SUN ERUPTS WITH INTENSE ACTIVITY
Oct. 22, 2003 Forecasters at the NOAA Space Environment Center in
Boulder, Colo., observed two dynamic areas of the sun, one of which
has produced a coronal mass ejection, or CME, Wednesday morning at 3
a.m. EDT that appears to be Earth-directed. The forecasters are
predicting a strong geomagnetic storm, G-3 on the NOAA Space Weather
Scales, that should reach Earth on Friday, October 24. (Click here
to view larger image from the SOHO spacecraft of the intense solar
activity on the sun taken Oct. 21, 2003. Click here to view high
resolution version, which is a large file. Click here to view latest
images. Please credit "SOHO.")
NOAA Region 484 developed rapidly over the past three days and is
now one of the largest sunspot clusters to emerge during Solar Cycle
23. It is about 10 times larger than the Earth. This region, which
is nearing the center of the sun, already produced a major flare, R-
3 on the NOAA Space Weather Scales, producing a radio blackout on
October 19 at 12:50 p.m EDT. The region continues to grow, and
additional substantial flare activity is likely.
Larry Combs, a forecaster with the NOAA Space Environment Center's
Space Weather Operations, said that this region has developed
rapidly over the last three to four days. "It's somewhat unusual to
have this much activity when we're approximately three-and-a-half
years past solar maximum," he said. "In fact, just last week, solar
activity was very low with an almost spotless sun." Solar cycles of
high and low activity repeat about every eleven years, and the sun
has been moving towards solar minimum for the past three years.
A second intense active region is rotating on the southeast quadrant
of the sun. Although the sunspot group is not yet visible, two
powerful eruptions occurred on October 21 as seen from the LASCO
instrument on the SOHO spacecraft. These eruptions may herald the
arrival of another volatile active center with the potential to
impact various Earth systems.
Further major eruptions are possible from these active regions as
they rotate across the face of the sun over the next two weeks.
Satellite and other spacecraft operations, power systems, high
frequency communications, and navigation systems may experience
disruptions over this two-week period.