This picture shows where Meridiani Planum is on Mars. Click on image for full size (111K JPEG) Windows to the Universe original artwork by Randy Russell using images courtesy NASA/JPL.

Meridiani Planum is the name of a plain on Mars. One of the Mars Exploration Rovers, named Opportunity, landed there.

Meridiani Planum is very flat. "Planum" means "plain". Meridiani Planum is near the equator on Mars. It is also near the Prime Meridian on Mars. The Prime Meridian is the place where the longitude is equal to zero. Mars has latitude and longitude, just like Earth. That's how people describe where a place on Mars is - by stating its latitude and longitude.

Scientists think that there might have been water at Meridiani Planum in the past. They think there is a mineral at Meridiani Planum that usually forms in water. That mineral is called hematite.

Meridiani Planum is just to the east of the great canyon on Mars, Valles Marineris. It is in between Mars' southern highlands and its northern plains.