Fishing for atmospheric electricity

[haversin]

Three microcuries of Am-241 were placed in a aluminum pie tin.



The pie tin was then suspended 2.7 meters in the air by a fishing pole. The pie tin was insulated from ground by the nylon fishing line. A wire connection was hung from the pie tin to the top terminal of a gold leaf electroscope. The outer case of the electroscope was connected to Earth ground.



The first reading was at 11:43 am MST and based on the gold leaf deflection, represents a voltage of about 100 volts giving a field strength of 37 volts per meter.



The next reading was at 1:10 pm MST and  represents a voltage of about 225 volts giving a field strength of 83 volts per meter. This was the highest reading I got. Strong winds made me stop the experiment.



These field values seen low and this might be due to my backyard being in a depression with the terrain sloping up on two sides. I might try doing this experiment in my front yard were the terrain slopes down on two sides. If the neighbors see this however they'll probably think I'm a nut job.

[John123]

Is this going to end in a massive spark lol?

[haversin]

I hope not!
In theory the electroscope should give some warning. But that's "in theory". I think lightning has a mind of it's own.

Update:
 I was thinking it would be nice to record to electroscope reading automatically without me having to go out to manually read and record them. Then it hit me, take a time lapse video of the electroscope! I have an old smartphone with a time lapse video app on it. The camera is lousy but it's good enough to read the electroscope. I'm making a trial run today.

[johnf]

Why not build a field mill --which has a nice voltage output to go directly to a scope or auduino or whatever

[haversin]

Made one about six years ago, I'm going make a separate post on it.