Viewing archive of Sunday, 17 December 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Dec 17 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 17 Dec 2017 until 19 Dec 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
17 Dec 2017071036
18 Dec 2017071029
19 Dec 2017071015

Bulletin

The Sun produced no C flares in the past 24 hours. The chance for a C flare in the next 24 hours is estimated at 5%. No Earth-directed Coronal Mass Ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux was at nominal levels. DSCOVR observed a disturbance in the solar wind around 21h UT on December 16. Since then, solar wind speed has increased to current values around 600 km/s. The Interplanetary Magnetic Field (IMF) was mainly directed away from the Sun and its magnitude has increased from about 4 nT before 21h UT to values up to about 16 nT. Bz was variable and was consistently below -5 nT from about 3:30 until 6:00 UT. The observed enhancement in solar wind conditions is probably due to the arrival of an expected high speed stream of a recurrent positive equatorial coronal hole. Quiet to active geomagnetic conditions (K Dourbes between 0 and 4; NOAA Kp between 1 and 5) were registered in the past 24 hours. Active to moderate storm conditions (K Dourbes = 4 to 6) are possible on December 17 and 18. Active geomagnetic conditions (K Dourbes = 4) are possible on December 19, with a chance for minor geomagnetic storm intervals (K Dourbes = 5).

Today's estimated international sunspot number (ISN): 000, based on 16 stations.

Solar indices for 16 Dec 2017

Wolf number Catania///
10cm solar flux071
AK Chambon La Forêt012
AK Wingst003
Estimated Ap003
Estimated international sunspot number000 - Based on 25 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-flare2025/04/01M5.6
Last geomagnetic storm2025/03/27Kp5 (G1)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
February 2025154.6 +17.6
Last 30 days128.5 -22.7

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