Welcome to Wikipedia

6,502,118 articles in English

Today's featured picture

Topographic map of Mars

This is a high-resolution topographic map of the surface of Mars, colored according to elevation, based on research led by Maria Zuber and David Smith on data collected by the Mars Orbiter Laser Altimeter, an instrument on board the NASA space probe Mars Global Surveyor. North is at the top of the main map, accompanied by two insets for the northern and southern polar regions. Highlands (red and orange) dominate the southern hemisphere of Mars, while lowlands (blue) predominate in the north – a feature known as the Martian dichotomy. Notable large surface features visible on the map include Olympus Mons (the highest mountain on Mars) and the volcanoes of Tharsis in the west, the Valles Marineris to the east of Tharsis, and the Hellas basin in the southern hemisphere.

Map credit: NASA/JPL/USGS; edited by WolfmanSF

Other areas of Wikipedia

  • Community portal – The central hub for editors, with resources, links, tasks, and announcements.
  • Village pump – Forum for discussions about Wikipedia itself, including policies and technical issues.
  • Site news – Sources of news about Wikipedia and the broader Wikimedia movement.
  • Teahouse – Ask basic questions about using or editing Wikipedia.
  • Help desk – Ask questions about using or editing Wikipedia.
  • Reference desk – Ask research questions about encyclopedic topics.
  • Content portals – A unique way to navigate the encyclopedia.

Wikipedia's sister projects

Wikipedia is written by volunteer editors and hosted by the Wikimedia Foundation, a non-profit organization that also hosts a range of other volunteer projects:

Wikipedia languages