Far East from Europe by E layer on 6m

Regularly, at this time of year, there are openings from Europe to the Far East on 6m.  This happens year after year about now. 

It appears to be linked to the formation of noctilucent clouds in the mesosphere. These are forming more frequently now because of global warming.  With weak signal modes like FT8, these are being spotted more often.

I have copied Far East stations on 6m several times now, although my 2.5W has never been enough!

See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/super-dx .

Far East on 6m

Even with my attenuator in, I was spotting a Japanese station on 6m FT8. At first, as it is very early in the season for this, which happens every year in late June/early July, I assumed this was a pirate. 

However, when I spotted a second one I began to believe this could be real. 

It is believed this propagation is linked to noctilucent clouds which form usually in June and July. With climate change these seem to be more common.

Super DX on VHF and above

About now, JA and other Far East stations are worked from Western Europe on 6m. This is linked to noctilucent clouds that form at this time of year. It is pretty regular. 

Indications suggest the path could work on higher frequencies too. I have not been checking 6m FT8 until yesterday.

See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/super-dx

Super VHF DX

In July for many years, stations in Europe have been able to work stations on 6m (VHF) in Japan. A look at the map will show this is a very long way. 

The most credible explanation is this is caused by ionisation in the mesosphere linked to the formation of noctilucent clouds that form at this time. From research, this path could work at even higher frequencies, possibly microwaves! What is needed is for keen people at each end to try. 

This is definitely a case when research by radio amateurs could advance radio science. There is much to be gained from this research. I think noctilucent clouds are becoming more common as a result of climate change, but don't quote me on this. Certainly Far East stations have been spotted here on just a vertical omni on 6m FT8 for several years in July.

Now is the time to arrange some skeds on 2m, 70cm or 23cm. Records could tumble.

See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/super-dx .

Super DX at VHF, UHF and microwaves?

On my website there is a page about super DX on VHF and UHF. Most, or every, summer there are 6m openings from Western Europe to the Far East. These are thought to be linked to noctilucent clouds in the mesosphere. It is possible these openings may occur at far higher frequencies. I am surprised nobody seems to be trying as there could be new records galore. 

I am not sure how FT8 works with noctilucent clouds, although I have certainly copied Japanese stations on 6m FT8 by this mechanism with a very poor setup. 

See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/super-dx . 

Super DX by E layer

Recently, there have been reports of DX contacts on 6m between New Zealand and South America. For as many late spring/early summers as I can remember there have been 6m VHF QSOs between western Europe and Japan.  All these QSOs appear to be via E layer, but I think these are too far for multi-hop Es.

My own theory is this is some sort of chordal hop E layer propagation. It always seems to be in late spring/early summer and is linked to noctilucent clouds which form in the mesosphere around this time (late June, early July in the northern hemisphere).

I get the impression that these modes may well work at far higher frequencies, possibly even microwaves.

See https://sites.google.com/view/g3xbm4/home/vhfuhfmicrowaves/super-dx . 

See also John's blog at https://ei7gl.blogspot.com/ .

VHF/UHF super-DX

Every year about now, 6m opens from Japan to western Europe. For a long time I have been of the view that this is E layer propagation, but not sporadic-E (Es). This is a very long way and it seems to be linked with noctilucent cloud formation. Southgate News reports on a Space weather piece about extremely cold temperatures in the mesosphere. Noctilucent clouds are forming at lower latitudes.

See http://www.southgatearc.org/news/2020/june/record-cold-in-the-mesosphere.htm#.XuD6RIjYrrcot

I have also got views on some of the other long paths worked on 6m such as the UK to the USA and the UK to South America. I am again convinced this is some sort of E layer propagation, but think it is very unlikely to be Es. OK, some openings could be Es, but the chance of this being multiple hop Es seems very unlikely. Maybe in 20 years' time we will know. In the meantime we have fun!

I also wonder if the Japanese path would also work on microwaves. Maybe one year some suitably equipped 23cm or even 3cm stations could have a try. Quite some firsts! Imagine if some EME equipped stations had a go.

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent

Japan on 6m?

In the first few weeks of June the 6m path from western Europe to Japan opens up regularly. This is a very long way. I recall a few years ago copying several JAs on 6m JT65. Personally I think this is indeed E layer propagation but not Es. I think it has something to do with E layer ionisation due to noctilucent clouds which form about now. Signals are usually weak and there in the early morning. This is a regular thing.

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent

Noctilucent Clouds

Southgate News passes on a Spaceweather report that noctilucent cloud formations are probably the best for years. Just about every June the path from Europe to Japan opens briefly on 6m VHF. This is thought linked to ionised mesospheric clouds. The openings are usually short lived and weak, but regular. The image is by creative commons user Novokaiin.

See http://southgatearc.org/clouds.htm#.XP4F7PZFy00

See also https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent

See also https://en.wikipedia.org/wiki/Noctilucent_cloud

Super VHF/UHF/SHF DX via noctilucent clouds?

In the next few months noctilucent clouds are often seen. There is a possibility that these are responsible for the very long 6m paths that regularly open from western Europe to Japan in the early summer. These openings are as regular as clockwork in the early summer, and then they just stop. It is a very long way on 6m and the conventional wisdom that this is multi-hop Es to me seems very unlikely. Last June, several Japanese stations were spotted on 6m JT65, even on my omnidirectional vertical.

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent

DX via noctilucent clouds?

These high altitude clouds appear most often around the summer solstice and support radar returns. It has yet to be tried, but it means very long distance UHF, SHF and microwave paths may be possible using these clouds. Who will try?

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent .

JAs on 6m?

It is the time of year when we tend to see the better equipped Western European 6m stations working Japan. This is a long way. The popular theory is this is multi-hop Es. Sorry, I just don't believe this.

Far more likely is reflections off noctilucent clouds that return strong VHF radar echoes. Noctilucent clouds are most common in high latitudes at this time of year and are 50-80km up.  The coincidence is just too great.

Sadly, there were no JAs active on 6m WSPR, so this weak signal mode is not going to help. Not sure if the Doppler on these weak signals would be too great anyway. It is a pity stations are not trying higher (even microwave) frequencies on this path. Fascinating. We still have a great deal to learn, but this is one mode that I am sure is under-used.

I know I mentioned this recently (blog entry June 3rd 2015), but when possibly new propagation modes are seen it is very important they are properly explored.  I have the feeling this is very important stuff. Imagine working Japan from Western Europe on 23cms or even 3cms. Wow!  Of course the same sort of path lengths would be possible in Canada and the USA. Get out there and explore!

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent .

6m Es - yes! 6m super DX?

6m WSPR has come to life with spots exchanged several times this afternoon with EA1KV (1304km).  DL4MFC (916km) spotted me on 6m WSPR at 1356z. Perhaps the 6m Es season is taking off at last? I notice there is thunder over central Europe. I wonder if this is helping? Sprites? I know one of the theories for Es involves thunder activity and upward movement into the E layer. Es is pretty complex.

No idea if the better equipped stations are working from Western Europe to Japan on 6m. This path seems to open every year around now, and some theories suggest reflections from mesospheric noctilucent clouds which are more common around this time of year. I suspect reflections would be possible right up to microwaves, but I doubt anyone is trying. See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent .

I am very suspicious of some of the multi-hop explanations for very long path Es. To me, there has to be a better explanation. Es yes. Multi-hop? Really? I have my doubts.  Some Europeans may indeed be multi-hop but some of the openings to South East Asia, Africa and South America?  I really doubt that many of these are multi-hop Es in the way most understand this. Some sort of chordal hops perhaps?

QSY to 10m or stick on 6m?

I am tempted to QSY down a band to 28MHz from 50MHz, but fear that 6m will then promptly open to the USA by multi-hop Es. It would just be my luck! Maybe I'll just stay on 6m and see what happens.

6m conditions have been very good today. Early June is getting close to the best times for Es DX on 6m.

I seem to recall regular openings to Japan from western Europe on 6m about this time. There was some speculation about the mode as it is FAR too far for Es and there were thoughts that noctilucent clouds may be significant. Openings were usually morning weak affairs and a decent station was needed. Don't think WSPR has been tried but Doppler might be a killer as the path crosses the auroral oval. Whatever the mode, this is fascinating stuff. 6m yet again throwing up propagation puzzles. I also wonder just how many so called "multi-hop" Es openings are actually some other mode?   Some of the very long paths towards the Far East, Africa and the Americas make you wonder.

This sort of DX is still good in years of low solar activity. Just because the sunspot count can be VERY low does not mean low-VHF has no real DX. In many ways the quiet solar years are more interesting.

UPDATE 1900z:  No Es DX now since 1446z. Still hopeful the band might open across the Atlantic this evening.

A VHF/UHF DX mode waiting to be discovered?

There is some indication that the long Europe to Japan path on 50MHz in the summer months is due to Polar Mesospheric Summer Echoes, or PMSE for short. Echoes of 224MHz radar in Norway suggest strong reflections, so I wonder why more radio amateurs are not trying for 2m DX using these mesospheric clouds?

See http://www.eiscat.se/raw/pmse.html. It is very likely these clouds and noctilucent clouds are the same phenomenon.

Fabulous noctilucent cloud image

Check out this image of a noctilucent cloud formation. See http://www.spaceweather.com/swpod2010/10jul10/CROISIER-Alexandre1.jpg

Noctilucent Cloud storm

Recent nights have been good for these high altitude night-time visible mesospheric clouds which return strong microwave echoes, so should be good for 10GHz super-DX. See www.spaceweather.com

NOCTILUCENT STORM: Last night, sky watchers in Europe witnessed the finest display of noctilucent clouds (NLCs) so far this year. Electric-blue tendrils spread as far south as France:"I could see the NLCs from my window," says photographer Alexandre Croisier of Brittany, France. "So I rushed down to the beach to take this picture--a 6 second exposure with my Canon 350D.  

In England, the same display stretched from horizon to horizon. "There was quite a lot of detail visible, including swirls and tiger stripes," reports Mark Jones of Leamington Spa, UK. Even city lights did not overwhelm the NLCs. "I had no trouble seeing them from southwest London," says onlooker Maurice Gavin.

July is often the best month of the year to see these mysterious clouds. High-latitude sky watchers should be alert for electric blue in the nights ahead.

Noctilucent Clouds and microwave DX?

Noctilucent, very high altitude, night time visible, clouds are becoming more common and at lower latitudes. This may be a result of climate change. One phenomenon associated with these is strong microwave radar echoes, raising the possibilty of very long distance DX by reflection from these on bands like 10GHz. This is an area ripe for experimentation but I am unaware of ANY groups anywhere investigating this exciting new propagation mode.

There is a  link between noctilucent clouds and the solar cycle with NLC activity peaking just after solar minimum, possibly because low solar activity allows the upper atmosphere to cool, promoting the growth of ice crystals that make up the clouds.  See http://spaceweather.com/

Noctilucent cloud DX - microwave mega DX mode?

There was a MOST interesting note on the ARRL propagation report tonight:

"Noctilucent Clouds Return - As reported at spaceweather.com on June 1, the first noctilucent clouds (NLC) of the 2009 season were sighted over Russia on May 27. NLCs typically appear about 20 days prior to the summer solstice, increase quickly to a high summer level, and then disappear about 50 days after the summer solstice. These clouds are mostly a high latitude phenomenon, and are believed to be composed of ice crystals. VHF radars see very strong echoes from these clouds, and since they are at mesospheric heights (80 to 90 km), they are also known as polar mesosphere summer echoes (PMSE). These clouds are hypothesized by JE1BMJ and others to be responsible for 6m propagation across high latitudes (for example,
from the East Coast of North America to Japan) during the northern hemisphere summer. This mode of propagation has been dubbed Summer Solstice Short-path Propagation (SSSP). Check out page 34 of the February 2009 issue of WorldRadio Online (available free at
www.cq-amateur-radio.com/wr_back_issues.html) for a general discussion of PMSE and SSSP and for references in the technical literature. To reiterate, SSSP is still just a theory,
but the occurrences of QSOs appear to match the occurrence pattern of PMSE."

Now, there is also evidence (from radar returns) that microwave DX might be possible using the same noctilucent clouds, possibly allowing superb DX possibilities on 10GHz possibly even with low power.

This is a whole area of future ham research just waiting to be exploited. It may be one upside of global warming as these high altitude clouds are now more common than hitherto.

For more on these mesospheric clouds see http://www.chiandh.me.uk/p/Noctilucent_cloud#Results