Planet
Mercury
A day on Mercury lasts longer than its entire year.
Surface gravity 0.38× Earth
Mean radius 2,440 km
Mass 0.055× Earth
Length of day 175.9 Earth days
Length of year 88 Earth days
Avg. temperature 167 °C
Moons 0
Distance from Sun 0.39 AU
Mercury compared to Earth
Mercury has about 0.38× the radius of Earth and 0.055× its mass. Its surface gravity is 0.38 times Earth's — so a 70 kg person would weigh about 26.4 kg there.
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