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| The solar factual data for the period from 17 November to the 23 November, compiled by Neil Clarke, G0CAS and Martin Harrison, G3USF | |
It was very quiet week all round. One small single spot rotated out of sight on the 17th leaving the solar disc spotless for the rest of the period. Solar activity was very low. Solar flux levels only varied by one unit throughout and averaged 69 units. The 90 day solar flux average on the 23rd was 68 units, that’s the same level as last week. X-ray flux levels remained below the minimum reporting level. Geomagnetic activity was also very quiet, in fact, the most disturbed day was the 23rd with an Ap index of only 3 units. Four days saw the Ap at one unit. The average was only Ap 2 units. Solar wind data at the ACE spacecraft saw solar wind speeds decline from 450 kilometres per second on the 17th to 260 by the 21st. Particle densities never increased to more than 3 particles per cubic centimetre. Bz only varied between minus and plus 4 nanoTeslas throughout. Like I said, a very quiet week. And finally the solar forecast. This week solar activity is expected to continue at very low levels. There is a small chance that activity could increase to low. Solar flux levels should be around the 70 mark, slightly lower than 70 if the solar disc remains spotless or slightly above if any small groups appear. Geomagnetic activity is expected to be at quiet levels till Thursday or Friday when a small coronal hole disturbance is expected to arrive. The disturbance should last no longer than a couple of days. MUFs during daylight hours at equal latitudes are expected to be around 20MHz for the south and 17MHz for the north. The darkness hour lows should be about 8MHz. Paths this week to the Middle East should have a maximum usable frequency with a 50 per cent success rate of around 21MHz. The optimum working frequency with a 90 per cent success rate will be about 18MHz. The best time to try this path will be between 1000 and 1500 hours UTC. |
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