Solar Cycle 25

Propagation questions, answers and general information
Jim (Bournemouth)
Posts: 304
Joined: 18 Sep 2014 05:59
Location: Bournemouth, Dorset IO90BR
Contact:

Solar Cycle 25

Post by Jim (Bournemouth) » 28 Aug 2017 20:42

With Cycle 24 now being well advanced on its downward path with solar minimum being expected in many quarters in 2019 or 2020, it is interesting that there are some optimistic signs that solar minimum may be comming sooner than we all think.

IN late December last year, some tiny sunspots at a high latitude with reversed polarity (compared with spots belonging to this cycle) were observed.

(Sunspots belonging to the next cycle generally have the opposite polarity compared with those belonging to the current cycle. Also, new cycle activity appears at high solar latitudes and the spots drift closer to the solar equator as the cycle proceeds.)

Then, earlier this month, another few spots were observed at high latitude also with reversed polarity. This together with some spotless but active regions known as "plage" at high latitudes this month. Then, today, I read this on http://www.solen.info/solar/ -
" The first cycle 25 spot observable at a 1K resolution was noted for several hours today. At noon the active region was located at N43W14, see linked image produced by my automatic spot counting software:

http://www.solen.info/solar/images/2017 ... ots_1k.png

The appearance of a cycle 25 region now could point to a solar cycle minimum in about a year.
This could be very good news.
It may mean that:

**The solar minimum could be sooner than expected.

** It could well be a relatively shallow minimum (the last one in 2008/9 was very deep)

** Cycle 25 could well be larger than Cycle 24 was, though current forecasts based on the extent of solar magnetic fields (which reverse once a cycle, at solar max) currently suggest that C25 will likely be equal or perhaps slightly larger than C24.

We shall see. But it could well be that predictions of a prolonged solar minimum ( "Dalton Minimum" ) could well be exaggerated.
Jim, Bournemouth, Dorset. IO90BR.

Elad FDM-S2, Perseus/FM+ and Funcube Dongle SDR Recievers 8-element OP-DES for Band 2, 12-ele ZL Special for 2m, plus wideband vertical
.

Image

User avatar
John Faulkner, Skegness
Posts: 4911
Joined: 19 Sep 2014 15:55
Location: Skegness, Lincolnshire. JO03dd
Contact:

Re: Solar Cycle 25

Post by John Faulkner, Skegness » 29 Aug 2017 10:51

Thanks for this interesting article Jim.

Medium Wave DXers won't be happy to read this. But this is quite the opposite of what was predicted for the forthcoming minimum. Being a medium wave DXer myself, I just hope they are wrong and the cycle 25 spots are premature.

Jim (Bournemouth)
Posts: 304
Joined: 18 Sep 2014 05:59
Location: Bournemouth, Dorset IO90BR
Contact:

Re: Solar Cycle 25

Post by Jim (Bournemouth) » 29 Aug 2017 12:58

Cheers John.

The post was written from the POV of an HF DX enthusiast, can understand MW types hoping for a long period of low solar activity!
Jim, Bournemouth, Dorset. IO90BR.

Elad FDM-S2, Perseus/FM+ and Funcube Dongle SDR Recievers 8-element OP-DES for Band 2, 12-ele ZL Special for 2m, plus wideband vertical
.

Image

Jim (Bournemouth)
Posts: 304
Joined: 18 Sep 2014 05:59
Location: Bournemouth, Dorset IO90BR
Contact:

Re: Solar Cycle 25

Post by Jim (Bournemouth) » 01 Feb 2018 14:07

An update. Bit of a rambling one.

If we ignore the peak in solar activity we had at the end of the summer, solar activity continues to drift slowly downward.
Solar flux levels have hovered around the 68-75 range (64-66 is regarded at rock bottom, usually during an average solar minimum, the odd day will see such values), and the running 3 month mean of daily solar flux valuers is 69.. so we are pretty much at solar minimum with regard to activity levels.
Of course, activity could stay low for 2-3 years as happened 10 years ago, but who knows!

We will quite likely see short-term quite small increases in sunspot activity attributable to Cycle 24 regions close to the solar equator over the next few months.

The key thing to look out for is the Cycle 25 sunspot regions.

The occasional region attributable to Cycle 25 have continued to pop up - perhaps half a dozen in the past few months. These are at a high solar latitude (35 degrees plus) and are of opposite polarity to those of the previous cycle.
When these new spot regions start to appear, in the past, official solar minimum has occurred up to about a year later. It is usual to see the old cycle regions continue to appear in tandem with a few new cycle regions, until the latter starts to outnumber the former and mean activity starts to rise. In the last solar minimum, Cycle 24 was so slow to get going that Cycle 23 spots had almost disappeared completely before more than the occasional Cycle 24 spot region started appearing, hence the long and deep minimum last time out. This time, the new cycle spots have shown up rather sooner.

As I previously mentioned, this to me is a strong sign that solar minimum may be sooner and shallower than the 2019/2020 that many are predicting.

The official date of the minimum won't be known until 8-12 months afterwards due to the way the data is smoothed, and centred 6 months either side of the date in question.
For example, if we see a big increase in activity from Cycle 25 regions in, say October, enough to affect 12-month smoothed means, the mimimum may well turn out to be in March this year. Not saying that will happen- it probably won't, but just to illustrate how the timing of solar minimum is determined.

I have a hunch that we *may* start to see Cycle 25 regions in larger numbers later this year.
Whether this will mean solar minimum is officially this year remains to be seen!
Jim, Bournemouth, Dorset. IO90BR.

Elad FDM-S2, Perseus/FM+ and Funcube Dongle SDR Recievers 8-element OP-DES for Band 2, 12-ele ZL Special for 2m, plus wideband vertical
.

Image

User avatar
John Faulkner, Skegness
Posts: 4911
Joined: 19 Sep 2014 15:55
Location: Skegness, Lincolnshire. JO03dd
Contact:

Re: Solar Cycle 25

Post by John Faulkner, Skegness » 01 Feb 2018 18:47

Thanks Jim.

Very interesting regarding the new cycle 25 sunspots. If we have 2-3 years of solar quiet, that will do me fine. I would hope that the next season sees a BIG improvement in lower frequency propagation. This winter has not shown any signs of a solar minimum in terms of reception, at least not from a MW DXer's perspective.

User avatar
Reggieman
Posts: 4
Joined: 15 Apr 2018 19:11

Re: Solar Cycle 25

Post by Reggieman » 18 Apr 2018 13:59

I was really lucky to catch this last F2 layer sunspot activity 2 years ago. Made the best contacts I ever did globally. I set up roadside out in the sticks got some super low interference and low noise locations and worked the world in the true sense of the word on a very cheap 10/11m radio. It was incredible fun whilst it lasted. May get out occasionally on a nice day/evenings for some Sporadic E this summer. Always a beautiful thing to speak to Europe/Scotland/NI/Ireland as the sun hits the horizon, good times... if you are that way inclined !

Very deep sunspot knowledge you have Jim. I only saw spots and thought must be good for DX but then realized not all sun spots are as good as others.That flux has something to do with it but never understood how.
All nice and cosy with the signals.

tvdxrools
Posts: 469
Joined: 01 Oct 2015 07:11

Re: Solar Cycle 25

Post by tvdxrools » 24 Apr 2018 14:58

Es very late in starting up here in Scotland on 11/10 meters and its been silent for a few months , David

Brookman Spark
Posts: 137
Joined: 19 Jan 2016 18:15

Re: Solar Cycle 25

Post by Brookman Spark » 24 Apr 2018 18:26

Not directly related to the cycle, or possibly not directly related to the cycle, I like this report on Spaceweather.com today:

The mysteries of last week's auroras:

There was no big explosion on the sun last week. So what caused the shock wave? No one knows. Despite the fact that there are multiple satellites keeping an eye on the sun 24/7, we missed something. The stealthy disturbance left the surface of the sun and traveled across the sun-Earth divide, unseen and undetected for several days, before it hit, sparking a moderately strong G2-class geomagnetic storm attended by strangely colored, widespread auroras. Surprises are still possible in space weather, after all.

satnipper
Posts: 896
Joined: 03 Oct 2014 12:58
Location: Western Europe

Re: Solar Cycle 25

Post by satnipper » 24 Apr 2018 20:18

The Es season starts 1 May - I would be surprised if last few months had not been quiet in Scotland lol

User avatar
John Faulkner, Skegness
Posts: 4911
Joined: 19 Sep 2014 15:55
Location: Skegness, Lincolnshire. JO03dd
Contact:

Re: Solar Cycle 25

Post by John Faulkner, Skegness » 24 Apr 2018 22:47

Are you saying that 10m/11m are usually active at this time of year David?

The aurora could have been caused by an emission from a distant sun. It happens.

pe1etr
Posts: 1270
Joined: 07 Oct 2014 00:40
Location: Kalar, Kurdistan (Iraq)

Re: Solar Cycle 25

Post by pe1etr » 25 Apr 2018 01:08

John Faulkner, Skegness wrote:
24 Apr 2018 22:47
Are you saying that 10m/11m are usually active at this time of year David?

The aurora could have been caused by an emission from a distant sun. It happens.
Betelgeuse going supernova?

User avatar
John Faulkner, Skegness
Posts: 4911
Joined: 19 Sep 2014 15:55
Location: Skegness, Lincolnshire. JO03dd
Contact:

Re: Solar Cycle 25

Post by John Faulkner, Skegness » 25 Apr 2018 01:58

;) If it increases the MUF then why not? Let's have two or three years of good MW conditions first.

Some years ago, a science programme on BBC R4 mentioned the possibilities of a distant sun causing geomagnetic disturbances on earth. One would hope that such a solar wind disturbance isn't too devastating.

tvdxrools
Posts: 469
Joined: 01 Oct 2015 07:11

Re: Solar Cycle 25

Post by tvdxrools » 25 Apr 2018 06:44

Are you saying that 10m/11m are usually active at this time of year David?

yes at this time of the year 11/10m should be showing some signs of Es but nothing so far , isnt it great how on some groups that people who have never dxed in a location for a long period of time seem to be a expert in the propagation that they get , ie a few 100 miles make a massive difference and paul farley the other day on 11m had and in his words 11m buzzing with italians etc yet not a peep up here , David

satnipper
Posts: 896
Joined: 03 Oct 2014 12:58
Location: Western Europe

Re: Solar Cycle 25

Post by satnipper » 25 Apr 2018 08:41

So the Sussex coast has had some pre-season Es and Scotland hasn't. Is this a surprise - it's what I would have expected.

tvdxrools
Posts: 469
Joined: 01 Oct 2015 07:11

Re: Solar Cycle 25

Post by tvdxrools » 25 Apr 2018 09:21

looking back through my logs i had plenty sporadic e end of march right through april thats what i would have had expected on 11/10m , my last decent qso on 11m was november to vk land and its been pretty silent till now , i know we arein the dreggs of a cycle but i expected Es to show up by now on the lower bands, atleast the long path to zl vk keeping me busy on 40m which has been great up here so far , David

satnipper
Posts: 896
Joined: 03 Oct 2014 12:58
Location: Western Europe

Re: Solar Cycle 25

Post by satnipper » 25 Apr 2018 10:01

You'll probably find the march/april QSOs were F layer - that is not possible now yet given the cycle position.

Es are not dependent on the sun spot cycle though Es/F layer combinations are certainly possible.

tvdxrools
Posts: 469
Joined: 01 Oct 2015 07:11

Re: Solar Cycle 25

Post by tvdxrools » 25 Apr 2018 10:07

i dont think short skip to belgium holland germany and shorter skip to cornwall etc was via f layer 18th april last year on 11m got some rec of it will put to utube when i get time as for mo off fishing , David

daveB
Posts: 1182
Joined: 07 Oct 2014 16:49

Re: Solar Cycle 25

Post by daveB » 25 Apr 2018 12:57

Some years ago, a science programme on BBC R4 mentioned the possibilities of a distant sun causing geomagnetic disturbances on earth.
I recommend "Twilight of Briarius" by Richard Cowper, published ages go, that explorers this very theme. It' sci-fi with romnce combination but one of my favourites - I've worn the paperback out.

So does the current state of the solar cycle mean less SpE or more SpE?

Out of interest these are the dates at my QTH when I consider the SpE season began.
2014 - 12 May, next opening 14 May - both openings were on the OIRT band (pre-SDR radio)
2015 - 28 Apr, next opening 30 Apr. This season was an early start
2016 - 04 May, next opening 07 May
2017 - 24 Apr, next opening 14 May

I started 24/7 monitoring to the East and South a few days ago. So far some enhanced tropo - 300-400 km - only.

David
SDRPlay, AirSpyMini, RTL dongles, SB920s, Yamaha TX930. 5 ele compact yagi on rotator at 18ft agl. FM5 facing east, FM5 facing south, FM3 facing NE, OIRT dipole, 3-ele Moxon vertical facing east.

satnipper
Posts: 896
Joined: 03 Oct 2014 12:58
Location: Western Europe

Re: Solar Cycle 25

Post by satnipper » 25 Apr 2018 15:01

"So does the current state of the solar cycle mean less SpE or more SpE?"

Nobody knows!!

2nd half of April skip to Benelux is probably Es. March it is probably the well known HF spring enhancement before the summer doldrums arrive once more.

User avatar
John Faulkner, Skegness
Posts: 4911
Joined: 19 Sep 2014 15:55
Location: Skegness, Lincolnshire. JO03dd
Contact:

Re: Solar Cycle 25

Post by John Faulkner, Skegness » 29 Apr 2018 09:21

I think you know the answer to that, Stuart. We'll just have to wait and see.

Interesting though that Jim Bacon spoke on how ionised meteor fragments are one possible (probable?) cause of E skip. This is worrying, however, since we have had very little of the pingy stuff lately that you might assume that there will be less fragments up there at the moment in view of this. So does this mean that we are in for a poor Es season this year?

Antipodean Es were reported to be good during their recent season, so could that be a sign that our season is likely to be better?

Last year's Es were the worst and the best on record for me. Days of nothing at all, then that incredible day of band-wide FM Es to Israel and Palestine.

Here's a fact: Predictions are not accurate.

Here's what to do: Make sure you don't leave your receiver! Better still, if you can afford to, get an SDR.

Post Reply

Return to “Propagation”