Mercury is hard to see from Earth even though it sometimes looks brighter than any of the stars in the sky But Mercury is a planet not a star It appears bright because it comes closer to us than does any other planet except Venus and Mars Because it orbits so close to the sun we do not see Mercury against the dark background of the night sky Mercury is visible only during twilight hours either low in the east just before sunrise or low in the west just after sunset The early Romans named Mercury after the messenger of their gods because it appeared to move more quickly through the sky than did any of the other planets
