| During the last week, solar activity was high on 27, 31 Dec, moderate on 28-29 Dec and low for the rest of the time. Seventeen sunspot active regions (AR4312, AR4316-AR4317, AR4319-AR4332) were on the visible disk with six M-class flares produced. The F10.7 index fluctuated between 166 sfu and 195 sfu. No solar proton event occurred. Due to the effect of a recurrent coronal hole high speed stream, the solar wind speed reached the peak of about 540 km/s on 31 Dec. The geomagnetic field was at quiet to unsettled levels. The greater than 2 MeV electron flux at geosynchronous orbit reached minor storm levels on 26-30 Dec. |