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Space Based Imaging

More data: SWAP, EUI

Ground Based Imaging

More: H-α, WL, Ca-IIK, Drawings

Ground Based Radio


Space Based Timelines

More data: LYRA, TSI

WDC Sunspot Index

More data: SILSO

Space Weather Services


Solar Map

Latest Alerts


No alerts since: 2024-04-19


  • Flare: M-class flares
  • Protons: Warning condition
    (increased activity)
  • Geomagnetic: Quiet
    (A<20 and K<4)
  • All quiet: False
  • Provisional SSN: 280

Solar Activity

URSIgram 2024-04-23

Solar flaring activity remained at moderate levels in the past 24 hours with multiple low M-class flares. There are 18 numbered and several unnumbered active regions on the visible solar disc with NOAA AR 3645 (beta-gamma) being the largest one, followed by NOAA AR 3647 (beta-gamma) and NOAA AR 3639 (beta-gamma). The strongest activity was M3.6 flare, start time 03:06 UTC, end time 03:37 UTC, peak time 03:19 UTC on April 23rd produced by NOAA AR 3654 (beta). This region was responsible for another M3.0-flare, peak time 08:21 UTC on April 23rd and continuous to be actively flaring. Isolated low M-class flaring was produced by regions NOAA 3645 and NOAA 3638. Other regions which contributed to the flaring activity are NOAA AR 3649 (beta), NOAA AR 3656 (beta) and NOAA AR 3646 (beta). The remaining active regions are relatively simple simple (magnetic type alpha or beta) and did not show significant flaring activity. The solar flaring activity is expected to remain at moderate levels over the next days with likely further M-class flaring and increased chances for isolated X-class flaring. No Earth-directed coronal mass ejections (CMEs) have been detected in the available coronagraph imagery over the past 24 hours. A small filament eruption was observed to the south of the central meridian starting around 1:40 UTC on April 23rd. A related chain of flaring activity was observed from regions NOAA 3654 (M3.4 flare, peak time 03:19 UTC on April 23rd) and region NOAA AR 3638 (C-class flaring, peaking at 01:22 UTC and 07:04 UTC on April 23rd) with an eastward and series of south-west CMEs detected by LASCO/C2 around 03:48 UTC and 07:36 UTC. Current analysis is ongoing to determine any potential Earth-directed components related to these eruptions. Over the past 24 hours the greater than 10 MeV GOES proton flux was at background levels and is expected to continue so over the next days, pending any fast eruptive solar activity. The greater than 2 MeV GOES 16 electron flux as measured by GOES 16 was below the 1000 pfu threshold and might reach the 1000 pfu threshold over the next 24h. The greater than 2 MeV electron flux as measured by GOES 18 briefly exceeded 1000 pfu threshold around 17 UTC and midnight UTC on April 22nd and is expected to cross the 1000 pfu threshold again in the late afternoon on April 23rd. The 24h electron fluence was at nominal level and is expected to remain so.

Solar Wind

URSIgram 2024-04-23

The geomagnetic conditions over the past 24 hours were globally quiet and locally in Belgium quiet to unsettled. Mostly quiet to unsettled geomagnetic conditions are expected throughout April 23rd and 24th. Quiet to active conditions with chances for isolated minor storms are anticipated for late April 25th-April 26th. Over the past 24 hours the solar wind parameters (ACE and DSCOVR) were indicative of background slow solar wind regime. The solar wind velocity was in the range of 335 km/s to 456 km/s. The interplanetary magnetic field was weak with a maximum value of 3.36 nT and a minimum Bz of -5.06 nT. The B field phi angle was predominantly in the negative sector (directed towards the Sun). The solar wind conditions are expected to remain at slow solar wind conditions in the next hours with possible mild elevations due to possible high speed stream arrival from a positive polarity coronal hole on April 25th - April 26th.



Soar like an eagle

Solar activity has risen dramatically during the last week, with sunspot numbers near their highest levels so far this solar cycle and an average of 2 to 3 M-class flares during almost every day.

Eye pleaser

A spectacular eruption took place on the Sun's farside on 11 April. The associated coronal mass ejection was not earth-directed.

Preparing for the eclipse

On 8 April 2024, a large part of the United States and Mexico will experience a total solar eclipse. Also at the STCE in Belgium, all eyes will be on the Sun. Three satellite instrument teams are preparing for unique, yet complementary, eclipse observations.


Ground Observations

The SIDC monitors the level of solar activity from the photosphere to the corona with ground based instruments located in Uccle and Humain.

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Space Instruments

To avoid the disturbing or blocking effect of the Earth atmosphere, EUV observations of the solar corona need to be made from space...

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Space Weather & Climate

We monitor and forecast solar variability to provide information services  to society and industry about the influence of space weather and climate.

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Data Processing & Distribution

Data processing is necessary to extract relevant information for research studies, whereas data distribution and visualization are part of ROB open data policy.

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Modelling of Solar phenomena allows scientists to test theories and to predict Space Weather phenomena and their impact on Earth.

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Supporting Research

The SIDC shares and expands its expertise through interaction with both upcoming and experienced researchers.

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