Mercury

How long does mercury run

It takes 59 Earth days to make one day (or one full rotation) on Mercury. However, a year on Mercury goes by fast! Because it's the closest planet to the Sun, it doesn't take very long to go all the way around. It completes one revolution around the Sun in just 88 Earth days. Just like Earth, Mercury also rotates on its own axis, but much more slowly: one day-night cycle on Mercury takes the. . How long is a day on Mercury? Days on Mercury are very long because the planet rotates very slowly. When compared to Earth, it's significantly smaller, with a diameter just about 38% of Earth's.