Welcome to the Solar Influences Data Analysis Center (SIDC), which is the solar physics research department of the Royal Observatory of Belgium. The SIDC includes the World Data Center for the sunspot index and the ISES Regional Warning Center Brussels for space weather forecasting.
Aug 18, 2015 DB: The Sunspot Number, the "longest ongoing scientific experiment" revisited


Solar activity remains very low, no C-class flares in past 24h. The
situation is not expected to change. A filament erupted close to the
western solar limb (located at ~S20W70) and produced a CME, first seen by
LASCO-C2 on 7 October 07:36 UT. It had an angular width around 100 degrees
and speeds of 400 km/s. The CME is directed towards the west. A possible
encounter with the Earth is not likely, but remains possible (on October

The Earth is still under the influence of the fast solar wind from an
equatorial coronal hole. The elevated speed of this solar wind stream
(peaked slightly above 800 km/s), together with elevated interplanetary
magnetic field (peaking around 25 nT with long southward excursions) have
created geomagnetic storm conditions since very early on October 7 until
now. Kp has reached 7 and the local K at Dourbes went up to 6. At present
the solar wind speed is still elevated (750 km/s) and although the
interplanetary magnetic field magnitude has decreased to 5 nT, more storm
periods can be expected in the coming 24 h. There is yet another coronal
hole at the Sun, in the northern hemisphere. Due to its irregular shape and
distribution in latitude it is difficult to estimate a single arrival time
for the fast solar wind. Its westernmost part may influence Earth in 24 to
48 h (although this region is at high latitude, 30 degrees north, so it may
not arrive to the Earth). The solar wind from the coronal hole’s
southernmost part (20 degrees north) will most likely come to the Earth in
72h. Therefore, more storms are expected in the coming days, possibly up to
major storm levels.

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

2015 Oct 07 2220 UTC
Severe geomagnetic storm in progress (Kp reaching 7) as a result of the [more]

2015 Oct 02 0048 UTC
A class M5.5 solar X-ray flare occurred on 2015/10/02 with peak time 00:13UT [more]

2015 Oct 01 0149 UTC
A halo or partial-halo CME was detected with the following characteristics: [more]

2015 Jun 02 0746 UTC
END OF ALL QUIET ALERT ...................... The SIDC [more]

Science Highlights

Oct 06, 2015: A two-stage CME

Sep 30, 2015: Rise and Shine!...

Sep 23, 2015: Another head-to-tail collision

Sep 16, 2015: PROBA2 observes an annular solar eclipse

Sep 09, 2015: Polar faculae near the Sun's south pole

click here for all science highlights


Aug 18, 2015 DB: The Sunspot Number, the "longest ongoing scientific experiment" revisited

Aug 11, 2015 PV: The Perseids - don't miss it

Jul 01, 2015 FC : Switching to the new Sunspot Number

Click here for all the press releases

Good to know

ASGARD - Balloons for science : Project call

ESWW12 - Early bird registration until October 1