there are 18 moons,
rotates for 58 days, 15 hours and 30 minutes on Earth,
It takes Mercury about 59 Earth days to spin once on its axis (the rotation period), and about 88 Earth days to complete one orbit about the Sun. However, the length of the day on Mercury (sunrise to sunrise) is 176 Earth days.
Mercury is the smallest planet in our solar system -- only slightly larger than the Earth'smoon. It is the closest planet to the sun at a distance of about 58 million km (36 million miles) or 0.39 AU
Mercury's diameter is 1,516 miles (2,440 km), mass:328.5E21 kg (0.055 Earth mass)
