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RAZoom Fri. April 5th 19:30 BST Solar Eclipse Effects on VLF Radio Propagation

 

We are pleased to welcome back Whit Reeve, a long time supporter of these seminars.
'October 14, 2023 Solar Eclipse ~ Effects on VLF Radio Propagation ~ Observed in Alaska USA' ~ Whitham D. Reeve.
Solar eclipses of one type or another occur a couple times each year on average. When the Sun’s radiation is blocked by the Moon, the characteristics of Earth’s ionosphere along the eclipse path change, and those changes affect radio propagation through that part of the ionosphere. Also, like the Sun’s visible light, its radio emissions detected by an observer in the eclipse path are reduced.?

The Zoom Room will be open from 19:30 BST, the link will be posted on Thursday 2nd. If you are not on the distribution list please contact me.
--
???? Paul Hearn? ???? ?paul@...? ???? ?RA Section Director? ???
 

The link has been mailed out.? Let me know if you have not received it.......
--
???? Paul Hearn? ???? ?paul@...? ???? ?RA Section Director? ???
 

Thanks for the interesting lecture!

My 2cents: there was a total eclipse in July 2009 and then I thought what is happening with Earth magnetic field during the event. So I made an screenshot from NOAA SWPC site then and attaching it now.?

These days dashboard is here:
https://www.swpc.noaa.gov/products/satellite-environment

Best regards,

?ilvis (LY2SS)
 

Hi??ilvis,

That is an interesting group of measurements. ?I understand there will reduction in electrons during an eclipse. ?So, are the electron currents at satellite altitudes affecting the magnetic field?
 

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I've attached a slide from the talk I gave some time back about SIDs and TIDs that shows my observations

of the 20th March 2015 eclipse.

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The eclipse was over 80% on the two paths in the slide and showed a very obvious effect.

I also show the 6 min delay between maximum eclipse and maximum effect at VLF that I mentioned yesterday.

?

Mark

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ion delay.jpg

 

Mike,

Honestly I don't know. We could see soon, in April 8th?
Judging from Kiruna magnetometer historical data there was magnetic field disturbance on that day:
 

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Hello,

??? ??? If anyone does record effects from the eclipse, then do please send them in for inclusion in our monthly summary, Radio Sky News.

Thanks,
John.

On 06/04/2024 17:13, Zilvinas, LY2SS wrote:

Mike,

Honestly I don't know. We could see soon, in April 8th?
Judging from Kiruna magnetometer historical data there was magnetic field disturbance on that day:
 

Mark - Nice plots! The eclipse effects are very pronounced and what I was expecting to see last October but didn't.

I'm setup with four virtual receivers (SDRduo) on the LF Comm frequencies and one (SDRdx) on the WWVB VLF frequency and started recording yesterday.

Based on past experience, each day is a new day when it comes to low frequency propagation. I usually see similar sunrise and sunset effects but not always, and daytime/nighttime signal levels vary all over the place. I'm not expecting anything different between now and Monday but one never knows.

Whit
--
Whitham D. Reeve
Anchorage, Alaska USA
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Cutler has been off air for the past few hours, but they've just switched it back on, just in time!

?

Mark
 

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Looking at all the eclipse watching parties everyone had a good time viewing the eclipse

and as I mentioned the powers that be decided that we vlf observers were not going to be disapointed!

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Just downloaded the data for Cutler (24.0kHz) and the picture shows the

plots from 6th , 7th and 8th April.

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Satisfyingly the peak at 19:50 on the 8th April trace matches my rough estimate of the time of totality at the

mid point between central England and Cutler.

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I'll send John more info when I've had time to do more analysis.

?

Cheers,

?

Mark

ecl240408.jpg

 

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Well done on catching that, just after the break!

John.

On 08/04/2024 21:31, Mark Edwards wrote:

Looking at all the eclipse watching parties everyone had a good time viewing the eclipse

and as I mentioned the powers that be decided that we vlf observers were not going to be disapointed!

?

Just downloaded the data for Cutler (24.0kHz) and the picture shows the

plots from 6th , 7th and 8th April.

?

Satisfyingly the peak at 19:50 on the 8th April trace matches my rough estimate of the time of totality at the

mid point between central England and Cutler.

?

I'll send John more info when I've had time to do more analysis.

?

Cheers,

?

Mark

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