
effects; in addition, they’ve been preparing for this for
years, developing warning systems and plotting ways to keep power
grids and global communications on-line and to protect air traffic
from disruption.
But by the
same token, nobody is sure exactly what will happen when the sun
goes ballistic. “It’s the luck of the draw, really,”
says Paul McCurley, an engineer for the Edison Electrical Institute,
a utility industry trade group.
The last solar
maximum, a decade ago, provided a glimpse of how disruptive bad
solar weather can be. In March 1989, at radio telescope facilities
in British Columbia and Ontario, needles on recording devices
suddenly flew off the scales, and alarm buzzers sounded in a startling
cacophony. The astronomers present quickly discerned the cause:
Minutes before, 93 million miles away, the sun’s magnetic
field had unleashed a huge blast of energy toward Earth. “It
was like a solar hurricane,” Dominion Radio Astrophysical
Observatory scientist Ken Tapping opined to a Canadian newspaper.
(Some solar scientists, it should be noted, object to such alarming
metaphors, noting that solar flares don’t rip out trees or
knock down houses.)
But there
wasn’t much time for them to ponder the awe-inspiring magnitude
of the event. They hurriedly began pumping out fax and computer
messages to government agencies in Canada and the United States,
warning that within the next 36 to 48 hours, the flare’s
next phase — a gas cloud filled with excited subatomic particles
— would reach our planet.
Sure enough,
in the early morning hours of March 13, the solar storm arrived.
The Earth’s atmosphere expanded as it absorbed the heat,
buffeting satellites and knocking them out of position. Within
seconds, the sun’s surplus energy surged through power lines
across the upper Northern Hemisphere. Lights in Stockholm fluttered,
and in Toronto, burglar alarms shrieked en masse. Quebec’s
electrical system took the worst hit; throughout much of the province,
refrigerators ceased humming and clocks stopped ticking. The flare’s
bizarre effects spread even father and wider; in the South, the
U.S. Navy experienced disruptions in its communications, and on
the other side of the Atlantic, the Concorde supersonic jet was
diverted from its usual route because of the possible hazard to
passengers from the flare’s gamma and x-ray radiation.
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