Viewing archive of Friday, 21 May 1999
Geophysical report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Solar and Geophysical Activity Summary 1999 May 21 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 141 Issued at 0245Z on 21 MAY 1999 This report is compiled from data received at SWO on 20 MAYA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 1913 1914 1914 660
B. Proton Events
None.
C. Geomagnetic Activity Summary
THE GEOMAGNETIC FIELD WAS QUIET TO
UNSETTLED.
D. Stratwarm
None.
E. Daily Indices: (real-time preliminary/estimated values)
10 CM 143 SSN 121 AFR/AP 010/010 X-RAY BACKGROUND B4.8 DAILY PROTON FLUENCE (FLUX ACCUMULATION OVER 24 HRS) GT 1 MEV 1.6E+05 GT 10 MEV 1.5E+04 P/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) DAILY ELECTRON FLUENCE GT 2 MEV 2.80E+07 E/(CM2-STER-DAY) (GOES-8 SATELLITE SYNCHRONOUS ORBIT W75 DEGREES) 3 HOUR K-INDICES: BOULDER 2 2 2 3 3 2 2 3 PLANETARY 2 3 2 3 3 2 1 3
F. Comments
A MODERATE INTENSITY 245 MHZ NOISE STORM WAS IN PROGRESS DURING THE PERIOD. COMMUNICATION PROBLEMS CONTINUED WHICH MAY HAVE RESULTED IN SOME MISSED RADIO AND OPTICAL REPORTS. ENERGETIC ELECTRON FLUXES BECAME ELEVATED DURING THE PERIOD BUT DID NOT REACH ALERT THRESHOLD.
All times in UTC
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