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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

CACTus Halo 2023-05-28

A halo or partial-halo CME was detected with the following characteristics: t0 | dt0| pa | da | v | dv | minv| maxv| 2023-05-23T10:24:22.895 | 2.0 | 124 | 150 | 473 | 263 | 205 | 1116 t0: onset time, earliest indication of liftoff dt0: duration of liftoff (hours) pa: principal angle, counterclockwise from North (degrees) da: angular width of the CME (degrees), v: median velocity (km/s) dv: variation (1 sigma) of velocity over the width of the CME mindv: lowest velocity detected within the CME maxdv: highest velocity detected within the CME


  • Flare: M-class flares
  • Protons: Quiet
  • Geomagnetic: Active conditions
    (A>=20 or K=4)
  • All quiet: False
  • Provisional SSN: 145

Solar Activity

URSIgram 2023-06-01

There are ten visible active regions on the solar disk. The newly numbered NOAA AR 3223 (recently rotated into view over the east limb) is the one producing most of the flaring activity, including the largest flare of the past 24 hours: M4.3 peaking at 22:52 UTC on 31 May. NOAA AR 3315 and 3319 are also contributing to the flaring activity. More M-class flares can be expected and X-class flares are possible. No Earth-directed coronal mass ejections (CMEs) were detected in the past 24 hours. A positive polarity coronal hole in the southern hemisphere crossed the central meridian on 29 May. A related high speed solar wind stream may arrive to the Earth in the next 24 hours. Over the past 24 hours the greater than 10 MeV GOES proton flux was at nominal levels and is expected to remain so in the next 24 hours. The greater than 2 MeV electron flux was below the 1000 pfu threshold over the past 24 hours and is expected to remain so in the next 24 hours. The 24h electron fluence was at normal levels and is expected to remain at normal levels over the next 24 hours.

Solar Wind

URSIgram 2023-06-01

The geomagnetic conditions over the past 24 hours reached active levels (K_Belgium and Kp up to 4). More active to minor storm periods can be expected for the next 24 hours. The Earth is inside slow solar wind, but the solar wind speed has started to increase (currently at 450 km/s) with an interplanetary magnetic field around 7 nT. In the next 24 hours we will most likely see the arrival of the high speed stream emanating from a positive polarity coronal hole in the southern hemisphere (it is located at 20 degrees south in latitude, so we don’t expect a strong effect of the fast solar wind).



USET observes sunspots by eye

There was quite the excitement in USET team last week. Not one, but two sunspot regions were visible with the naked eye!

An M class flare observed with ROB ground based observatories

Ground based optical and radio solar instruments from ROB monitor together the recent period of increased solar activity

EUI can observe both elephants and mice among solar eruptions

The EUI telescope on Solar Orbiter was able to catch the miniature version of solar flares and mass ejections. Thanks to sharp and fast imaging of the EUI telescope, researchers could observe magnetic reconnection taking place repeatedly on very small scales.


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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