About Space
MERCURY
Mercury—the smallest planet in our solar system and closest to the Sun—is only slightly larger than Earth's Moon. Mercury is the fastest planet, zipping around the Sun every 88 Earth days.
THE THINGS NEED-TO-KNOW ABOUT MERCURY
1
SMALLEST
Mercury is the smallest planet in our solar system—only slightly larger than Earth's Moon.
2
INSIDER
It is the closest planet to the Sun at a distance of about 36 million miles (58 million kilometers) or 0.39 AU.
3
LONG DAYS, SHORT YEARS
One day on Mercury (the time it takes for Mercury to rotate or spin once with respect to the stars) takes 59 Earth days. One day-night cycle on Mercury takes 175.97 Earth days. Mercury makes a complete orbit around the Sun (a year in Mercury time) in just 88 Earth days.
4
ROUGH SURFACE
Mercury is a rocky planet, also known as a terrestrial planet. Mercury has a solid, cratered surface, much like the Earth's moon.
5
BIG SUN
Standing on Mercury's surface at its closest approach to the Sun, our star would appear more than three times larger than it does on Earth.
6
RINGLESS
There are no rings around Mercury.