Meteors and Aurora in the Midwest and MW/HF/VHF propagation

This year has been an outstanding one for the radio scientist, astronomer, amateur photographers and amateur radio operators. The sunspot number has been holding well above 100, yielding very busy HF conditions. Sporadic E-layer skip and August meteor trail skip from the Perseids led to some delightful intra-Midwest contacts not otherwise possible on 10 meters (28 MHz). Although I don’t have 6 meter (50 MHz) ham radio equipment, just turning on the TV this summer and fall and spinning the dial – even with rabbit ears – has seen a few days of several hundred kilometer TV reception.

Although I slept through the event, I was glad to hear of the Midwestern aurora in August coinciding with the Perseids in the early morning, plainly visible in the northern US.

European scientists from ESA ESTEC in Noordwik, Netherlands have been using narrowband receivers tuned to AM shortwave transmissions to monitor meteor trail echos on HF. One of the transmitter sites monitored in BBC in Zygi, Cyprus, which is about 3000 km from the receivers. Another is Wooferton in the UK, about 500 km from the receivers on 17.64 MHz. This is normally too short a distance for this frequency, so returns are expected from plasma enhancements from the meteor trails.

This is a far more sophisticated method than the AVC voltage monitoring I used to do in the AM MW band to monitor D-layer absorption vs. time and frequency.

Note we are not speaking about radio emission from the trails themselves, but strictly forward scatter of existing HF radio transmissions.