Viewing archive of Tuesday, 31 May 2011
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 2011 May 31 0245 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Solar and Geophysical Activity Summary
SGAS Number 151 Issued at 0245Z on 31 May 2011 This report is compiled from data received at SWO on 30 MayA. Energetic Events
Begin Max End Rgn Loc Xray Op 245MHz 10cm Sweep 0247 0252 0255 1224 C3.2 26 0559 0605 0607 1226 S23E51 C7.0 Sn 100 86 1048 1101 1122 1227 S18E60 C2.8 Sn II
B. Proton Events
None
C. Geomagnetic Activity Summary
The geomagnetic field was quiet to
active during the past 24 hours.
D. Stratwarm
Not available
E. Daily Indices: (real-time preliminary/estimated values)
10 cm 112 SSN 105 Afr/Ap 007/009 X-ray Background B4.5 Daily Proton Fluence (flux accumulation over 24 hrs) GT 1 MeV 7.3e+05 GT 10 MeV 1.2e+04 p/(cm2-ster-day) (GOES-13 satellite synchronous orbit W75 degrees) Daily Electron Fluence GT 2 MeV 6.80e+08 e/(cm2-ster-day) (GOES-13 satellite synchronous orbit W75 degrees) 3 Hour K-indices Boulder 2 2 2 4 2 2 2 2 Planetary 3 2 1 3 2 2 2 3
F. Comments
The greater than 2 MeV electron fluence at geosynchronous orbit was at high levels.
All times in UTC
Latest news
Sunday, 1 February 2026
Complex sunspot region 4366
Monday, 19 January 2026
CME impact! S4 solar radiation storm
Sunday, 18 January 2026
X1.9 solar flare with earth-directed CME
Latest forum messages
Yes, we really went to the moon before. 6Do the high-resolution sunspot counts point to more complex sunspots? 64AR4366 1029Feb 8-9 CMEs 28Current Farside Activity 374
More topicsSupport SpaceWeatherLive.com!
A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!
Space weather facts
| Last X-flare | 2026/02/04 | X4.3 |
| Last M-flare | 2026/02/12 | M1.4 |
| Last geomagnetic storm | 2026/02/05 | Kp5+ (G1) |
| Spotless days | |
|---|---|
| Last spotless day | 2022/06/08 |
| Monthly mean Sunspot Number | |
|---|---|
| January 2026 | 112.6 -11.4 |
| February 2026 | 125.3 +12.7 |
| Last 30 days | 130.4 +32.7 |