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Lightning-made Waves In Earth's Atmosphere Leak Into Space

Posted by Soulskill on from the great-now-the-fithp-will-find-us dept.

TheNextCorner sends this quote from NASA: "At any given moment about 2,000 thunderstorms roll over Earth, producing some 50 flashes of lightning every second. Each lightning burst creates electromagnetic waves that begin to circle around Earth, captured between Earth's surface and a boundary about 60 miles up. Some of the waves – if they have just the right wavelength – combine, increasing in strength, to create a repeating atmospheric heartbeat known as Schumann resonance. ... NASA's Vector Electric Field Instrument aboard the U.S. Air Force's Communications/Navigation Outage Forecast System satellite has detected Schumann resonance from space. This comes as a surprise, since current models of Schumann resonance predict these waves should be caged at lower altitude, between the ground and a layer of Earth's atmosphere called the ionosphere."

5 of 72 comments (clear)

  1. Leaking energy by RightwingNutjob · · Score: 4, Interesting

    Is this like other waveguide phenomena, where the first or second-order approximation says the energy vanishes exponentially within a fraction of a wavelength around the waveguide, but if you don't want your radar set (or microwave oven) to explode, you still need to invest heavily in ventilation and/or liquid cooling?

  2. Re:Makes no sense by Fluffeh · · Score: 4, Interesting

    Well, it's not so much the wind escaping the chamber, more along the lines of the sound making it out. The only thing "getting out" is electromagnetic waves - and to be honest, I am surprised that the atmosphere actually keeps most of them in. If you think about it, I guess is makes sense, given you can bounce radio signals off the atmosphere to get the signal past the horizon and such - but I was just surprised that electromagnetic waves from lightning get caught inside our atmosphere.

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  3. Class M Planet Discovery by Anonymous Coward · · Score: 5, Interesting

    I suppose Schumann resonance occur on similar planets as well, and should be detectable.

  4. Re:Makes no sense by Anonymous Coward · · Score: 4, Interesting

    Well, it's not so much the wind escaping the chamber, more along the lines of the sound making it out. The only thing "getting out" is electromagnetic waves - and to be honest, I am surprised that the atmosphere actually keeps most of them in. If you think about it, I guess is makes sense, given you can bounce radio signals off the atmosphere to get the signal past the horizon and such - but I was just surprised that electromagnetic waves from lightning get caught inside our atmosphere.

    You can hear them on your radio around 2-3mhz.

  5. The frequencies by IceFoot · · Score: 5, Interesting

    According to Wikipedia, the resonances occur at extremely low frequencies (ELF) around 7.83 (fundamental), 14.3, 20.8, 27.3 and 33.8 Hz. That's Hertz, not megaHertz. Now, how can we tune them in? I, for one, do not own a radio that can receive those frequencies.