Shelter Island: NASA's Mars Exploration Rover Opportunity drove just 700 meters after finding the "Block Island" meteorite and spotted another! On October 1, 2009 it took this image of a meteorite that has been named "Shelter Island." The pitted rock is about 47 centimeters long. Image and caption by NASA. Enlarge.
Block Island: This is a picture of "Block Island," the largest meteorite yet to be found on Mars. It is about 60 centimeters across (about 2 feet) and is estimated to weigh about one-half ton. Analysis of its composition by Rover Opportunity's alpha particle X-ray spectrophotometer reveals that it is rich in iron and nickel - proof positive that it is an iron meteorite. This photo was taken by the navigation camera on NASA's Mars Exploration Rover Opportunity on July 28, 2009.
The Mars Rover drove right past the rock, but NASA researchers noticed it a few days later in an image that was taken and transmitted down to Earth. So they sent Opportunity back to check out the rock and touch it with its robotic arm for an analysis. Image and caption by NASA. Enlarge.
"Heat Shield Rock" is the first meteorite ever identified on the surface of another planet. It is a baseball-size iron-nickel meteorite discovered by NASA's Mars Exploration Rover Opportunity on January 6, 2005. Its composition and identity as a meteorite were confirmed by the Rover's spectrophotometer - it determined that "Heat Shield Rock" was composed of iron and nickel. The Meteoritical Society originally named it "Meridiani Planum" after the location where it was found - this is the traditional naming convention for meteorites found on Earth. However, the name "Heat Shield Rock" has become more popular. It received that name because it was discovered near the location where Opportunity discarded its heat shield. How long the meteorite has been on the surface of Mars is unknown, however, it shows very little sign of rusting or other alteration. Image and caption by NASA. Enlarge Image.