Viewing archive of Friday, 27 January 2012

Solar activity 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.
Report of Solar-Geophysical Activity 2012 Jan 27 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 027 Issued at 2200Z on 27 Jan 2012

IA. Analysis of Solar Active Regions and Activity from 26-2100Z to 27-2100Z

Solar activity was high. Region 1402 (N29W88) produced an X1/1f flare at 27/1837Z with associated Type II (est. speed 1523 km/s) and Type IV Radio Sweeps, along with an 810 pfu Tenflare. An associated CME was first visible in SOHO/LASCO C2 imagery at 27/1827Z. The majority of the ejecta is directed towards the STEREO A spacecraft, however, further analysis is necessary to determine potential geoeffectiveness.
IB. Solar Activity Forecast
Solar activity is expected to be low on day one (28 January) with a chance for isolated M-class activity as Region 1402 rotates around the west limb. Activity is expected to be very low to low on days two and three (29-30 January).
IIA. Geophysical Activity Summary 26-2100Z to 27-2100Z
The geomagnetic field was quiet to unsettled with isolated active periods observed at mid-latitudes and an isolated minor storm period observed at high latitudes. The increase in activity is due to the arrival of a recurrent coronal hole high speed stream (CH HSS). The greater than 10 MeV and greater than 100 MeV proton flux at geosynchronous orbit were above event threshold during the period due to the X1 flare mentioned above. The greater than 10 MeV proton event, which began at 27/1905Z and reached 96 pfu at the time of this writing, is still in progress. The greater than 100 MeV proton event, which began at 27/1900Z and reached 11 pfu at the time of this writing, is also still in progress. The Penticton 10.7 cm flux value was enhanced due to the X1 flare mentioned above. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be quiet to unsettled on day one (28 January) due to continued effects from the CH HSS. Mostly quiet conditions are expected for days two and three (29-30 January). The greater than 10 MeV and 100 MeV proton events are expected to continue on day one. A more reliable end time will be possible once the peak levels are observed.
III. Event Probabilities 28 Jan to 30 Jan
Class M25%01%01%
Class X05%01%01%
IV. Penticton 10.7 cm Flux
  Observed       27 Jan 142
  Predicted   28 Jan-30 Jan  120/120/120
  90 Day Mean        27 Jan 144
V. Geomagnetic A Indices
  Observed Afr/Ap 26 Jan  005/006
  Estimated     Afr/Ap 27 Jan  007/008
  Predicted    Afr/Ap 28 Jan-30 Jan  007/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 28 Jan to 30 Jan
A. Middle Latitudes
Minor storm10%01%01%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm15%01%01%
Major-severe storm05%01%01%

All times in UTC

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