NOAA Magazine NOAA Home Page

SUN STARTS BUBBLING

July 16, 2002 — After a long quiet period, the sun bounced back with an explosive solar flare which occurred at 4:08 p.m. EDT on Monday, July 15, according to forecasters at NOAA's Space Environment Center in Boulder, Colo. Solar flares are classified by their peak x-ray intensity, and this event was classified as an X-3, which is considered to be a strong event. (Click image from the NASA/European Space Agency SOHO satellite for larger view.)

X-flares are the highest category of flares possible and are usually measured on a scale from 1 to 20. They correspond with an R3 on NOAA's Space Weather Scales and could temporarily cause high frequency radio blackouts and degrade low-frequency navigation signals.

Forecasters say the region on the sun that produced this flare has the potential to produce additional major solar flares with coronal mass ejections as it moves across the sun's disk. "We're watching this region carefully as it has the power to grow," says forecaster Norm Cohen. This region will remain visible on the sun until it departs the visible disk early on July 23.

According to Cohen, "The active region continues to grow. It's a very complex, dynamic region with more than 90 sun spots." NOAA's Space Environment Center is forecasting a minor to moderate geomagnetic storm (G1-G-2), which could affect power systems at high latitudes. The geomagnetic storm should reach Earth sometime Wednesday morning between 4 a.m. and 10 a.m. EDT. The aurora borealis, or northern lights, may be visible in the northern tier of states in the U.S. during that time period.

Relevant Web Sites
NOAA's Space Environment Center — Click "Space Weather Now" for the latest information on solar activity.

NOAA's Space Weather Scales

NOAA Space Weather Advisories

Today's Space Weather Forecast — Includes the latest image of the sun from Earth-based telescopes positioned around the world.

Real-time images of the Sun from NASA's SOHO Satellite

Media Contact:
Barbara McGehan, NOAA Space Environment Center, Boulder, Colo., (303) 497-6288 or Jana Goldman, NOAA Research, (301) 713-2483

 

-end-