Viewing archive of Wednesday, 20 September 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Sep 20 1253 UTC

SIDC Forecast

Valid from 1230 UTC, 20 Sep 2017 until 22 Sep 2017
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
20 Sep 2017073007
21 Sep 2017076007
22 Sep 2017079007

Bulletin

Over the past 24 hours the solar activity was very low, only few B-class flares have been recorded. Catania sunspot group 55 (NOAA active region 2680) is unlikely to produce any flaring activity. The returning region (Catania sunspot group 49 / NOAA active region 2676) is currently on the East solar limb and is the source region of the B-class flares. We expect the solar activity to increase with B-class flares and a small probability of C-class flare coming from this returning region.

No Earth directed CMEs have been observed and the solar protons remained at background level in the past 24 hours.

The Earth is currently inside a slow (around 500 km/s) solar wind flow. The interplanetary magnetic field magnitude remained below 5 nT and the Bz component fluctuating between -4 and 4 nT. The solar wind is expected maintain its nominal conditions over the next days.

Geomagnetic conditions were quiet to unsettled (local K Dourbes 1-3, NOAA Kp 2-3) and are expected to remain quiet over the next days.

Today's estimated international sunspot number (ISN): 017, based on 20 stations.

Solar indices for 19 Sep 2017

Wolf number Catania012
10cm solar flux071
AK Chambon La Forêt017
AK Wingst012
Estimated Ap009
Estimated international sunspot number012 - Based on 32 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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