Propagation News 18 May 2014

| May 16, 2014

Several large and complex sunspot regions appeared during the period but none produced any sizeable solar flares. Solar activity was at low levels, with numerous C class solar flares taking place every day. The largest events were C8 class flares on the 10th and 14th. Solar flux levels increased from 152 units to 164 by the 11th before declining back to 152 by the end of the period. The average was 158 units. The 90 day solar flux average on the 15th was 150 units, that’s the same level as last week. X-ray flux levels showed little variation day to day and averaged B6.8 units. Geomagnetic activity was quiet every day, except for a very week disturbance from a recurring coronal hole on the 11th, when the Ap index was 12 units. The average was Ap 7 units. Solar wind data from the ACE spacecraft saw solar wind speeds vary between 320 and 420 kilometres per second. On most days particle densities were moderate, with 35 particles per cubic centimetre recorded on the 10th for example. Bz, both positive and negative values, remained in single figures every day.

Finally, the solar forecast for the coming week. This week the quiet side of the Sun is expected to be rotating to view. Solar activity is expected to be low with C class solar flares taking place with only a small chance of any stronger flares occurring. Solar flux levels should decline to around the 130s later in the week. Geomagnetic activity is expected to be quiet except for a small disturbance that will take place just after midweek. MUFs during daylight hours at equal latitudes are expected to be around 24MHz. Darkness hour lows should be about 14MHz. Paths this week to India should have a maximum usable frequency with a 50 per cent success rate of around 23MHz. The optimum working frequency with a 90 per cent success rate will be about 18MHz. The best times to try this path are 1000 and 1700 hours. Sporadic-E should take place on some days, with openings up to 70MHz possible.
And that’s all for this week from the propagation team.

Category: GB2RS Propagation News