Solar Influences Data Center (SIDC) / RWC Belgium
Royal Observatory of Belgium
E-mail: Pierre.Cugnon@oma.be
http://sidc.oma.be

SIDC WEEKLY BULLETIN
--------------------
WEEK 105 from 2002 Dec 30  

SOLAR ACTIVITY
--------------
Solar weather started very quiet this week. From December 30 until Jan.2, only a few flares, and 
with a low x-ray intensity level, occurred. These flares originated from the sunspot group 34 
(NOAA 0234).
Jan.3 promised a conversion in flaring activity. The back-ground x-ray increased to the C-class and
the number of flares increased.  This was caused by the appearance of two sunspot groups 02 and 03 
(NOAA 0242 and 0244 respectively) on the east limb. The promising start did not come through and 
flaring activity did not reach high peaks further this week.
The only event worth mentioning was a non-earth directed CME  observed around 13.00 UT on Jan.3 in 
association with an west limb located erupting solar filament. 

A small trans-equatorial coronal hole made the solar wind speed to increase from Jan.3. A peak of 
600 km/s was measured during the night between Jan. 3 and Jan. 4. From that moment, the speed 
decreased.

GEOMAGNETIC ACTIVITY
--------------------
The influence of the trans-equatorial coronal hole was visible in the  elevated values of K-indexes 
given by Wingst on Jan. 3 and Jan. 4. A peak in the K-index of 6 was measured. After the peak, the 
geoeffectiveness of the coronal hole diminished.





---------------------------------------------------------------------------
DAILY INDICES
DATE           RC   10CM   Ak   BKG    M   X
2002 Dec 30   044   114   012   B1.5   0   0
2002 Dec 31   071   115   007   B1.8   0   0
2003 Jan 01   043   115   008   B1.7   0   0
2003 Jan 02   043   118   008   B1.8   0   0
2003 Jan 03   113   138   028   B3.3   0   0
2003 Jan 04   121   143   020   B4.4   0   0
2003 Jan 05   106   148   010   B4.6   0   0
# RC  : Sunspot index from Catania Observatory (Italy)
# 10cm: 10.7 cm  radioflux (DRAO, Canada)
# Ak  : Ak Index Wingst (Germany)
# BKG : Background GOES X-ray level (NOAA, USA)
# M,X : Number of X-ray flares in M and X class, see below (NOAA, USA)
---------------------------------------------------------------------------
NOTICEABLE EVENTS
DAY BEGIN MAX  END  LOC   XRAY OP  10CM   TYPE               Cat  NOAA NOTE