Publié: 2017 Sep 21 1239 UTC
Quiet conditions (<50% probability of C-class flares)
Quiet (A<20 and K<4)
Quiet
| Flux de 10 cm | Ap | |
|---|---|---|
| 21 Sep 2017 | 076 | 006 |
| 22 Sep 2017 | 076 | 007 |
| 23 Sep 2017 | 079 | 016 |
Over the past 24 hours the solar activity was very low with only a few B-class flares recorded. The major flare was a B8.4-class flare at 19:32 UT attributed to the Catania sunspot group 55 (NOAA active region 2680). The returning region has been assigned a new number: Catania sunspot group 56 (NOAA active region 2681). Both regions show a simple photospheric magnetic field configuration (alpha) and are unlikely to produce any strong flaring activity. We expect the solar activity to remain low with some B-class flares and a slight chance for C-class flares.
No Earth directed CMEs have been observed and the solar protons remained at background level over the past 24 hours.
The Earth is currently inside a slow solar wind flow that has declined further from 500 to 400 Km/s. The interplanetary magnetic field magnitude remained below 6 nT and the Bz component fluctuated between -4 and 4 nT being mainly negative. A relatively small equatorial coronal hole in the south hemisphere has crossed the central meridian yesterday Sept 20 around 16:30 UT. The associated fast solar wind is expected to arrive at Earth on Sept 23 late afternoon.
Geomagnetic conditions were quiet to unsettled with Kp (NOAA) and local K (Dourbes) indexes ranging between 1-3 and 0-2 respectively. The geomagnetic conditions are expected to remain quiet to unsettled until Sept 23 when the fast solar will reach Earth.
Estimation du nombre international de taches solaires (ISN) pour aujourd'hui : 023, sur la base de 22 stations.
| Nombre de Wolf, observé par Catania | 012 |
| Flux solaire à 10 cm | 074 |
| AK Chambon La Forêt | 012 |
| AK Wingst | 012 |
| Ap estimé | 012 |
| Nombre international de taches solaires estimé | 021 - Basé sur 28 stations |
| Jour | Commencer | Max | Fin | Loc | Force | OP | 10cm | Catania/NOAA | Types de sursaut radio | |
|---|---|---|---|---|---|---|---|---|---|---|
| Aucun | ||||||||||
Données fournies par le Solar Influences Data analysis Center© - SIDC - Traité par SpaceWeatherLive
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