In geophysical terms, the Moon is a planetary-mass object or satellite planet. Its mass is 1.2% that of the Earth, and its diameter is 3,474 km (2,159 mi), roughly one-quarter of Earth's (about as wide as the …

3 days ago · The Moon makes Earth more livable, sets the rhythm of ocean tides, and keeps a record of our solar system's history. Explore NASA lunar science here.

Jan 21, 2026 · Discover fascinating Moon facts—from its size and orbit to gravity, brightness, and temperature. Learn what makes Earth’s Moon truly unique.

• By measuring the ages of lunar rocks, we know that the moon is about 4.6 billion years old, or about the same age as Earth. • The distance between the Earth and its moon averages about...

What is the moon made of, and how did it form? Learn about the moon's violent origins, how its phases shaped the earliest calendars, and how humans first explored Earth's only natural satellite half a …

MOON - To the moon and beyond

The moon is the Earth's only natural satellite and the closest celestial object. Learn about the moon and some of the theories about the moon's origin.

6 days ago · Moon, Earth’s sole natural satellite and nearest celestial body. Known since prehistoric times, it is the brightest object in the sky after the Sun. Its name in English, like that of Earth, is of …

6 days ago · Moon phases reveal the passage of time in the night sky. Some nights when we look up at the moon, it is full and bright; sometimes it is just a sliver of silvery light. These changes in...

The Moon Returning humans to lunar missions Why the moon? The Moon is one of Earth's closest habitable neighbors and provides an opportunity to gain valuable experience for missions to Mars …