From: foxd_at_indiana.edu
Date: Sat Mar 05 2005 - 11:36:06 PST
Hi John,
Yes, I've recorded bursts of noise around the water hole frequencies during a
lightning storm. The thing is it is going to be wideband noise. Perhaps
looking for wideband pulses would be a better method to detect these.
73,
Daniel Fox
KF9ET
Quoting MarcusJohn_at_aol.com:
> I have here a citation from Geophysical Review Letters, 16 Jan 2005. It is
> at the bottom.
>
> One of my pet theories is that lightening on foreign worlds ought to be
> detectable.
>
> Now we have evidence that lightening emits xrays.
>
> I think it is possible that lightening emits in the water hole as well,
> since it seems
> to emit in a lot of different frequencies.
>
> If anyone would like to test my theory, then if they have a lightening storm
>
> within
> the line of sight, see if they can turn their Argus station towards the
> storm and
> see what the electronic signature of the storm is in the water hole.
>
> The storm has to be in the line of sight because these frequencies are not
> observable
> over the horizon.
>
> Please be careful. Turn the gain down at first, or take the LNA out of the
> circuit,
> and turn everything off if the storm
> is within 20 miles, so you don't get hit by the bolts.
>
> This obviously puts large constraints on the local topography of the Argus
> station.
> You cannot do this if you are deep in a valley because you cannot see 20
> miles
> to the horizon. Only Argus stations on a hill will be able to do this.
>
> Any comments? This might be an interesting project, and it may be
> publishable if we
> get good data.
>
> John.
>
> X-RAY THUNDERBOLT. Scientists have long suspected that lightning
> might generate x rays. However, until recently the observation of
> such x-rays has remained elusive, largely owing to the unpredictable
> nature of lightning. In the last few years a series of experiments
> by Joseph Dwyer and his colleagues at the Florida Institute of
> Technology and the University of Florida has shown that lightning
> indeed emits large bursts of x rays with energies up to about 250
> keV (about twice that of a chest x ray). These x rays are mostly
> produced not by the bright return strokes, but by the leaders that
> precede the stroke, as they propagate from the cloud to the ground.
> Now, Dwyer and his colleagues have discovered that these bursts of x
> rays are produced at the precise moment that the lightning steps
> forward along its jagged path. For unknown reasons, lightning does
> not travel to the ground in a continuous manner, but instead
> traverses the distance in a series of discrete steps. It is this
> stepping process that gives lightning its jagged, sometimes forked,
> appearance, and Dwyer has now shown that this same stepping process
> also makes x rays. The x rays are likely produced by strong
> electric fields that accelerate electrons to close to the speed
> of light. These so-called runaway electrons collide with air
> producing bremsstrahlung ("braking radiation" in German) x-rays.
> Dwyer says that higher energy gamma rays are also emitted sometimes,
> but that these seem to come from the thunderstorm cloud itself and
> not from the lightning stroke. (Dwyer et al., Geophysical Review
> Letters, 16 January 2005.)
>
>
This archive was generated by hypermail 2.1.6 : Sat Mar 05 2005 - 11:44:42 PST