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NASA Pinpoints Lightning The Old-Fashioned Way

Posted by ryuzaki0 on from the tech-on-your-tab dept.

ke4roh writes: "As a child, I would watch a lightning flash and count the seconds until I heard the first clap of thunder. Get three kids counting in different places, and you could figure out where that cloud-to-ground strike was by coordinating their counts. That's the premise behind NASA's latest lightning detector, according to a press release. It uses a radio to detect the strike and four microphones spaced about 20 feet (7 m) apart. The neat part is its accuracy - about 15 feet (5 m) within a 1 mile (1.6 km) radius. The information should help them determine if lightning may have damaged sensitive launchpad equipment."

2 of 13 comments (clear)

  1. neat. by Hadlock · · Score: 2, Interesting

    neat. so i'm guessing these are directional microphones, in a semicircle, pointed twords the launch pad. sounds like you could build your own "lightning dectector" with an old 486, and a couple of ISA sound cards... just run a script waiting for an abnormality in the TV/FM tuner in the box, and then start recording... could be an interesting project.

    --
    moox. for a new generation.
  2. Why pick up audio when RF is available? by martyb · · Score: 2, Interesting

    I was pondering this very thing a few days ago when a lightning storm passed by. I turned on my AM radio and discovered there was quite a range of frequencies that would pick up when there was a flash of lightning. So, my thoughts were to use a number of AM radio receivers, arranged equidistant around a circle, each sending their signals to a processor located at the center of the circle.

    Now, it appears that the NASA folks are using microphones to pick up the sound of the thunder. Thunder is just the noise made by the lightning. Why not pick up the RF field, itself? I would think there would be less distortion and a clearer signal. Instead of 4 microphones, use 4 AM radios. Otherwise the technology would be the same in measuring the path differences (which was so clearly explained in the parent post).

    Now, I'm aware the RF signals can also experience distortion (multi-path, etc.) so I'm not claiming that AM receivers would be a panacea, but I would think that it would be more precise than anything that could be done with microphones.

    The preceding is based on what I'd learned in physics classes back in college... Is there anyone here who is more versed in RF signal processing who would care to comment?