Viewing archive of Monday, 11 January 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Jan 11 1232 UTC

SIDC Forecast

Solar flares

Quiet conditions (<50% probability of C-class flares)

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
11 Jan 2021	072	010
12 Jan 2021	072	006
13 Jan 2021	072	005

Bulletin

Solar activity was at very low levels on a spotless solar disk. No significant flares were detected in the last 24 hours and none are expected in the next 24 hours. No Earth-directed coronal mass ejections (CMEs) were detected in the available coronagraph imagery.

The greater than 10 MeV proton flux was at nominal levels in the past 24 hours and is expected to remain so in the next 24 hours. The greater than 2MeV electron flux remained under the 1000 pfu threshold and is expected to remain so. The 24h electron fluence was at nominal levels and is expected to remain so.

A fast-forward shock with small velocity and magnetic field increase was observed in the solar wind data (ACE and DSCOVR) at 8:25 UT on Jan 11th. The source for the shock is currently under investigation and will be clarified as more data arrives. It could be related to the arrival of the north-west CME ejected from the Sun on Jan 6th or the south-west CME associated with a filament eruption on Jan 8th. Over the past 24 hours the solar wind speed increased from about 270 km/s to presently above 360 km/s, remaining within the typical range for slow solar wind. The total magnetic field varied between 1.7 and 12 nT with Bz component in the range of -6.7 and +4.6 nT. The interplanetary magnetic field (as measured by the phi angle) was predominantly in the negative sector, directed towards the Sun, with a very short interval in the positive polarity sector.

Geomagnetic activity was overall quiet over the past 24 hours with a single locally unsettled period at 12 UTC resulting from the arrival of the shock wave earlier this morning. Quiet to unsettled geomagnetic conditions are expected within the next 24 hours with a possibility for isolated active periods caused by the enhancements in the solar wind data related to the observed shock wave and the expected high speed stream.

Today's estimated international sunspot number (ISN): 000, based on 09 stations.

Solar indices for 10 Jan 2021

Wolf number Catania	///
10cm solar flux	073
AK Chambon La Forêt	009
AK Wingst	///
Estimated Ap	004
Estimated international sunspot number	000 - Based on 19 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

<< Go to daily overview page