Visualizzazione archivio di giovedì, 15 febbraio AM

Daily bulletin on solar and geomagnetic activity from the SIDC

Emesso: 2018 Feb 15 1230 UTC

SIDC Forecast

Brillamenti solari

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

Geomagnetism

Active conditions expected (A>=20 or K=4)

Protoni solari

Quiet

	10cm flux	Ap
15 Feb 2018	075	015
16 Feb 2018	074	012
17 Feb 2018	073	012

Bulletin

Over the past 24 hours solar activity has been low. No significant flares have been recorded. Active Region (AR) 2699 (Mcintosh class:Dso; Mag. type:Beta) has been most active, showing considerable flux emergence and cancellation. The greater than 10MeV proton flux remained at background levels over the past 24 hours. No Earth directed Coronal Mass Ejections (CMEs) have been detected. Over the next 24 hours there is a reasonable probability that flaring activity will reach C-class levels with a small probability of M-class flares. The solar wind speed fluctuated around 310 km/s over the past 24 hours, but jumped to 350 km /s this morning with the arrival of a shock front. The total magnetic field strength has remained around 3 nT, but began fluctuating between 3 and 9 nT in the last few hours. The Bz component has fluctuated between -3 and +3 nT. Geomagnetic conditions ranged between Kp index 0-2 (NOAA) and local K index 0-2 (Dourbes) over the past 24 hours. The above mentioned shock front arrived at 07:55 UT this morning. The sudden increase in the solar wind speed (from about 310 to 350 km/s) was observed simultaneously with an increase in the density, temperature and the interplanetary magnetic field magnitude (from about 2 nT to 7 nT). Since the solar wind speed was, and is still rather low, and the Bz component of the interplanetary magnetic field was mostly positive, the shock arrival did not induce disturbed geomagnetic conditions. The shock is probably related to the CME produced at 01:25 UT on 12-Feb-2018, which was anticipated to arrive at approximately 12:00 UT today. A large coronal hole that passed the central meridian a couple of days ago may also be the cause, however the associated High Speed Stream (HSS) is expected to arrive later today / tomorrow. Enhanced solar wind conditions from the coronal hole and CME arrival are expected to cause geomagnetic conditions to be unsettled.

Today's estimated international sunspot number (ISN): 016, based on 10 stations.

Solar indices for 14 Feb 2018

Wolf number Catania	///
10cm solar flux	075
AK Chambon La Forêt	007
AK Wingst	003
Estimated Ap	003
Estimated international sunspot number	023 - Based on 22 stations

Noticeable events summary

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

Tutti gli orari in UTC

<< Vai alla pagina della panoramica giornaliera