Propagation News – 9 February 2014

Two large sunspot regions produced numerous C class solar flares every day and solar activity increased to high on the 2nd and the 4th due to the fact that more than five M class solar flares took place during the same day. In fact seven occurred on the 2nd and in total 16 M-class flares took place during the period. Solar flux levels increased slightly more than forecast from 166 units on the 31st to 194 by the 5th. The average was 185 units. The 90 day solar flux average on the 6th was 155 units, that’s three units up on last week. Geomagnetic activity was quiet every day. The most disturbed day was the 6th with an Ap index of 7 units. The average was Ap 3 units. Solar wind data from the ACE spacecraft saw solar wind speeds increase from 300 kilometres per second on the 1st to 460 by the 5th. Particle densities were low every day except for a brief increase to 13 particles per cubic centimetre on the 4th. With the quiet magnetic field the magnetic component of the solar wind, the Bz, showed only minor variations of no more than minus 7 and plus 10 nanoTeslas during the period.

Finally, the solar forecast for the coming week. Presently, two large sunspot regions dominate the solar disc, however these will rotate out of view in the next day or two. Until then solar activity could be at moderate levels but then activity is expected to decline to low levels. Solar flux levels are expected to decline to around the 130’s or the 140’s. Geomagnetic activity could be unsettled today and tomorrow but then decline to quiet levels for the remainder of the period. However, there is a slight chance that a coronal mass ejection could head our way. MUFs during daylight hours at equal latitudes should be around 32MHz. Darkness hour lows should be about 9MHz. Paths this week to South Africa should see both the maximum usable frequency and the optimum working frequency above 30MHz. The best time to try this path will be between 0900 and 1700 hours UTC.

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

Category: GB2RS Propagation News