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Meteor echo of the day

 

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Seasons greetings.?

There's still plenty going on ! Do feel free to make your own live observations at:- . Here is a screenshot captured just now.

Note the same echo observed from different directions one of which uses Horizontal and Vertical polarisation.

All the best

Brian
 

Thanks for sharing.? What do you make of it???
BTW it is not possible for me to read data and time from screen image ... and it would be useful for comparisons.?
?
Mike
 

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I'm just catching up on emails. The time stamps below look to be 11:07:45 on 28/12/2024. If so, I have captured Graves NEO radar reflections from the same meteor at 11:07:48 via my horizontally polarised Yagi in West Oxfordshire - see attached Spectrum Lab screenshot.

Regards

Chris


On 28/12/2024 11:13, Brian wrote:

Seasons greetings.?

There's still plenty going on ! Do feel free to make your own live observations at:- . Here is a screenshot captured just now.

Note the same echo observed from different directions one of which uses Horizontal and Vertical polarisation.

All the best

Brian

event20241228_110815_4.jpg

 

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Hello Chris

Yes could be the same one. It's rather uncertain as to how Graves can illuminate an event that occurs in the region covered by? GB3MBA. Graves runs very high power and I see a strong direct signal here virtually all the time. It could be backscatter from the troposphere ??

Brian

On 30/12/2024 11:54, Chris Holt wrote:

I'm just catching up on emails. The time stamps below look to be 11:07:45 on 28/12/2024. If so, I have captured Graves NEO radar reflections from the same meteor at 11:07:48 via my horizontally polarised Yagi in West Oxfordshire - see attached Spectrum Lab screenshot.

Regards

Chris


On 28/12/2024 11:13, Brian wrote:

Seasons greetings.?

There's still plenty going on ! Do feel free to make your own live observations at:- . Here is a screenshot captured just now.

Note the same echo observed from different directions one of which uses Horizontal and Vertical polarisation.

All the best

Brian
 

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Hello Brian

There is good evidence that receivers of Graves meteor scatter in central southern England can detect scatter from meteors over NE France and the English Channel (e.g. Fleet, R., “Correlating video meteors with GRAVES radio detections from the UK”, in International Meteor Conference Mistelbach, Austria, 2015, p. 30). A meteor detected travelling across the GB3MBA region in a south easterly direction could pass over NE France soon thereafter and could account for my detection of it a few seconds later.

Chris

On 30/12/2024 15:36, Brian wrote:

Hello Chris

Yes could be the same one. It's rather uncertain as to how Graves can illuminate an event that occurs in the region covered by? GB3MBA. Graves runs very high power and I see a strong direct signal here virtually all the time. It could be backscatter from the troposphere ??

Brian

On 30/12/2024 11:54, Chris Holt wrote:

I'm just catching up on emails. The time stamps below look to be 11:07:45 on 28/12/2024. If so, I have captured Graves NEO radar reflections from the same meteor at 11:07:48 via my horizontally polarised Yagi in West Oxfordshire - see attached Spectrum Lab screenshot.

Regards

Chris


On 28/12/2024 11:13, Brian wrote:

Seasons greetings.?

There's still plenty going on ! Do feel free to make your own live observations at:- . Here is a screenshot captured just now.

Note the same echo observed from different directions one of which uses Horizontal and Vertical polarisation.

All the best

Brian
 

There is proof postive evidence that meteoroids have been detected over England, Wales and Scotland.
If you are interested in seeing the coverage and why,? there is a paper in WGN, Journal of the International Meteor Organization, vol. 51, no. 4, p. 72-92.? "Utilizing Video Meteor Trails to Understand Radio Meteor Detection"
This paper which is available to members on IMO website and via Research Gate.? I can send a copy if needed.
?
 

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Hello Mike

I am not? disputing that meteors over the UK can be detected by the GRAVES emissions. What I am saying is that the means by which the radiation from Graves reaches the region is not as obvious many believe.

The Graves antennas appear to be at ground level and beam up at an angle so the rear lobe heads into the ground. Any "side lobes" are so low down that they probably cant be the source of such a strong "direct" signal. So a possible source of the very strong signal that I see directly from GRAVES could be backscatter from the troposphere and it is likely that this is the source of illumination of meteors to the North.? This is not a reliable point source. In any case, why not use a system that provides defined coverage above the UK when one is available and even if you can't make your own receiver you can use the live streams at .

Here's a screen shot taken just now showing the very strong "direct" signal from GRAVES along with a meteor echo or two and one or more Starlink satellite echoes.


Brian

On 31/12/2024 15:12, Mike German via groups.io wrote:

There is proof postive evidence that meteoroids have been detected over England, Wales and Scotland.
If you are interested in seeing the coverage and why,? there is a paper in WGN, Journal of the International Meteor Organization, vol. 51, no. 4, p. 72-92.? "Utilizing Video Meteor Trails to Understand Radio Meteor Detection"
This paper which is available to members on IMO website and via Research Gate.? I can send a copy if needed.
?
 

The theory, and results are in the given paper.
also there is a description in there ISS passage to north of GRAVES and detections as conducted by the Collaborative Database exercise.
?
I am convinced that the specular reflection points expected in the forward scatter geometry arise from the rear beams of GRAVES. ?This is all evidenced in the paper which is open for comment. ?

The illumination over the UK is 24/7/365 with the diurnal profiles expect. ?It would be interesting to compare with the ?occurrences of tropo scatter

We should discuss this at some later date?
?
 

BTW I never see a 'direct' signal. ?

I do admit that the spectrogram images on the the lower frequencies can be far more exotic in nature ?... but remain a subject of conjecture as to the distribution of ionisation that cause them.?

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