Viewing archive of Wednesday, 4 October 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Oct 04 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
04 Oct 2017	086	009
05 Oct 2017	085	015
06 Oct 2017	085	012

Bulletin

Solar activity was at very low levels. NOAA 2683 (Catania 57) gained some small opposite polarity sunspots south of the main spot, and was the source of 3 low-level B-class flares. NOAA 2682 (Catania 56) was quiet, showing a long filament to the east and north of the main spot. No earth-directed coronal mass ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux was at nominal levels.

Quiet flaring conditions are expected, with a small chance on a C-class flare.

A sector boundary crossing (SBC) was observed in the solar wind during the first half of 03 October, during which the interplanetary magnetic field changed its direction from "away" to "towards" the Sun. During the last 24 hours, solar wind speed declined gradually from 410 to 370 km/s (DSCOVR). Bz fluctuated between -2 and +4 nT.

The geomagnetic field was mostly quiet, with Kp at unsettled levels during the 03-06UT interval. Quiet to unsettled geomagnetic conditions are expected to continue. The arrival of the particle stream associated with a small negative equatorial coronal hole is expected late on 04 or on 05 October, and may increase the likelihood on an active geomagnetic episode.

Today's estimated international sunspot number (ISN): 027, based on 12 stations.

Solar indices for 03 Oct 2017

Wolf number Catania	///
10cm solar flux	086
AK Chambon La Forêt	009
AK Wingst	007
Estimated Ap	007
Estimated international sunspot number	028 - Based on 25 stations

Noticeable events summary

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

All times in UTC

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