Viewing archive of Wednesday, 18 October 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Oct 18 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 18 Oct 2017 until 20 Oct 2017
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
18 Oct 2017073007
19 Oct 2017074007
20 Oct 2017074007

Bulletin

Returning NOAA region 2682 (behind the East limb) produced a long duration B2.3 flare peaking around 10:30 UT on October 18. The chance for a C flare in the next 24 hours is estimated at 35%. NOAA 2682 erupted several times over the past 24 hours. Though data gaps in STEREO A imagery prevented to see the exact onset of some eruptions on the backside of the Sun, the events caused CMEs which were observed by LASCO C2 and C3. The two most significant CMEs (first seen in LASCO C2 images at 5:48 and 6:36 UT, respectively) were both bright and fast and extended from the northeast to the southeast, with a core towards the northeast. Since these are backside events, these CMEs will not be geoeffective. The greater than 10 MeV proton flux was at nominal levels. Solar wind speed measured by DSCOVR decreased from about 475 to about 390 km/s in the past 24 hours. The Interplanetary Magnetic Field (IMF) was predominantlty directed away from the Sun and its magnitude ranged between about 0 and 4 nT. Quiet geomagnetic conditions (K Dourbes between 1 and 2; NOAA Kp between 1 and 2) were registered in the past 24 hours. Quiet to unsettled geomagnetic levels are expected on October 18, 19 and 20.

Today's estimated international sunspot number (ISN): 000, based on 22 stations.

Solar indices for 17 Oct 2017

Wolf number Catania000
10cm solar flux070
AK Chambon La Forêt008
AK Wingst005
Estimated Ap004
Estimated international sunspot number000 - Based on 22 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-flare2025/04/01M2.5
Last geomagnetic storm2025/03/27Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
February 2025154.6 +17.6
April 2025147 -7.6
Last 30 days129.8 -18.9

This day in history*

Solar flares
12001X1.77
22017M8.35
31999M6.2
42001M3.57
52017M1.81
DstG
11979-168G4
21960-151G3
31992-105G2
42004-104G2
51994-103G3
*since 1994

Social networks