Viewing archive of Tuesday, 23 May 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 May 23 1230 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
23 May 2017	076	008
24 May 2017	077	010
25 May 2017	078	011

Bulletin

Over the past 24 hours solar activity has been low. There has been one B1.5 flare peaking at 22:05 UT on 22-May-2017, coming from NOAA Active Region (AR) 2660 (McIntosh class:Hsx; Mag.Type:Alpha). NOAA AR 2658 (McIntosh class: Hsx; Mag.Type:Alpha) and AR 2659 (McIntosh class:Cro; Mag.Type:Beta) have shown some evidence of flux emergence and cancellation in HMI magnetogram observations, this may increase flaring activity. No Earth directed Coronal Mass Ejections (CMEs) have been detected. Integral proton flux for protons with energies above 10 MeV remained at background level. Solar activity is expected to remain low over the next 24 hours with a probability of C-class flares.

Solar wind speed increased from about 520 km/s to values around 620 km/s (20:00 UT on 22-May-2017) but then gradually decreased again till 520 km/s. The total interplanetary magnetic field (IMF) strength, as recorded by the DSCOVR satellite, was around 5 nT. Bz fluctuated between -5 and +5 nT the first half of the observational period later decreasing event further. Geomagnetic conditions were from unsettled to quiet in the past 24 hours (K Dourbes between 1 and 3; NOAA Kp between 1 and 3). Solar wind speed and interplanetary magnetic field variations are expected to decrease further today. In response geomagnetic conditions are likely to experience mostly quiet to unsettled conditions today and tomorrow.

Today's estimated international sunspot number (ISN): 056, based on 24 stations.

Solar indices for 22 May 2017

Wolf number Catania	070
10cm solar flux	074
AK Chambon La Forêt	017
AK Wingst	014
Estimated Ap	013
Estimated international sunspot number	050 - Based on 31 stations

Noticeable events summary

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

All times in UTC

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