Diameter of Mercury
Written by Fraser Cain
Mercury compared to Earth. Image credit: NASA
The diameter of Mercury is 4,878 km.
Need some way to compare that to something more familiar? The diameter of Mercury is only 38% the diameter of Earth. In other words, you could put almost 3 Mercurys side to side to match the diameter of Earth.
In fact, there are two moons in the Solar System which actually have a larger diameter than Mercury. The largest moon in the Solar System is Jupiter's moon Ganymede, with a diameter of 5,268 km and the second largest moon is Saturn's moon Titan, with a diameter of 5,152 km.
The Earth's moon is only 3,474 km, so Mercury isn't much bigger.
We have written many stories about Mercury here on Universe Today. Here's an article about a side of Mercury never before seen by spacecraft, and how Mercury is actually less like the Moon than previously believed.
Want more information on Mercury? Here's a link to NASA's World Book on Mercury, and here's NASA's Solar System Exploration Guide to Mercury.
We have also recorded a whole episode of Astronomy Cast that's just about planet Mercury. Listen to it here, Episode 49: Mercury.
Filed under: Astronomy
