Mercury

credit
solarsystem.nasa.gov

In mythology, Mercury is the son of Maya and Zeus.
Symbols associated with Mercury: caduceus (key), winged sandals, a helmet on the head that helps to keep in touch with Pluto. Mercury is the only God who can enter Pluto's underworld without punishment.
Following the law of transfer. Which says that - what is above is what is below and vice versa. And - a macro is similar to a microsom, the description of the God Mercury (if the mythology bears true information.) should coincide with the characteristics of the planet Mercury. Let me remind you that ancient civilizations observed the movement of the planets. But many facts about him are known only with the development of technological progress. Mercury is the first planet in our solar system. The smallest, in mythology, Mercury is an eternally young youth, he was also a "postman" between the Gods.
It is very fast (the right quality for transmitting messages and information) one year on Mercury lasts 88 days. Mercury does not move around its axis, so the sunlight heats the side turned towards it, and there is eternal heat, and on the other side there is "eternal" cold and "eternal" night.
Since the night is as dark as the underworld of Pluto, the night symbolizes a "little" death, like a dream, into which daytime creatures fall asleep at night, to be reborn in the morning in the light of a new day. The same can be said about winter, during this period all plants “fall asleep” or “die” so that in spring they will be reborn with stormy greenery, and animals that are characterized by hibernation fall asleep (bears, hedgehogs, ground squirrels, etc.)
Since Mercury symbolizes duality and contains equal halves of black matter and light, the description of God Mercury as God having access to both kingdoms is correct.