Viewing archive of Saturday, 21 April 2001
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 2001 Apr 21 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 111 Issued at 0245Z on 21 Apr 2001 This report is compiled from data received at SWO on 20 AprA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0345 0345 0345 170 0501 0523 0543 9433 N16E63 M1.0 1f 1951 2004 2016 9433 N15E55 M4.1 1f 70 2128 2134 2140 C8.0 180 79
B. Proton Events
None
C. Geomagnetic Activity Summary
The geomagnetic field was quiet to
unsettled. The greater than 10 MeV proton event dropped below the 10
pfu event threshold at 20/1015 UTC (start 18/0315 UTC and 321 pfu
peak at 18/1045 UTC) and continues to slowly decay.
D. Stratwarm
None
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 180 SSN 103 Afr/Ap 009/008 X-ray Background B5.4 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 5.8e+06 GT 10 MeV 7.0e+05 p/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) Daily Electron Fluence GT 2 MeV 1.10e+06 e/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 3 3 1 2 2 3 3 2 Planetary 3 3 1 2 2 3 2 2
F. Comments
None
All times in UTC
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