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 …

Dec 20, 2025 · 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 …

Dec 17, 2025 · The Earth and Moon are tidally locked. Their rotations are so in sync we only see one side of the Moon. Humans didn't see the lunar far side until a Soviet spacecraft flew past …

Dec 15, 2025 · Research shows a full moon can modestly affect sleep, but its influence on mental health is much less certain.

We see the full moon when the sun is directly behind us, illuminating a full hemisphere of the moon when it is directly in front of us.

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 …

Articles About Moon (68) The Moon Phases The Moon has four primary and four intermediate lunar phases during a lunar month. Here's all you need to know about each phase of the lunar …

Explore the current phase of the moon, its rise and set times, nightly motion across the sky, and discover lunar features with our interactive map. Stay informed about the celestial movements …

Dec 19, 2025 · In the U.S., the New Moon occurs tonight, Dec. 19, when the Moon is nearly invisible in the night sky, ending the waning crescent phase and beginning a new lunar cycle. …

1 day ago · NASA’s plans to launch astronauts to the moon in early 2026. The Artemis II mission is expected to carry a crew around the moon — though not to the lunar surface.