Pieces of Mercury may have been found on Earth, potentially allowing scientists to study the Solar System's innermost planet.

Mercury, the closest planet to the Sun, is a world of blazing heat, freezing nights, and endless mysteries. Recent photos ...

Most meteorites that have reached Earth come from the asteroid belt between Mars and Jupiter. But we have 1,000 or so ...

A meteor shower, a planet sighting, and a full moon. Here's how to see all of space's eye-catching activity in July.

Mercury, our solar system's innermost, unusually iron-rich planet. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington hide caption ...

Mercury will retrograde from Dec. 13 through Jan. 2 in the last of four times it appears to move backward in the sky this year. Every planet has in our solar system has retrograded for at least ...

Mercury is the closest planet to the sun and the smallest planet in our solar system.With a diameter of about 3,032 miles (4,880 kilometers), Mercury is less than half the size of Earth, which is ...

Mercury is also the smallest planet in the solar system, measuring just 3,032 miles wide at its equator. That makes it only slightly larger than Earth’s moon.

The planet Mercury is often cited as the most difficult of the five brightest naked-eye planets to see. Because it's the planet closest to the Sun, it never strays too far from the Sun's vicinity ...