Friday, 18 January 2013

Solar activity: geomagnetic storms expected!

January 18, 2013 - THE SUN - According to Space Weather, decaying sunspot AR1654 has a beta-gamma magnetic field that harbors energy for M-class solar flares. In addition, two Coronal Mass Ejections (CMEs) are expected to impact the earth in the next 24 hours and a G1-Class Geomagnetic storm will be possible shortly after. Solar activity is expected to go quiet again after these active regions rotate off the earth-facing disk over the next 36 hours.

CHANCE OF STORMS: NOAA forecasters estimate a 30% chance of polar geomagnetic storms today. The reason is an incoming CME, which could deliver a minor blow to Earth's magnetic field during the next 24 hours. Arctic sky watchers should be alert for auroras. - Space Weather.

SOLAR UPDATE: Solar activity is currently low with minor C-Class flares detected off the northwest limb near departed region 1652. The Earth facing side of the Sun is down to two remaining visible sunspots. Former monster 1654 is no longer a threat for strong solar flares. Solar activity is expected to continue at low levels in the short term. A brief period of minor geomagnetic activity was observed at very high latitudes on Thursday and was the result of a southward Bz component of the interplanetary magnetic field (IMF), combined with weak effects of a CME impact. - Solar Ham.

GEOPHYSICAL SUMMARY: The geomagnetic field has been at quiet to active levels for the past 24 hours. Solar wind speed, as measured by the ACE spacecraft, reached a peak speed of 456 km/s at 17/0305Z. Total IMF reached 16 nT at 17/1526Z. The maximum southward component of Bz reached -14.1 nT at 17/1448Z. Protons greater than 10 MeV at geosynchronous orbit reached a peak level of 2 pfu at 17/1415Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1135 pfu. The geomagnetic field is expected to be at minor storm levels on day one (18 Jan), active levels on day two (19 Jan), and minor storm levels again on day three (20 Jan). - NOAA/SWPC.