Propagation News – 29 August 2021
We had another week with a quiet Sun, but it wasn’t as settled as you might think. Yes, the solar flux index was in the low- to-mid-80s, but the Sun started to get very active. The first event on Sunday saw a prominence eruption off the west limb that flung a coronal mass ejection, or CME, into space. Another eruption near active region 2859 also launched a large amount of plasma into space, but luckily it was not headed towards Earth. So, by Thursday, we had two large sunspot groups visible, with perhaps region 2860 looking more and more active as it grows. Any potential CME activity occurring as a result of any solar flare this weekend will likely end up hitting the Earth.
DX was a little sparse, but there were some nuggets to be had. Josep, EA3BT, on holiday in Tanzania, was workable on 15m as 5I3B . And Pasi, OJ0W, on Market Reef, supplied CW QSOs for many stations on a mix of bands including 80 metres. Gary, G0FWX on the 10 metre UK Net Facebook group reported hearing Australia on 10m FT8 last week. Gary said: “I started working VKs in the middle of September on SSB last year, but this is a good sign”.
Next week, NOAA predicts the solar flux index will be in the mid-70s with mainly settled geomagnetic conditions. Friday the third is the exception, when the Kp index is set to rise to four.
Maximum usable frequencies are starting to rise a little thanks to seasonal changes, with 18MHz and even 21MHz often open during the daytime. These openings will likely firm up as we head towards mid-September and head into Autumn ionospheric conditions.
VHF and up
High pressure looks very likely to dominate the weather charts for the coming week and will continue the Tropo-themed weather pattern of the last few days. Unlike Sporadic-E, Tropo tends to be long lasting, but is usually better overnight and across sea paths like the North Sea or across Biscay to Spain and beyond to EA8. Don’t forget to try modes other than FM and FT8, such as SSB or CW – and do call CQ if the band is quiet.
Sporadic-E itself is looking less exciting as we head to the end of the current summer season. Fleeting events can still happen, and 10m will carry the most traffic with just the odd foray onto 6m on a good day.
Meteor scatter via random meteors is usually at its best in August, so keep looking around dawn to benefit from the pre-dawn enhancement. This is caused by the day side of earth rotating into the flux of meteors in the orbital plane.
There is just one small meteor shower this week, peaking on the 1st of September. The Aurigids have a low Zenithal Hourly Rate of just six.
The Moon reaches apogee on Monday so path losses will be at their highest for the month. On the positive side, peak declination occurs on Thursday so we have high peak elevations over 60 degrees meaning less ground noise at VHF and long Moon visibility windows.
Category: GB2RS Propagation News
