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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: Quiet
    (A<20 and K<4)
  • All quiet: False
  • Provisional SSN: 157

Solar Activity

URSIgram 2023-05-29

There are seven visible active regions on the solar disk. Only minor C-class flaring has been observed in the last 24 hours. These flares originated in NOAA ar 3315, 3314 and a region rotating into view from the east limb. This region produced the largest flare of the past 24 hours, a C2.3 flare peaking at 07:39 UT. NOAA AR 3315, with beta-gamma-delta magnetic field configuration, has potential to produce larger flares. There will be C-class flares in the next 24 hours, and M-class flares are possible. No Earth-directed coronal mass ejections (CMEs)were detected in the available coronagraph imagery. A positive polarity coronal hole in the southern hemisphere crossed the central meridian today. A related high speed solar wind stream may arrive to the Earth on 1 June. Over the past 24 hours the greater than 10 MeV GOES proton flux was at nominal levels and is expected to remain so over the next days. 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 2023-05-29

The geomagnetic conditions over the past 24 hours were quiet to unsettled (K_Belgium and Kp up to 3). Mostly quiet geomagnetic conditions are expected, with chances of active levels if we see the glancing blow from the 25-26 May CMEs or the high speed stream from the negative polarity coronal hole in the northern hemisphere. The Earth is inside slow solar wind, with an interplanetary magnetic field around 5 nT and solar wind speed of about 370 km/s. Similar conditions are expected for the next 24 hours, with a (low) probability of seeing a glancing blow from the CMEs of 25-26 May. Furthermore, the solar wind from a small coronal hole with negative polarity in the northern hemisphere may arrive to the Earth in th next 24 hours, but since the coronal hole is located at high latitude, the corresponding high speed stream may miss the Earth.



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.

First eclipse of the year observed by PROBA2

In the early hours of April 20 a solar eclipse took place. Regions on Earth that saw, at least, a partial eclipse include parts of South/East Asia, Australia, and Antarctica. This meant that only a very small fraction of the world's population was able to witness this event. Even if it was a difficult eclipse to observe from the ground, PROBA2 had a front-row seat!


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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