Viewing archive of Monday, 24 September 2018
Daily bulletin on solar and geomagnetic activity from the SIDC
Issued: 2018 Sep 24 1230 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 | |
|---|---|---|
| 24 Sep 2018 | 067 | 006 |
| 25 Sep 2018 | 067 | 007 |
| 26 Sep 2018 | 067 | 007 |
Bulletin
Solar activity was very low with X-ray flux remaining below B level and no spots on the visible disk. This is expected to remain so over the next days.
A filament erupted around noon September 23 from the North Eastern sector but no associated CME could be identified in coronagraph images.
Proton flux levels were at background values and are expected to remain so.
Solar wind remained slightly elevated with solar wind speed around 450 km/s. Initially, total magnetic field was elevated at 7.5-10nT with the phi angle indicating connection to negative polarity photospheric magnetic field and solar wind speed declining. But just before midnight a switch into negative polarity connection came associated with a dip in total magnetic field and a renewed slight increase of solar wind speed (reaching 480 km/s). Meanwhile the phi angle has switched back into the negative sector and solar wind is again declining (currently around 430 km/s). Solar wind speed is expected to remain slightly enhanced and may possible slightly increase under the influence of some patchy negative polarity open fields in the Southern hemisphere near the equator.
Geomagnetic conditions were quiet to unsettled (NOAA Kp 2-3 and local K Dourbes 1-3) and are expected to remain so.
Today's estimated international sunspot number (ISN): 000, based on 29 stations.Solar indices for 23 Sep 2018
| Wolf number Catania | /// |
| 10cm solar flux | 068 |
| AK Chambon La Forêt | 016 |
| AK Wingst | 012 |
| Estimated Ap | 013 |
| Estimated international sunspot number | 000 - Based on 22 stations |
Noticeable events summary
| Day | Begin | Max | End | Loc | Strength | OP | 10cm | Catania/NOAA | Radio burst types | |
|---|---|---|---|---|---|---|---|---|---|---|
| None | ||||||||||
Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive
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