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Current propagation conditions (Some light at the End of the Tunnel?)

8 years to the day after the Mayan apocalypse? :slight_smile:

Hi Jeff,

Fair enough. I did not intend to be critical of you, just the paper’s claims.
Because some scientists publish a paper does not mean it can be relied upon. Often publishing is a way of testing the veracity of claims. In olden times reviewers were supposed to do that.

In the late1980’s a Nobel prize winner claimed to have discovered cold fusion. I attended one of his presentations. It seemed dodgy and my better qualified and older associates classified it as rubbish and a shame this guy had stained his reputation. They were right.

Water is really a gel (polywater) and one day all the oceans will turn to jelly was a serious claim by another hitherto respected scientist. It caused much merriment at the coffee break for a day or two.

We all need to be cautious about any claim to have discovered the truth when 100% accuracy is claimed or a single factor is cited as a cause. There is a name for research trying to prove things that are not true. It’s Pathological Science.

Keep your salt cellar handy and apply the grandmother’s rule. If it seems too good to be true it probably is.

73
Ron
VK3AFW

I just decided to toss it into the ring. I don’t know if it is accurate or not nor do I have the time to look up the raw data and check. I assume if a journal publishes it it’s not a total crack pot idea. Maybe that is my naivety. If the correlation lines up going back 90 solar cycles then if the claim was made 1000 years ago wouldn’t they have been right. We shall see when cycle 25 is officially here.

Jeff K6QCB

Am I missing the point here?

Sunspot cycles aren’t shaped like square waves but more like bell curves with gentle start and end slopes. So, obsessing about a ‘start’ date of the new cycle is pretty meaningless. What’s more, the curve is very ‘noisy’ so that the day-to-day variation will be bigger than the change in the averaged value for many months to come.

We might as well monitor Guru’s weekly transatlantic QSO count for the “start” than look for second and third order effects in the computer models.

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I think that this is a good time to point out that we are NOT waiting for the start of cycle 25, because in fact it has already started! There has been at least three active areas with the magnetic polarity reversed from that of Cycle 24, in fact there is one developing today, see www.spaceweather.com for a picture. It is normal for the cycles to overlap for a couple of years, so how do we decide the date of sunspot minimum? One method is to construct a Pogson curve, take the midpoint of horizontal lines drawn between the two cycles curves at various levels, the resulting dotted line will curve to point to the minimum date. More practically, though, we can take the date when spots from the new cycle outnumber the spots of the old cycle, and on that basis I don’t think we are quite there yet. Well, they say that patience is a virtue…

I agree, these are facts and they are always better than theories.
These are yesterday’s facts: they all were copied and chased with pretty good signals. The highlight was Keith @KR7RK in ARIZONA!


You can see the QSO distances on the right most column of my SAISIE SOTA log.


5 transatlantic QSOs in less than an hour ranging from nearly 7000Km to almost 9000 Km. Whether this is the begining of the new solar cycle is not that important, but the fact is that it’s a lot of fun after so long time of miserable conditions.
73,

Guru

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:+1:

Will someone turn the off the rain in Scotland please… we’ve had enough for now.

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Be patient, Andy - it will soon turn to snow!:grinning:

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Lol!

Same here. Forecast is for more or less continuous rain for the next 12 days. Call me a cissy but I don’t enjoy activating from inside a bothy bag.

Its ironic that I am looking out of the shack window at a clear blue sky - though last night the dog needed a snorkel for her walk!

Hi Brian,

Are you suggesting that the polarity reversals indicate the change from one cycle to the next?

This 2013 NASA article seems to suggest that the polarity reversals occur at the peak of the cycle …

I’m looking at this bit …
The sun’s magnetic field changes polarity approximately every 11 years. It happens at the peak of each solar cycle as the sun’s inner magnetic dynamo re-organizes itself. The coming reversal will mark the midpoint of Solar Cycle 24. Half of “solar max” will be behind us, with half yet to come.

Absolutely. Sunspot minimum is the time when the fields reverse, hence the presence at this time of sunspots ascribed to both cycles. This is in accordance with Hale’s Law:

"The cycle’s physical basis was elucidated by George Ellery Hale and collaborators, who in 1908 showed that sunspots were strongly magnetized (the first detection of magnetic fields beyond the Earth). In 1919 they showed that the magnetic polarity of sunspot pairs:

  • Is constant throughout a cycle;
  • Is opposite across the equator throughout a cycle;
  • Reverses itself from one cycle to the next."

from https://en.wikipedia.org/wiki/Solar_cycle

The NASA article appears to be incorrect.

Not incorrect… just talking about something else! (ie change of individual sunspot magnetic polarity at change between one cycle and the next vs change of polarity of the sun’s entire magnetic field at around cycle maximum)

Well last night I tried to find a spot on the 40m band to set myself up on for a Parks activation. It was wall to wall “CQ Oceania DX Competition”. I also got a S2S with Glen VK3YY who had a HF SSB Hand Held radio using just a telescopic whip, our summits were about 1,000KM apart.

I think this solar minimum stuff is about the minimum number of people calling and trying.
Compton

Well under the principal that if you ask 5 scientists for a definitive answer, you will get at least 7 different options … Here is another report about when Solar Cycle 24 will end and the slow bell-shaped climb up to better conditions with SC 25 will start - this is from Spaceweatherlive.com:

That being said, Compton I am happy that I was able to take advantage of the Oceania DX SSB contest and make 3 SSB contacts from the home QTH here into VK2, VK3 & VK6 on Saturday evening on 40m - so conditions can’t be totally dead and as you say - it can be more a matter of when people are on (my contacts were at about 7am local time in VK2&VK3) as much as actual propagation conditions.

73 Ed.

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And we haven’t even mentioned [so far in this thread, I think] the relationship between the aspect of solar physics we’ve been discussing and ionospheric propagation. Modelling the Sun-Earth system relevant to HF propagation must surely be difficult.

When I check online for band conditions, it would usually get the general situation more or less right (day vs night, summer vs winter) but individual bands might, in practice, be good/open and not poor/closed as predicted, or vice versa. So, now I skip the forecasts and just listen.

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:+1: same here.

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I skip the forecasts and just listen.
Same here.

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and I call as well…

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Compton, overall HF conditions seemed pretty good on Sunday. Besides our S2S, I worked ZL and several Australian states with great signals on 40m and 20m while using just the KX2 HF hand held (Diamond RHM8B). Thanks ants.

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