The SIDC is part of the Royal Observatory of Belgium and a partner in the Solar Terrestrial Center of Excellence (STCE).


The solar activity has been quiet over the past 24 hours, with the X-ray
flux below C-level. A small bipolar sunspot groups (Catania sunspot group
25) is visible on the disc, no significant faring activity has been
observed within this sunspot. The solar activity is expected to remain low
levels over the next 24 hours. 

Yesterday a large coronal dimming was observed from 08:03 UTC to 09:33 UTC
on July 28 in the north-west quadrant. The associated coronal mass ejection
was then observed on the SOHO/LASCO-C2 coronagraphe images on July 28 at
10:36. The projected speed was estimated around 400 km/s and the true speed
around 520 km/s. The arrival time on Earth of the coronal mass ejection
glancing blow is estimated on July 31 around 22:00 UTC (+/-12h). Only minor
to no effect is expected on the solar wind conditions and geomagnetic
activity from this CME.

The greater than 10 MeV proton flux was at nominal levels over the past 24
hours and is expected to remain so for the next 24 hours. The greater than
2 MeV electron flux was below the 1000 pfu threshold in the past 24 hours.
The greater than 2 MeV electron flux may slightly increase during the next
24 hours due to the high-speed streams. The 24h electron fluence was at
normal levels in the last 24 hours and may also slightly increase for the
next 24 hours.

The solar wind parameters (as observed by ACE and DSCOVR) are enhanced due
to the high-speed streams associated with the positive polarity northern
polar coronal hole, that crossed the central meridian on July 24. The solar
wind speed fluctuated around 510-515 km/s. The interplanetary magnetic
field magnitude remained enhanced at the beginning of the period (up to 14
nT) then decreased to values below 7 nT. The Bz component mainly positive
(with values between -6 nT and 14 nT) then returned to nominal values. The
enhanced solar wind conditions are expected to persist for the next few

The geomagnetic conditions were unsettled in responses to the high-speed
streams (NOAA-Kp and K-Dourbes = 3). The conditions are expected to be
mainly quiet with possible short periods of unsettled conditions. 

Latest SWAP image

SWAP latest image

Latest USET H-alpha image
USET latest Halpha image

Latest LYRA curve

Latest LYRA Curves

Latest Callisto Observations

Daily estimated sunspot number

Most recent alerts

2021 Jul 25 1238 UTC
START OF ALL QUIET ALERT ........................ The SIDC - RWC Belgium [more]

2021 Jul 17 1040 UTC
A halo or partial-halo CME was detected with the following characteristics: [more]

2021 Jul 17 1138 UTC
A halo CME was observed on LASCO C2 starting at 05:36 UT on 17 July. This [more]

2021 Jul 03 1820 UTC
A class X1.5 solar X-ray flare occurred on 2021/07/03 with peak time 14:29UT [more]