Blackouts, Burnouts,
and Bummers
Aside from bright auroras, there are other less benevolent effects of
the connection between Sun and Earth. In fact, bright auroras are
merely a visible sign that the balance of electrical and magnetic
energy in Earth's magnetosphere has been upset. With the average
CME dumping about 1500 Gigawatts of electricity into the atmosphere
(double the power generating capacity of the entire United States),
big changes can occur in our space. Those changes can wreak havoc
on a world that has come to depend on satellites, electrical
power, and radio communication-all of which are affected by electric
and magnetic forces. For the satellites dancing in and out of the
radiation belts and the solar wind, CMEs and magnetic storms can be
perilous. For instance, a series of flares and coronal mass ejections
in March 1989 produced a potent magnetic storm. After the particles
and energy from the Sun bombarded the Earth, more than 1500
satellites slowed down or dropped several miles of altitude in their
orbits due to increased drag.
But atmospheric drag isn't the only effect CMEs can have on
satellites. When excited and accelerated by a storm, high-energy
electrons can degrade the solar panels used to power satellites
and can upset and even shut off computers on a spacecraft. The
increased flow of electricity in Earth's space also can cause
electrical charge build up on the surface of a spacecraft. That
charge can eventually be released as a damaging spark (a spark not
unlike the one you get when you touch metal or a friend after you
drag your feet on a carpet). In 1994, two Canadian satellites were
shut down when each was electrically shocked during magnetic
storms; as a result, telephone service across Canada was disrupted
for months. Similarly, in January 1997, an American satellite went
dead just hours after a CME struck the magnetosphere. The loss of
that satellite disrupted television signals, telephone calls, and
part of a U.S. earthquake monitoring network.
Magnetic storms also play havoc with radio signals, which are
bounced off Earth's ionosphere (the outermost layer of our
atmosphere, made up mostly of plasma) as a sort of natural relay
station. In March 1989, listeners in Minnesota reported that
they could not hear their local radio stations, but they could
hear the broadcasts of the California Highway Patrol. In the
extreme, magnetic storms can completely wipe out radio communication
around Earth's North and South Poles for hours to days.
On the ground, magnetic storms can affect the strength of Earth's
magnetic fields. Changes in magnetic fields can produce surges in
power lines and strong electrical currents in gas and oil pipelines.
The extra current can cause pipelines to corrode and deteriorate
faster than they would naturally; in power lines, the extra
electricity can burn out transformers and cause brownouts and
blackouts. During the March 1989 storm, a transformer burned up
at a power plant in New Jersey, and a whole system was blown out
at a power station in Quebec, leaving 6 million people without
electricity for hours, some for months. Since so much modern
information is relayed by satellites and other advanced
technology-from automated teller machines and broadcast signals
to the Global Positioning System and disaster warning systems-CMEs
pose a natural and technological hazard to life on Earth.
NEXT PANEL: Make Your Own Sun-Earth
Connections
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