Open main menu

Wikipedia β

The Moon Portal

FullMoon2010.jpg

The Moon is Earth's only natural satellite and is the fifth largest satellite in the Solar System. It is the largest natural satellite in the Solar System relative to the size of its planet, a quarter the diameter of Earth and 1/81 its mass, and is the second densest satellite after Io. It is in synchronous rotation with Earth, always showing the same face; the near side is marked with dark volcanic maria among the bright ancient crustal highlands and prominent impact craters. It is the brightest object in the sky after the Sun, although its surface is actually very dark, with a similar reflectance to coal. Its prominence in the sky and its regular cycle of phases have since ancient times made the Moon an important cultural influence on language, the calendar, art and mythology. The Moon's gravitational influence produces the ocean tides and the minute lengthening of the day. The Moon's current orbital distance, about thirty times the diameter of the Earth, causes it to be the same size in the sky as the Sun—allowing the Moon to cover the Sun precisely in total solar eclipses.

Selected article

De gerlache shackleton sverdrup crater.jpg

Shackleton is an impact crater that lies at the south pole of the Moon. The peaks along the crater's rim are exposed to almost continual sunlight, while the interior is perpetually in shadow. The low-temperature interior of this crater functions as a cold trap that may capture and freeze volatiles shed during comet impacts on the Moon. Measurements by the Lunar Prospector spacecraft showed higher than normal amounts of hydrogen within the crater, which may indicate the presence of water ice. The crater is named after Ernest Shackleton, a noted Anglo-Irish explorer of the Antarctic.

Selected picture

Buzz Aldrin in his spacesuit during the Apollo 11 moonwalk.
Credit: NASA

Buzz Aldrin in his spacesuit during the Apollo 11 moonwalk.

Did you know?

Aerial photo of the Descartes Highlands with features and Apollo 16 mission traverses labeled.

Things to do

In the news

Wikinews Space portal
Read and edit Wikinews

Related portals

WikiProjects

Categories

Quality content

Topics

Moon-footer.jpg

Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

Wikibooks
Books

Commons
Media

Wikinews 
News

Wikiquote 
Quotations

Wikisource 
Texts

Wikiversity
Learning resources

Wikivoyage 
Travel guides

Wiktionary 
Definitions

Wikidata 
Database

Wikispecies 
Species

Purge server cache