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 26, 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 …

The Moon: Complete and live astronomy data, visibility information, sky charts, graphs, and tools for sky-watchers at all levels.

5 days ago · With our 2026 Moon Phase Calendar, you'll find the current Moon phase for tonight—plus, all the phases of the Moon for each day of the month.

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 …

Nov 19, 2021 · What Is the Umbra? The umbra is the dark center portion of a shadow. The Moon's umbra causes total solar eclipses, and the Earth's umbra is involved in total and partial …

A lunar phase or Moon phase is the apparent shape of the Moon 's day and night phases of the lunar day as viewed from afar. Because the Moon is tidally locked to Earth, the cycle of …

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 …

Sep 18, 2025 · The eight lunar phases are, in order: new Moon, waxing crescent, first quarter, waxing gibbous, full Moon, waning gibbous, third quarter, and waning crescent. The cycle …