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Real-time lightning map, worldwide

blitzortung.org

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Re: Real-time lightning map, worldwide

#5

Post by wyred »

cipherzero wrote: post #3

How are they getting the data?

I would guess they have devices that detect light and sound. When the device detects a flash, it will start a timer and wait for the sound, which ends the timer.

Then based on the speed of sound, they can estimate the distance of the strike.

With many of these devices all over the place recording the data, using math, they can pinpoint the location of where the strike was.

Re: Real-time lightning map, worldwide

#8

Post by jjoonathan »

cipherzero wrote: post #4
cipherzero wrote: post #3

How are they getting the data?

It looks like they triangulate it somehow. But what is the input source?

http://www.blitzortung.org/Webpages/index.php?lang=en&page=5...

Electromagnetic (link is the "participants" tab on the top). You can tell because there's a smattering of telltale RF terms in the "comments" fields (coax, ferrites, E-field antenna, etc). I imagine that lightning strikes emit a fairly broad spectrum (localization in time -> delocalization in frequency) so the detectors might not all use the same band.

Re: Real-time lightning map, worldwide

#9

Post by 4mnt »

wyred wrote: post #5
cipherzero wrote: post #3

How are they getting the data?

I would guess they have devices that detect light and sound. When the device detects a flash, it will start a timer and wait for the sound, which ends the timer. Then based on the speed of sound, they can estimate the distance of the strike. With many of these devices all over the place recording the data, using math, they can pinpoint the location of where the strike was.

No sound, as it does not travel far enough and is easily disrupted by any other sounds in the area of the detector. I think it is just waiting for input of an electro-magnetical wave, then timestamps it and sends it to the server. The server can calculate the position with just the difference in arrival time to each station, and the position of those stations.
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