Affichage des archives de mercredi, 24 septembre 2014

Bulletin quotidien sur l'activité solaire et géomagnétique du SIDC

Publié: 2014 Sep 24 1232 UTC

Prévisions SIDC

Éruptions solaires

Eruptive (C-class flares expected, probability >=50%)

Géomagnétisme

Quiet (A<20 and K<4)

Moniteur de Flux de Proton

Quiet

	Flux de 10 cm	Ap
24 Sep 2014	142	016
25 Sep 2014	146	011
26 Sep 2014	150	010

Bulletin

Solar flaring activity has been moderate. An isolated M2.3 flare was produced by NOAA AR 2172 peaking at 23:16 UT. It was associated with a dimming as well as type II radio burst detections (Learmonth estimated shock speed 790-1250 km/s). A corresponding CME observed by STEREO B COR2 departing the west limb (as seen from STEREO B) does not appear to be fast nor very wide. SOHO/LASCO data for the relevant time slot just became available and records the CME in C2 data from midnight onwards. This imagery confirms the small angular width (roughly about 120 degrees) and indicates a primary direction towards the east. With the small recorded speeds (plane of the sky projected speed around 300 km/s) even a glancing blow seems unlikely. With background Xray flux around the B6 level and NOAA AR 2171 the only significant potential flaring source we expect flaring at C-level although their is a fair chance for another M flare from this region as it continues to evolve and grow in size. Another asymmetric halo CME was detected with first appearance in SOHO/LASCO coronagraph images at 19:00 UT, for which Cactus has sent out a corresponding alert. Despite a data gap in STEREO B EUVI 193 data between 18:16UT and 21:26 UT the start of the eruption (from the same active region as the previous two partial/asymmetric halo CME's) was recorded just before the data gap, as well as the post flare loops just after the data gap. The event is thus judged to be backsided. Solar wind speed dropped further during the first half of the reporting period to a minimum of close to 370 km/s around 19:00 UT. It increased afterwards to around 420 km/s presently. The total magnetic field slightly increased to above the 7 nT level with periods of Bt 8nT and negative BZ around -7nT. Unsettled to active geomagnetic conditions have been recorded (NOAA Kp 3-4, local hourly K Dourbes 1-4). Similar solar wind conditions and quiet to unsettled geomagnetic conditions with possible active periods are expected to continue over the next days.

Estimation du nombre international de taches solaires (ISN) pour aujourd'hui : 076, sur la base de 08 stations.

Indices solaires pour 23 Sep 2014

Nombre de Wolf, observé par Catania	///
Flux solaire à 10 cm	138
AK Chambon La Forêt	021
AK Wingst	014
Ap estimé	014
Nombre international de taches solaires estimé	088 - Basé sur 23 stations

Résumé des événements marquants

Données fournies par le Solar Influences Data analysis Center© - SIDC - Traité par SpaceWeatherLive

Toutes les heures sont indiquées en UTC

<< Aller à l'aperçu quotidien