Propagation – 17th March 2013

| March 17, 2013

And now the solar factual data for the period from Friday the 8th to Thursday the 14th of March, compiled by Neil Clarke, G0CAS on Friday the 15th of March

Up to eight sunspot regions were visible on the 11th but most were small and stable. However, a couple of groups produced occasional C class solar flares. Solar activity was very low for the first three days of the period but increased to low from the 11th. In total eight C class solar flares took place. The most impressive was a long duration C2 solar flare in connection with a filament eruption. Associated with this solar flare was a coronal mass ejection. Solar flux levels increased slightly from 115 units on the 8th to 123 by the 12th. The average was 120 units. The 90 day solar flux average on the 14th was 116 units, that’s one unit up on last week. X-ray flux levels varied little day to day and averaged B3.2 units. Geomagnetic activity was quiet every day and the average was Ap 4 units. Solar wind data from the ACE spacecraft saw solar wind speeds decline from 360 kilometres per second on the 8th to around 300 for the rest of the period, except for an increase late on the 14th to 400 kilometres per second. Particle densities were at moderate levels every day and varied between 12 and 45 particles per cubic centimetre. Bz varied between minus 5 and plus 6 nanoTeslas every day but increased to minus 7 and plus 9 nanoTeslas late on the 14th.

And finally the solar forecast for the coming week. This week the quiet side of the Sun is expected to be looking our way. Solar activity should be low with only C class solar flares taking place, however, on some days, activity could decline to very low levels. Solar flux levels should be around the 100 mark and may even dip slightly below 100 on several days. Geomagnetic activity is expected to be mostly quiet, but if a coronal mass ejection heads our way then activity would increase. MUFs during daylight hours at equal latitudes should be around 24MHz for the south and 21MHz for the north. Paths this week to Japan will 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 16MHz. The best time to try this path will be between 0800 and 1100 hours UTC.

And that’s all for this week from the propagation team.

Category: GB2RS Propagation News