Viewing archive of Thursday, 18 April 2002
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 2002 Apr 18 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 108 Issued at 0245Z on 18 Apr 2002 This report is compiled from data received at SWO on 17 AprA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0746 0824 0957 9906 S14W34 M2.6 2n 890 3000 II/IV 1008 1016 1114 150 230 1413 1413 1413 290 1559 1559 1559 150 1643 1643 1643 100 1912 1912 1913 210 1932 1933 1933 210 2010 2010 2011 2400 2125 2126 2126 140
B. Proton Events
A greater than 10 MeV proton event began at
17/1530 UTC. The maximum flux observed so far was 24 pfu at 17/1540
UTC. This event remains in progress.
C. Geomagnetic Activity Summary
The geomagnetic field ranged from
quiet to major storm levels. A shock was observed at the NASA ACE
spacecraft at 17/1022 UTC and was followed by an SI at ground
magnetometers at 17/1109 UTC (57 nT at Boulder). This shock is
believed to be associated with the LDE M1/CME which occurred on 15
April.
D. Stratwarm
None
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 194 SSN 137 Afr/Ap 031/041 X-ray Background C1.0 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 1.9e+07 GT 10 MeV 4.7e+05 p/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) Daily Electron Fluence GT 2 MeV 6.50e+05 e/(cm2-ster-day) (GOES-8 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 2 3 3 5 5 6 4 3 Planetary 2 3 2 6 6 6 5 3
F. Comments
The 17 April Afr index reported in Part E is estimated from Boulder observations.
All times in UTC
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