15,000km opening on 50 MHz between Australia & Europe - 4th June 2021

This will probably be my last post about the openings on 50 MHz between the north of Australia and Europe. Even though 15,000kms is a remarkable distance for 50 MHz near the bottom of the sunspot cycle and it may be a big deal for individual stations in Europe to work Australia, my interest is in the mode of propagation.

For the last few days, I've collected as much data as I could about these 6m Australia to Europe openings so that there is some sort of record online about them. Considering that they are now happening almost daily at present, I think the chances of them being solely due to multi-hop Spoardic-E is near zero. I don't believe it's possible to get 7-8 Sporadic-E hops at 50 MHz in the same direction day after day after day.

I'll keep a watch out for 50 MHz openings from Europe to the VK2/VK3 region which is the south-east of Australia as these are the exceptional openings at this stage.

Friday 4th June 2021: The map above shows the paths from VK4ABW in Darwin to Europe.

A list of the paths from European stations to Australia is shown below...

16,000km+ opening on 50 MHz from Australia to the Canary Islands - 2nd June 2021

Wednesday 2nd June 2021: Another day and yet another opening on 50 MHz between Europe and Australia. 

The longest path on the day however seems to have been between VK4ABW in Darwin on the north coast of Australia and EA8DBM on the island of Tenerife in the Canaries. The 50 MHz path which was on the FT8 mode works out to be around 16,220kms.

Just to put that in perspective, that's the same distance from Darwin to the Great Lakes in North America.

As the map shows above, the 50 MHz was also open to Europe and it managed to open up to G7RAU in the far south-west of England as well.

Txmtr Rcvr Band Mode Distance Time (UTC)
VK4ABW EA8DBM 6m FT8 16221 km 08:04:59
VK4ABW G7RAU 6m FT8 14234 km 07:09:27
VK4ABW OG2A 6m FT8 12147 km 07:56:45
VK4ABW LY2BAW 6m FT8 12144 km 08:47:42
VK4ABW LY2IJ 6m FT8 12094 km 07:32:29
VK4ABW YL2CP 6m FT8 12090 km 07:03:29
VK4ABW ES6RQ 6m FT8 12047 km 07:02:59
YL2GD VK4ABW 6m FT8 11984 km 06:59:44
UR5LAK VK4ABW 6m FT8 11332 km 08:59:44
VK4ABW UR0MC 6m FT8 11224 km 08:13:59
UT4MF VK4ABW 6m FT8 11166 km 08:38:14

* * * 

VK8MS in Darwin also heard EA8DBM but nothing from Europe.

Txmtr Band Mode Distance Time (UTC)
EA8DBM 6m FT8 16234 km 08:03:44

* * *

VK6KXW on the west coast of Australia managed to hear three stations in Europe.

Txmtr Rcvr Band Mode Distance Time (UTC)
IK0AGU VK6KXW 6m FT8 13357 km 05:26:29
YL2GD VK6KXW 6m FT8 12968 km 07:29:14
UT8IO VK6KXW 6m FT8 11840 km 05:57:44

* * *

There was also a path from VK4WTN on the east coast of Australia to two stations in eastern Europe.

Txmtr Rcvr Band Mode Distance Time (UTC)
VK4WTN UA4CC 6m FT8 13307 km 05:09:59

UR5LAK VK4WTN 6m FT8 13967 km 05:37:44

* * *

Mode of Propagation: The 50 MHz band has been open between Europe and Australia for four of the last fives days. Whatever the mode of propagation is, the simple 'it must be multi-hop Sporadic-E' is probably not the full explanation. 

It would be interesting to know if European stations working Japan, China and Australia are experiencing any skewed paths or is everything on the correct beam heading?

Another 50 MHz opening between Australia & Europe - Mon 31st May 2021

Following on from the weak opening on the 29th of May, there was another 50 MHz opening between Europe and Australia on Monday the 31st of May 2021.

The above map from the PSK Reporter website shows the almost 15,000km path that was open for VK4MA on the east coast of Australia.

SP4K 6m FT8 14993 km 07:43:30
LY2BAW 6m FT8 14683 km 07:46:59

***

There was a much bigger opening from VK4ABW on the north coast but he is also quite a bit closer with distances just over 12,000kms.

VK4ABW SM7CAD 6m FT8 12650 km 09:11:56
VK4ABW YL2CZ 6m FT8 12300 km 09:11:59
VK4ABW OG3G 6m FT8 12228 km 08:43:59
VK4ABW OH1MN 6m FT8 12199 km 08:44:29
VK4ABW OG2A 6m FT8 12147 km 08:43:59
VK4ABW LY2BAW 6m FT8 12144 km 08:46:57
VK4ABW OH7KM 6m FT8 12113 km 08:22:30
VK4ABW YL2II 6m FT8 12104 km 09:12:59
VK4ABW OH3SR 6m FT8 12091 km 08:22:26
VK4ABW YL2CP 6m FT8 12090 km 09:11:59
OH3JR VK4ABW 6m FT8 12081 km 08:36:44
VK4ABW ES5PC 6m FT8 11999 km 08:44:59

***

The longest paths came from the south-east of Australia. VK3OT was hearing the Ukraine.

UR5LAK VK3OT 6m FT8 14102 km 05:57:11
UR0MC VK3OT 6m FT8 13989 km 06:02:11

***

The longest path seems to have been between VK3ZL and SP4K in Poland at 15,459kms

SP4K VK3ZL 6m FT8 15459 km 05:20:44
UR0MC VK3ZL 6m FT8 14163 km 06:41:44

***

Propagation Mode: We're back to the same question again... How do 50 MHz signals from Europe reach Australia near the bottom of the sunspot cycle?

The easy 'go to' answer was that it was multi-hop Sporadic-E, case closed. 

The problem I'm starting to have with this is down to probabilities. 

Take SP4K in Poland. What are the chances of one hop Sp-E in the direction of Australia capable of supporting a 50 MHz signal? It's late May, it's the Summer Sp-E season so it's pretty high. 

Two hops?... What is the probability of getting two Sp-E regions spaced at just the right distance to allow a double hop at 50MHz? The probability is obviously lower.

Follow that same logic and apply it to 3 hops, 4 hops and so on. By the time we get to 15,459kms, we're probably looking at 8 hops. 

What is the probability of getting eight Sporadic-E clouds capable of supporting 50 MHz spaced at just the right distance from each other... all the way from Europe to Australia?

And if that probability wasn't low enough, what then is the probability of 8 hop Sp-E on 50 MHz from Europe to Australia on two out of three days?

I think the probability is now so low that there must be some other answer. Perhaps TEP (Trans-Equatorial Propagation) from Australia to China accounts for a large part of it? Some other propagation mode?

I'm not sure the simple 'It must be multi-hop Sporadic-E' adds up anymore.