Viewing archive of Friday, 21 August 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Aug 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Aug 2015 until 23 Aug 2015
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
21 Aug 2015105009
22 Aug 2015106008
23 Aug 2015107010

Bulletin

Solar activity has increased over the past 24 hours, with Active Region (AR) 2403 (Macintosh:Dkc/Type:Beta-Gamma) showing significant flux emergence, and producing two M-class flares; a M1.2 flare peaking at 02:18 UT and a M1.4 flare peaking at 09:50 UT. The Sun also produced two Coronal Mass Ejections (CMEs); a slow CME first observed from beyond the south west limb at 02:48 UT on 20-Aug-2015, and a more energetic event from beyond the the north east limb at 10:12 UT on 20-Aug-2015. Both are believed to be back-sided and will not interact with the Earth. No evident Earth directed CMEs were produced in the past 24 hours. Solar activity is expected to remain active over the next 24 hours, with AR 2403 producing C-class flares with the possibility of M and X-class flares. The solar wind speed has been slowly decreasing over the past 24 hours, from 500 km/s to 450 km/s. The total interplanetary magnetic field (IMF) strength has been decreasing from 9 nT to 5 nT, and the Bz component has been fluctuating between -6 nT and +6 nT over the past 24 hours. Geomagnetic conditions varied between quiet and active over the past 24 hours, with the local K index (Dourbes) reaching 3 and the Kp index (NOAA) reaching 4 yesterday (2015-Aug-20), these conditions were possibly caused by a coronal hole (CH) located in the north-west region of the sun. The solar wind speed and IMF strength, as recorded by ACE, have both been decreasing and the geomagnetic field is expected to exhibit quiet levels over the next 24 hours.

Today's estimated international sunspot number (ISN): 079, based on 19 stations.

Solar indices for 20 Aug 2015

Wolf number Catania///
10cm solar flux103
AK Chambon La Forêt019
AK Wingst016
Estimated Ap017
Estimated international sunspot number064 - Based on 28 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
21015602180237S16E39M1.21F--/2403

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
12001X28.5
22001X2.01
32001X1.59
42014M9.35
52017M8.22
DstG
11960-272G3
21973-173G3
32001-101G1
41976-101G1
51994-96G3
*since 1994

Social networks