Mercury is the first planet from the Sun and the smallest in the Solar System. It is a rocky planet with a trace atmosphere and a surface gravity slightly higher than that of Mars.

2 days ago · Mercury has long baffled astronomers because it defies much of what we know about planet formation. A new space mission arriving in 2026 might solve the mystery.

Nov 29, 2025 · Mercury, the innermost planet of the solar system and the eighth in size and mass. Its closeness to the Sun and its smallness make it the most elusive of the planets visible to the unaided …

May 7, 2025 · Explore a curated collection of resources about Mercury. These resources include activities that can be done at home, as well as videos and animations, images, and printable graphics.

Dec 24, 2025 · Mercury is the smallest planet in the Solar System in both mass and diameter. It’s 18 times less massive than the Earth, and its diameter barely reaches two-fifths of the Earth’s size.

Nov 13, 2025 · Mercury has been a cooled molten rock for billions of years, and it is the only planet in our Solar System that is bare rock. Planet Mercury is named after the Roman god Mercury because …

Mercury is the smallest planet in the Solar System and the closest one to the Sun. It's also a little-explored world, full of mystery, with a surface split into extremes and an interior that puzzles …

Jun 26, 2025 · Facts about the planet Mercury, including surface features, missions and the history of our relationship with the closest planet to the Sun.

Mar 27, 2025 · Mercury is the smallest planet in the solar system and the closest to the Sun. Mercury exhibits a grayish color, high density, and extreme temperature fluctuations between day and night.

Oct 19, 2018 · Named for the fleet-footed Roman messenger god, Mercury is the closest planet to the sun, zipping around our parent star at an average of 36 million miles away. However, Mercury’s orbit …