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Magnetic Storm Forecast Following Giant Sunspot Flare
By Randolph E. Schmid
Associated Press Writer
WASHINGTON (AP) - A magnetic storm that could disrupt
radio transmissions and satellites - and also produce colorful northern
lights - is expected to strike the earth Saturday and could last until
Monday.
The massive sunspot eruption took place early Friday, the
National Oceanic and Atmospheric Administration reported.
"The storm is expected to reach strong to severe
levels, which can adversely affect satellite operations and power
grids," reported the agency.
In addition, space weather forecasts said there is a good
chance of seeing the Aurora Saturday through Sunday morning in cities as far
south as Washington, D.C ., Seattle, New York and Denver.
NOAA's Space Environment Center in Boulder, Colorado,
reported that Friday's large complex sunspot group produced one of the
largest solar flares seen in recent years.
The solar flare, a giant eruption bursting out from the
surface of the sun, took place about 6:24 a.m. EDT, the center said.
The event ejected billions of tons of plasma and charged
particles into space, some of it heading toward Earth at 3 million miles per
hour. The mass ejection is expected to strike the Earth's magnetic
field on Saturday afternoon and cause the geomagnetic storm.
The Earth's magnetic field protects the planet from most
such charged particles, but in a strong burst such as this, some disruptions
can occur. As the field deflects the incoming particles they are moved
toward the north and south poles where they cause the northern and southern
lights, called auroras.
The NOAA scientists reported that the solar flare has
already caused some effects on Earth, including some radio blackouts.
A NASA satellite located about one million miles upstream
from Earth detects geomagnetic storms approaching Earth and provides NOAA
forecasters with a warning about one hour before they reach Earth's magnetic
field.
In 1989, a severe solar storm knocked out power stations
serving Canada and the northeastern states, as well as an electrical
transformer in New Jersey. Since then, the power grid and satellite
operations have taken steps to protect their systems.
The sun is currently in the most intense phase of its
11-year sunspot cycle.