Viewing archive of Wednesday, 23 August 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Aug 23 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 23 Aug 2017 until 25 Aug 2017
Solar flares

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

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
23 Aug 2017090025
24 Aug 2017091012
25 Aug 2017092005

Bulletin

Over the past 24 hours several C-class flares have been detected. The most energetic flares were two C1.9 class flares, produced by NOAA Active Region (AR) 2671. NOAA AR 2672 and Catania Sunspot group 44 produced only B-class flares. No Earth directed Coronal Mass Ejections (CMEs) have been detected. More C-class flares are expected during the next 24 hours, with a small chance of M-class flare.

Geomagnetic conditions have been disturbed due to the long period of negative Bz since early today, Kp reached 4 during 03-09 UT; the local K Dourbes also went up to 4 today. Solar wind speed is increasing again from 04 UT today and currently around 490 km/s. Simultaneously interplanetary magnetic field intensity is increasing and currently around 7.5 nT; Bz is constantly decreasing till actual value of -6 nT. Therefore, more disturbed conditions are expected in the next 24 hours with Kp up to 5.

Today's estimated international sunspot number (ISN): 066, based on 15 stations.

Solar indices for 22 Aug 2017

Wolf number Catania058
10cm solar flux090
AK Chambon La Forêt023
AK Wingst021
Estimated Ap023
Estimated international sunspot number059 - Based on 29 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

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

All times in UTC

<< Go to daily overview page

Latest news

Support SpaceWeatherLive.com!

A lot of people come to SpaceWeatherLive to follow the Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!

Donate SpaceWeatherLive Pro
Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2025/03/28X1.1
Last M-flare2025/04/01M2.4
Last geomagnetic storm2025/03/27Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
February 2025154.6 +17.6
Last 30 days128.1 -22.5

This day in history*

Solar flares
12001M7.89
22017M6.34
32001M5.75
42025M5.6
52024M3.9
DstG
11960-327G4
22001-228G2
31976-218G4
41973-211G4
51989-93G2
*since 1994

Social networks