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comment by thenewgreen
thenewgreen  ·  3810 days ago  ·  link  ·    ·  parent  ·  post: A real time map of lighting strikes.

This is probably a dumb question, but it says that this is community run, does this mean that what I am seeing are reports from people physically documenting lightning strikes or is there some sort of machine or mechanism that captures the data somehow?





ButterflyEffect  ·  3810 days ago  ·  link  ·  

The Cover Your Area page talks about the technical side of things. People can purchase or otherwise construct their own receiver systems and feed the data to a server.

Reading through the PDF of the project description, it looks like there's a receiver that measures radio frequencies, which when used in conjunction with electromagnetic fields generated by a lightning strike allows the position to be determined.

This is some interesting stuff.

user-inactivated  ·  3810 days ago  ·  link  ·  

How does it detect the strikes that are over miles of ocean if it's all based on a circuit board connected to the internet like that?

ButterflyEffect  ·  3810 days ago  ·  link  ·  

I'm going to copy/paste a chunk from section 3.3 that explains some of this better than I could. If you have any questions beyond that I might be able to answer them.

    The TOA lightning location technique is based on the computations of hyperbolic curves. The emitted radio signal of a lightning discharge is traveling through the air with the speed of light. This is approximately 300000 kilometers per second, or equivalently, 300 meters per microsecond. Each received signal gets a time stamp. Let t_A (s) be the time stamp for signal s from station A. Time stamp t_A (s) is the Coordinated Universal Time (abbreviated UTC) in microseconds with an accuracy of +/- 1 microsecond. The difference of two time stamps for the same signal received by two different stations and the positions of these two stations define a hyperbolic curve.

What I'd wager is happening is something along the lines of the following. Lightning strikes over the ocean and emits a radio signal at c (speed of light). This travels however far with a dissipating amplitude and reaches multiple receivers in different locations. These receivers have an amplifier that increase the signal to a usable level, records the data of the radio signal and whatever else it picks up. All receivers that pick up the given lightning strike from over the ocean have their data compiled and used to triangulate the location of that strike using the hyperbolic method that I quoted above.