ARLA/CLUSTER: Abertura unusual entre a Europa e Austrália em 50 MHz no modo FT8 a 24 de Julho de 2019

[João Costa > CT1FBF]

Unusual opening from Europe to Australia on 50 MHz - 24th July 2019

Over the last few weeks, there have been some really good openings from
Europe to Japan on 50 MHz with many stations being worked by the FT8
digital mode.

During the morning of the 24th of July 2019 however, conditions were
exceptional as there was a highly unusual opening on 50 MHz from Europe to
Australia.

At least six VK3 stations in New South Wales in Australia were heard by or
had heard multiple European stations with distances in the region of 16,000
to 17,000 kms. This is all the more remarkable if one considers that half
the circumference of the Earth is 20,000 kms.

The best confirmed contact on the day seems to have been between EI3KD in
Ireland and VK3ZL near Melbourne in Australia with a distance of some
17,375 kms.

Contacts of this type on 50 MHz are usually only thought to be possible at
the peak of very good sunspot cycles like back in 1989. To have it happen
at the bottom of the current solar cycle is highly unusual.

The standard explanation for long distance openings like these on 50 MHz
during the Summer months is that it is because of multi-hop Sporadic-E.
However, the requirement for 8 to 9 hops to line up in a row does perhaps
challenge this assumption.

More info...
https://ei7gl.blogspot.com/2019/07/unusual-50-mhz-opening-from-australia.html
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