If there is different timezones on the earth, then what about planets?

this is kinda a stner thought, but i was wondering, if there is different times depending on where you are on earth, then what about between 2 planets? can you be a day ahead of someone on earth if your on mars? and if your lightyears away from one another then are you eons apart in time??? which could explain aliens could exist and how they are advanced enough to have spacecraft on our planet :O cuz they are years ahead!