What are the limitations of grounding?

Question

Electronics

Good afternoon.
We all at one time laughed at the picture where the ground line leads to a flower pot (and I even saw this in reality once) - but I still did not find the answer to the question - how big does the pot need to be for this to work?
The opposite question - if we do build a lunar base, will ground loops work on the moon? Or is she too small for that?
What about Ceres? Phobos?
Actually, I didn’t find any theoretical justification, and professional electricians to whom I asked this question simply didn’t understand it - that’s why I’m asking it here.

Answer 1

if the pot is large enough to cover all working or galvanically connected systems, then there will be grounding, more precisely, some potential, which for the entire system used will be taken as "zero".
if not, then no.
the ISS body for all station systems is the "earth", although relative to other space bodies and the Earth itself, it can have a large potential difference.

Answer 2

How big does the pot need to be for this to work?

Dimensions are not important, the main thing is that it is electrically connected to the surface of the Earth. Oh, and don't forget to water more often.
The surface of the Earth between the transformer substation and, for example, a house is used as a "spare neutral wire". Those. the neutral wire is connected to a rather large metal peg driven into the ground. On both sides: from the side of the transformer substation and, for example, from the side of the house. Thus, the surface of our Mother Earth is used as an additional zero wire between the substation and the house, albeit having a large resistance relative to cables.
Why is it needed? Yes, so that when the neutral wire going to your house breaks, the phases from different entrances (there is more than 1 phase per house in Russia) do not meet through consumers on the neutral wire. For in a 3-phase network used in the CIS and many other places, only between phase and zero is ~ 220 volts. Between two phases - full ~ 380.

Answer 3

about the Moon - in the conditions of space vacuum and more than 200 ° temperature differences, the soil there is drier than in the Sahara, and will have an prohibitively large SPECIFIC ELECTRIC RESISTANCE (Ohm * m) - a parameter that determines the level of "electrical conductivity" of the soil as a conductor, that is, how it will be good to spread the electric current from the ground electrode in such an environment.
This is a measured value that depends on the composition of the soil, the size and density
of its particles, humidity and temperature, the concentration of soluble chemicals (salts, acid and alkaline residues)
in it www.zandz.ru/udelnoe_soprotivlenie_grunta.html
and a little about phases at home - https://pastebin.com/WtyQGWZw