WASHINGTON (AP) — The sun is bombarding Earth with radiation
from the biggest solar storm in more than six years with more to come
from the fast-moving eruption.
The solar flare occurred at about
11 p.m. EST Sunday and will hit Earth with three different effects at
three different times. The biggest issue is radiation, according to the
National Oceanic and Atmospheric Administration's Space Weather
Prediction Center in Colorado.
The radiation is mostly a concern
for satellite disruptions and astronauts in space. It can cause
communication problems for polar-traveling airplanes, said space weather
center physicist Doug Biesecker.
[Related: Northern Lights dance over England]
Radiation
from Sunday's flare arrived at Earth an hour later and will likely
continue through Wednesday. Levels are considered strong but other
storms have been more severe. There are two higher levels of radiation
on NOAA's storm scale — severe and extreme — Biesecker said. Still, this
storm is the strongest for radiation since May 2005.
The radiation — in the form of protons — came flying out of the sun at 93 million miles per hour.
"The
whole volume of space between here and Jupiter is just filled with
protons and you just don't get rid of them like that," Biesecker said.
That's why the effects will stick around for a couple days.
NASA's
flight surgeons and solar experts examined the solar flare's expected
effects and decided that the six astronauts on the International Space
Station do not have to do anything to protect themselves from the
radiation, spokesman Rob Navias said.
A solar eruption is
followed by a one-two-three punch, said Antti Pulkkinen, a physicist at
NASA's Goddard Space Flight Center in Maryland and Catholic University.
First comes electromagnetic radiation, followed by radiation in the form of protons.
Then,
finally the coronal mass ejection — that's the plasma from the sun
itself — hits. Usually that travels at about 1 or 2 million miles per
hour, but this storm is particularly speedy and is shooting out at 4
million miles per hour, Biesecker said.
It's the plasma that
causes much of the noticeable problems on Earth, such as electrical grid
outages. In 1989, a solar storm caused a massive blackout in Quebec. It
can also pull the northern lights further south.
But this
coronal mass ejection seems likely to be only moderate, with a chance
for becoming strong, Biesecker said. The worst of the storm is likely to
go north of Earth.
And unlike last October, when a freak solar
storm caused auroras to be seen as far south as Alabama, the northern
lights aren't likely to dip too far south this time, Biesecker said.
Parts of New England, upstate New York, northern Michigan, Montana and
the Pacific Northwest could see an aurora but not until Tuesday evening,
he said.
For the past several years the sun had been quiet,
almost too quiet. Part of that was the normal calm part of the sun's
11-year cycle of activity. Last year, scientists started to speculate
that the sun was going into an unusually quiet cycle that seems to
happen maybe once a century or so.
Now that super-quiet cycle doesn't seem as likely, Biesecker said.
Scientists watching the sun with a new NASA satellite launched in 2010 — during the sun's quiet period — are excited.
"We haven't had anything like this for a number of years," Pulkkinen said. "It's kind of special."
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NOAA's Space Weather Prediction Center: http://www.swpc.noaa.gov/
NASA's Solar Dynamics Observatory: http://sdo.gsfc.nasa.gov
