Viewing archive of Tuesday, 17 April 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 Apr 17 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 17 Apr 2018 until 19 Apr 2018
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
17 Apr 2018069006
18 Apr 2018069006
19 Apr 2018068009

Bulletin

During last 24 hours three active regions emerged on the visible side of the Sun, but two of them already decayed. There are presently two numbered active regions observed, NOAA ARs 2704 and 2705, and both of them are spotless. The flaring activity is low and there were no C-class or even B-class flares reported. We expect such a low activity to persist in the coming hours. No Earth directed CMEs were observed in the coronagraph images, and the solar protons remained at the background level.

The Earth is still inside the slow solar wind with the speed of about 290 km/s and the interplanetary magnetic field magnitude is 3 nT. The increase of the solar wind speed, associated with equatorial coronal hole which reached central meridian on April 16 might be expected on April 19.The geomagnetic conditions are presently quiet and we expect them to stay so in the coming hours.

Today's estimated international sunspot number (ISN): 011, based on 20 stations.

Solar indices for 16 Apr 2018

Wolf number Catania012
10cm solar flux069
AK Chambon La Forêt006
AK Wingst002
Estimated Ap002
Estimated international sunspot number007 - Based on 32 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 2025152.5 -2.1
Last 30 days130.7 -17.9

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