# How to measure voltage differential across different altitudes

Imagine two points, one directly above the other ( Point A - 10,000 feet (PA) Point B - 20,000 feet (PB)

Imagine there's voltage potential between those two points

Q1: How could you measure the voltage between those to points? Q2: What if the points were at the same altitude, but 10 miles away from each other. How could you measure the voltage potential? (i.e. PA is in Ohio at 10k feet and PB is in Indiana at 20k feet altitude - ground distance between the two points is 10 miles) Q3: How could you determine if the potential was oscillating?

• What about the distance do you think makes this different than any other voltage measurement? Aug 18, 2020 at 18:14
• Be careful when writing "10m", I (and probably many people) read "ten meters", not "10 miles". Aug 19, 2020 at 7:45
• @CortAmmon the goal was to find techniques across great distances. One of the solutions using weather balloons probably requires FAA registration, something you wouldn't find if you're measuring a circuit in your basement. Additionally, my goal was to see if other people were working on a similar scale and would be interested in joining efforts. Aug 20, 2020 at 0:29
• @Jean-MariePrival thank you for the insight, I've updated the original post to avoid that problem Aug 20, 2020 at 0:30
• "techniques across great distances" -> ludicrously long cable + plus standard mid air plugs :-) Seriously, no idea how to exactly measure a potential between mid air points. Air to ground can be estimated to a few magnitudes when lightning strikes (no measuring instrument I know of could survive) a prepared lure, aka lightning rod, or by examination of fulgurites, but I am not an expert ...
– user20217
Aug 20, 2020 at 10:16