Saturday, May 19, 2012

Solar Flare To Hit Earth Today From Monster Sun Spot

CAPE CANAVERAL, Florida -- An enormous sun spot named AR 1476 is producing solar flares and coronal mass ejections (CME).  The largest solar flare was a C3 class that erupted on May 17, 2012.  This solar flare's associated coronal mass ejection is expected to hit earth today on May 19, 2012.

According to the joint U.S. Air Force / NOAA report of Solar and Geophysical Activity, Earth's geomagnetic field is expected to be at quiet to unsettled levels with isolated active periods on May 19, 2012 due to a possible shock arrival from the May 17 coronal mass ejection:

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 139 Issued at 2200Z on 18 May 2012

IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity was at low levels.  The largest flare
was a C3 at 18/0823Z from old Region 1476 (N10, L=180), which
rotated off the disk.  A filament eruption was observed in SDO/AIA
304 imagery beginning at 18/0510Z near Region 1482 (N15W17).  An
associated CME was observed in STEREO A COR 2 imagery beginning at
18/0709Z with an estimated plane-of-sky speed of approximately 482
km/s.  The majority of the ejecta appeared to be slightly north of
the ecliptic plane, however a glancing blow is likely.

IB.  Solar Activity Forecast:  Solar activity is expected to be at
low levels with a slight chance for an M-class flare all three days
(19 - 21 May).

IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field was at quiet to unsettled levels.  The greater
than 100 MeV proton event at geosynchronous orbit that began at
17/0200Z, reached a maximum of 20.4 pfu at 17/0230Z and ended at
17/1725Z.  The greater than 10 MeV proton event is currently
hovering close to the 10 pfu threshold (S1).

IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to unsettled levels with isolated active
periods on day 1 (19 May) due to a possible shock arrival from the
17 May CME.  Quiet to unsettled conditions are expected on day 2 (20
May).  Mostly quiet conditions are expected on day 3 (21 May). 
There is a slight chance for shock enhancement of the greater than
10 MeV protons above 10 pfu on day 1.
III.  Event Probabilities 19 May-21 May
Class M    10/10/10
Class X    01/01/01
Proton     20/05/01
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           18 May 132
Predicted   19 May-21 May  135/135/130
90 Day Mean        18 May 115

V.  Geomagnetic A Indices
Observed Afr/Ap 17 May  005/004
Estimated Afr/Ap 18 May  008/008
Predicted Afr/Ap 19 May-21 May  009/010-008/008-006/005

VI.  Geomagnetic Activity Probabilities 19 May-21 May
A.  Middle Latitudes
Active                25/10/05
Minor storm           15/05/01
Major-severe storm    05/01/01
B.  High Latitudes
Active                30/15/10
Minor storm           20/10/05
Major-severe storm    05/01/01