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 …

2 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 …

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 …

Sep 7, 2023 · How big is the Moon? The Moon is Earth’s only permanent natural satellite, and it’s the fifth-largest satellite in our solar system. The Moon’s diameter is approximately 2,160 miles …

2 days ago · This, researchers hope, will help settle a long debate about whether the Moon's inner heart is solid or molten, and lead to a more accurate understanding of the Moon's history – …

1 day ago · Moon inner core discovery: A new study confirms the Moon has a solid metal inner core surrounded by a molten outer layer, reshaping our understanding of its geology and …

Jun 25, 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 …

Nov 5, 2025 · With our 2025 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.

2 days ago · Most effort hitherto had been devoted to understanding the movements of the Moon through space, but now astronomers began to focus their attention on the character of the …

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 …