Affichage des archives de mercredi, 21 janvier 2026

Bulletin quotidien sur l'activité solaire et géomagnétique du SIDC

Publié: 2026 Jan 21 1231 UTC

Prévisions SIDC

Éruptions solaires

M-class flares expected (probability >=50%)

Géomagnétisme

Moderate (ISES: Major) magstorm expected (A>=50 or K=6)

Moniteur de Flux de Proton

Proton event in progress (>10 MeV)

	Flux de 10 cm	Ap
21 Jan 2026	182	039
22 Jan 2026	182	019
23 Jan 2026	182	007

Régions solaires actives et éruptions solaires

Solar flaring activity was moderate over the past 24 hours, with two M-class flares observed. A total of 12 numbered sunspot groups were identified on the disk. The largest event was an M3.4 flare (SIDC Flare 6701) peaking on January 21 at 07:12 UTC, produced by SIDC Sunspot Group 769 (NOAA Active Region 4349). An additional M1.1 flare (SIDC Flare 6699) peaking on January 21 at 01:35 UTC was produced by SIDC Sunspot Group 766 (NOAA Active Region 4345). SIDC Sunspot Group 762 (NOAA Active Region 4342), currently located at N14W04, maintained a Beta-Gamma magnetic configuration over the past 24 hours. SIDC Sunspot Group 766 (NOAA Active Region 4345), currently located at S17W02, also maintained a Beta- Gamma magnetic configuration over the past 24 hours. Solar flaring activity is expected to remain moderate over the next 24 hours, with C-class flares expected and M-class flares likely.

Éjection de masse coronale

No Earth-directed coronal mass ejection (CME) were observed in SOHO/LASCO images over the past 24 hours.

Trous coronaux

SIDC Coronal Hole 146 (trans-equatorial coronal hole with a positive polarity) first reached the central meridian on January 16 and is now partially positioned on the western side of the Sun.

Vent solaire

Over the past 24 hours, Earth remained under the influence of the interplanetary CME (ICME) associated with the full-halo CME observed in SOHO/LASCO C2 on 2026 Jan 18 at 18:12 UTC (linked to the X1.9 flare, SIDC Flare 6678, peaking at 18:09 UTC from SIDC Sunspot Group 740, NOAA AR 4341, and accompanied by Type II radio emission). Solar wind speed stayed elevated but showed a slow decline, ranging from about 1014 km/s down to about 650-700 km/s. The interplanetary magnetic field (IMF) also weakened compared to the initial impact, with total IMF, Bt, varying up to about 22 nT, while North-South component of the IMF, Bz, remained predominantly southward, ranging from about -18 nT to +3 nT. Continued disturbed solar wind conditions are expected while the ICME tail and trailing structures pass, with a gradual return toward slower background solar wind once the ICME influence fades.

Géomagnétisme

Sustained high solar wind speed combined with long intervals of southward interplanetary magnetic field (IMF), Bz, maintained storm conditions for much of the past 24 hours. Globally, NOAA Kp remained mostly at major storm levels (around Kp 7), with severe storm intervals reaching Kp 8- during the 09:00 to 12:00 UTC and 21:00 to 24:00 UTC periods on January 20. Locally over Belgium, K_BEL stayed mainly in the active to moderate storm range (K_BEL 5 to 6), reaching 6 during 10:00 to 12:00 UTC and again from about 19:00 UTC until around 03:00 UTC, then gradually easing toward active levels later in the period. Further moderate storm intervals remain possible if Bz turns more strongly southward again, but a slow recovery is expected as the ICME weakens.

Niveaux de flux de protons

The solar energetic particle event associated with the X1.9 flare (SIDC Flare 6678, peaking on 2026 Jan 18 at 18:09 UTC) is still ongoing. The greater than 10 MeV GOES proton flux has been above the 10 pfu threshold since 2026 Jan 18 at 22:50 UTC and remains above it. The greater than 10 MeV flux is currently decaying toward the threshold and is expected to decrease further, likely dropping below the threshold within the next 24 hours. A new solar energetic particle event cannot be excluded given the number of sunspot groups currently on the visible disk, in particular the most magnetically complex regions.

Flux d'électrons sur l'orbite géostationnaire

The greater than 2 MeV GOES electron flux stayed close to the 1000 pfu alert threshold over the past 24 hours and showed a renewed increase toward the end of the interval, intermittently exceeding the threshold. With solar wind speeds still elevated and geomagnetic conditions gradually moving into a recovery phase, the greater than 2 MeV electron flux may remain near or above the threshold during the next 24 hours. The 24-hour electron fluence remained at moderate levels and is expected to stay around these levels, with a possible increase if elevated electron flux persists.

Estimation du nombre international de taches solaires (ISN) pour aujourd'hui : 164, sur la base de 07 stations.

Indices solaires pour 20 Jan 2026

Nombre de Wolf, observé par Catania	///
Flux solaire à 10 cm	178
AK Chambon La Forêt	146
AK Wingst	120
Ap estimé	132
Nombre international de taches solaires estimé	172 - Basé sur 18 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