The Moon
From lighting up our skies to preserving evidence of our solar system’s historyEarth’s closest neighbor plays a pivotal role in the study of our planet and beyond.
OBSERVE THE MOON
Daily Moon Guide
NASA's interactive map for observing the Moonevery day of the year.
Next Total Lunar Eclipse
Dec 312028
Moon Composition & Structure
Like Earththe Moon consists of three main layers: a crusta mantleand a core.
Billions of years agothe Moon was a molten world. As it solidifiedthe heaviest materials (metals like iron) sank down into the Moon’s centerand the lighter materials (lower density rocks) rose towards the surface. The result is a structure a bit like a chocolate-dipped cherry – solid coremostly solid/partly liquid mantleand thin outer crust.
Does the Moon Have an Atmosphere?
Yesbut just barely.
In contrast to Earth’s thick layers of airthe Moon’s exosphere is a bit like the haze you get when you whack a dirty rug with a broom: it includes a sampling of particles knocked free by impact. But instead of a rugthese particles come from the lunar surface. Instead of flying through the airthey’re ejected into near-emptiness. And instead of a broomthe Moon is pummeled by space debris.
Lunar Craters
Earth's Moon is covered in craters.
Lunar craters tell us the history not only of the Moonbut of other worldstoo. On the Moonwhere there’s no liquid water or windevidence of our solar system's impact history has been preserved for billions of years.
Moon Phases
Earth's view of the half-sunlit Moon shifts throughout the month.
As our perspective changeswe observe a pattern known as lunar phases: new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarterand waning crescent.
How Did the Moon Form?
Earth’s Moon was born out of destruction.
There are several theories about our Moon’s formationbut almost all share this point in common. Our early solar system was the scene of violent smashups that could end in obliteration or newlarger objects. Those mashed-together objects make up the planetsmoonsasteroids and other solar system objects we know today.
Uncovering Lunar Water
There’s water on the Moon.
Ancient ice hidden deep in permanently shadowed craters. H20 molecules on the sunlit lunar surface. Humanity's search for water on the Moon began hundreds of years ago. Here's a brief history of discoveries leading up to the confirmation of its presence.
Artemis II Crew Image
Far Side of the Moon
The Moon's far side gets as much sunlight as its near side.
Like Earththe Moon has a day side and a night sidewhich change as the Moon spins through space. The Sun always illuminates half of the Moon while the other half remains dark.
The far side of the Moon was about 20% sunlit during the Artemis II crew's lunar flyby. Around the farthest point in their journeythe astronauts saw both the Moon and Earth in a waxing crescent phase.
Features
Moon Dust
We can learn a lot from studying Moon dust—andthe Moon's powdery surface presents challenges for human and robotic explorers.
Lunar Volcanism
The Moon does not have erupting volcanoes todaybut it was once flooded with flowing lava.
The Moon & Tides
As distant as the Moon may seemits gravitational pull plays a huge role in the formation of Earth's ocean tides.
Moon Phases 2026
This visualization shows the Moon's phase and libration at hourly intervals throughout 2026as viewed from the Northern Hemisphere.
About Moon Phases
EXPLORATION X Science
The Science of Artemis
The Moon is a 4.5-billion-year-old time capsulepristinely preserved by the cold vacuum of space.
Artemis II carried its crew farther from Earth and closer to the Moon than any human has been in over half a century. The astronauts on board were both scientists and subjects as they flew around the far side of the Moon and back.
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