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 contiguous United States).

1 天前 · From lighting up our skies to preserving evidence of our solar system’s history, Earth’s closest neighbor plays a pivotal role in the study of our planet and beyond. The Moon makes Earth more livable by moderating our home planet's …

NASA's interactive map for observing the Moon each day of the year. WHAT WILL YOU SEE? This shows the Moon’s current phase in two ways: the percentage of the Moon’s nearside that …

2 天之前 · 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 Germanic and Old English derivation.

2025年1月30日 · As the Moon orbits Earth, different parts are in sunlight or darkness at different times. The changing illumination is why, from our perspective, the Moon goes through phases. During a "full moon," the hemisphere of the Moon we …

The brightest and largest object in our night sky, the Moon makes Earth a more livable planet by moderating our home planet's wobble on its axis, leading to a relatively stable climate. It also causes tides, creating a rhythm that has guided humans for thousands of years.

2025年3月25日 · Earth has just one moon – a rocky, cratered place, roughly a quarter the size of Earth and an average of 238,855 miles away. The Moon can be seen with the naked eye most nights as it traces its 27-day orbit around our planet.

2 天之前 · 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 repeats about once a month (every 29.5 days).

2004年7月16日 · 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 century ago. How did the moon form? Why...

The Moon is Earth's only natural satellite. We usually see it in the night sky but also during the day. Some other planets also have moons or natural satellites. Our moon is about one-fourth of the width of the Earth. [8] Because it is far away it looks small, about half a degree wide. The gravity on the moon is one-sixth of the Earth's gravity ...