The Romans knew of seven bright objects in the sky; The Sun, Moon, and 5 brightest planets. So they named them after their most important gods. Mercury having the fastest orbit they named it after their God Mercury. Mercury is the god of travelers and as myth states he has a winged hat and shoes that allows him to fly. Mercury is very comparable to the Greek God Hermes, both are considered the messengers of the gods. Mercury is the son of the God Jupiter