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NASA, NOAA GAIN
UNPRECEDENTED VIEW OF ANGRY SOLAR CYCLE
As the Sun's stormy season
approaches its zenith, solar scientists have the best seat in
the house, using the largest coordinated fleet of spacecraft
and ground observatories ever assembled to observe these angry
outbursts of solar radiation and predict the impact of
turbulent space weather.
According to scientists from
NASA and NOAA, the Sun is near the peak of its 11-year cycle
of activity. Solar maximum is the two-to-three year period
around that peak when the Sun's activity is most tempestuous
and the Earth is buffeted with powerful solar gusts.
"This is a unique solar
maximum in history," said Dr. George Withbroe, Science
Director for NASA's Sun-Earth Connection Program. "The
images and data are beyond the wildest expectations of the
astronomers of a generation ago."
By combining sophisticated new
instruments and time-tested older ones, researchers believe
their predictions and warnings related to space weather events
are becoming more accurate and timely. "The new results
from space feed directly into NOAA's plans and programs for
forecasting space weather and its effects on Earth and
technological systems," said Dr. Ernest Hildner, director
of NOAA's Space Environment Center in Boulder, CO.
The coordinated use of NASA and
NOAA technology was key in tracking and predicting the
development of an intense solar storm nicknamed the
"Bastille Day event." With data from ground-based
observatories, the Solar and Heliospheric Observatory (SOHO--a
joint project of the European Space Agency and NASA) and
NOAA's Geostationary Operational Environmental Satellites,
scientists were able to anticipate a bright solar flare and
ensuing energetic proton shower July 13.
The flare coincided with a
coronal mass ejection (CME) which sent billions of tons of
plasma into space traveling at 4 million miles per hour, two
times faster than normal.
NOAA forecasters, using data
from the Advanced Composition Explorer (ACE), typically can
provide about one hour notice of prospective magnitude before
the start of a geomagnetic storm. But the July solar shower
blinded key ACE detectors. Without reliable data, scientists
and forecasters had to wait until Earth's magnetic field
became distorted before they knew that the disturbance had
arrived.
A G5 geomagnetic storm – the
most intense classification – raged for nearly nine hours
after the solar shower's impact.
The effects of the July storm
were widespread. Cameras and star-tracking navigation devices
on several satellites were flooded with solar particles.
Measurements from particle detectors and other instruments on
several NOAA and NASA spacecraft were either degraded or
temporarily shut down. The Japanese Advanced Satellite for
Cosmology and Astrophysics (ASCA) was sent tumbling in orbit.
On the ground, aurora light
shows were seen as far south as El Paso, TX. Power companies
suffered geomagnetically induced currents that tripped
capacitors and damaged at least one transformer. Global
positioning system (GPS) accuracy was degraded for several
hours. "The July event was a surprise to some of our
customers," Hildner said. "They haven't seen this
kind of activity for nearly a decade."
A number of International
missions provided extensive data and images showing the
development and character of the July event. "The next
generation of solar missions will complement and improve upon
what scientists are learning from the existing fleet, Withbroe
said. "This will provide us with even more capability to
understand and ultimately predict solar weather and its effect
on Earth."
For additional information on
the Internet, visit:
http://www.gsfc.nasa.gov/GSFC/SpaceSci/sunearth/solarmax.htm
http://www.sec.noaa.gov/sec.html
MEDIA
CONTACT LIST
Dolores
Beasley/Space Science PIO/NASA Headquarters
(202)
358 1753
Jana Goldman/NOAA PIO/NOAA Headquarters
(301) 713 2483, ext. 181
Susan Hendrix/SEC PIO/Goddard Space Flight Center
(301) 286 7745
Michael
Carlowicz/ISTP Science Writer/Goddard Space Flight Center
(301) 286 6353
Bill
Steigerwald/Technical Writer/Goddard Space Flight Center
(301) 286 5017
Wade Sisler/Executive Video Producer/Goddard Space Flight
Center
(301) 286 6256
Rachel Weintraub/Associate Video Producer/Goddard Space
Flight Center
(301) 286 0918
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