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


Solar flaring activity is low. Catania group 45 (NOAA AR 2776 - alpha
classification) is very gradually decaying as is crossing the solar disk.
It was the source of B1.3-class flare on Oct 20 13:18UT. A B3.5 flare
originated from a small region on the north western limb. A new region has
appeared on the north eastern part of the visible disk. NOAA AR 2776 can be
the source of further more low A and possibly B-class flares in the coming

No Earth directed Coronal Mass Ejections (CMEs) were observed in the
available coronagraphic imagery.

The greater than 10 MeV proton flux was at background levels over the past
24 hours. It is expected to stay at background levels for the next 24
hours. The greater than 2 MeV electron flux was at nominal levels over the
past 24 hours. It is expected to remain at those levels over the next 24

Taking into account there was a lack of data from multiple instruments
between the time from Oct 21 00:50UT to Oct 21 07:51UT, the following
conditions of the solar wind can be reported. The speed of the solar wind
decreased slightly, varying between 345 and 430 km/s (DSCOVR). Temperature
and density decreased compared to the values 24 hours ago, but the latest
data indicate an increase. The polarity of the Interplanetary Magnetic
Field (IMF) varied, currently pointing towards the Sun (phi angle in the
negative sector). Bz fluctuated between -4 and +5 nT. The magnitude of the
magnetic field varied between 1 and 10 nT. The conditions could associated
with the high speed streams originating from the Coronal Holes (CH)
crossing of Central Meridian (CM) on Oct 16 and 17, while the current
extensions of the northern CH could explain the varying phi angle. Similar
conditions are expected in the coming hours.

The geomagnetic conditions were quiet to unsettled, with an active period
that started Oct 21 6:00UT (Kp=4). This could be associated with the HSS
from the CHs crossing CM Oct 16 and 17. The values registered for the past
24 hours were 0-3 for K Dourbes and 0-4 for NOAA Kp. Quiet to unsettled
conditions, with a possibility of active conditions, are expected for the
next 24 hours, reflecting the HSS from the CHs crossing CM the past days.

Latest SWAP image

SWAP latest image

Latest USET H-alpha image
USET latest Halpha image

Latest LYRA curve

Latest LYRA Curves

Latest Callisto Observations

Latest HUMAIN Callisto qkl

Daily estimated sunspot number

Most recent alerts

2020 Oct 21 1238 UTC
END OF ALL QUIET ALERT ...................... The SIDC [more]

2020 Oct 19 1824 UTC
The in situ observations show the arrival of the shock wave, Oct 19th at [more]

2018 May 04 1644 UTC
A halo or partial-halo CME was detected with the following characteristics: [more]

2017 Sep 10 1650 UTC
A class X8.9 solar X-ray flare occurred on 2017/09/10 with peak time 16:06UT [more]