Viewing archive of Saturday, 11 December 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Dec 11 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 11 Dec 2021 until 13 Dec 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
11 Dec 2021077010
12 Dec 2021078011
13 Dec 2021078011

Bulletin

Solar activity was at very low levels with the X-ray flux below B-class flare over the last 24 hours. Solar activity is expected to remain at low levels.

No Earth directed CMEs has been 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 at nominal levels in the next 24 hours. The greater than 2 MeV electron flux exceeded the 1000 pfu alert threshold in the past 24 hours and may remain elevated in the next 24 hours. The greater than 2 MeV electron fluence was moderate levels in the past 24 hours and is expected to remain moderate levels in the next 24 hours.

The solar wind parameters (ACE+DSCOVR) became slightly enhanced due to the arrival of the expected perturbation associated to the high-speed streams from the small equatorial coronal hole (negative polarity, north hemisphere) that traverse the central meridian on Dec 05. The total magnetic field reached 10 nT, and its southward component, Bz, fluctuated between -8.4 nT and +6.3 nT in the past 24 hours , while the wind speed remained slow ranging between 295 km/s and 337 km/s. The solar wind parameters are expected to show some further enhancement and the increase of the wind speed. The high-speed streams associated to the other small equatorial coronal hole (negative polarity, south hemisphere, that crossed the central meridian on December 8) may also slightly enhance the solar wind parameters near Earth around December 12-13.

Geomagnetic conditions were quiet to unsettled over the past 24 hours (NOAA Kp and K-BEL recorded values 0 to 3). Geomagnetic conditions are expected to remain mostly quiet with some unsettled periods in response to the influence of the wind streams associated to the small equatorial coronal hole.

Today's estimated international sunspot number (ISN): 000, based on 16 stations.

Solar indices for 10 Dec 2021

Wolf number Catania///
10cm solar flux076
AK Chambon La Forêt009
AK Wingst003
Estimated Ap002
Estimated international sunspot number000 - Based on 15 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

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

All times in UTC

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