Mars Polar Lander launched 1999

Mars Polar Lander

The Mars Polar Lander and the Mars Climate Orbiter were launched separately on January 3, 1999, to study the Martian weather, climate, water and carbon dioxide.  The Polar Lander was planned to touch down on the southern pole region near the CO2 icecap.  However, on December 3, the probe was jettisoned, and a planned communcation blackout started that would last until the probe landed.  This was the last NASA heard from the Polar Lander.  It is assumed it hit the Martian surface at a high rate of speed and disintegrated upon impact.

NASA loses communication with Mars Polar Lander 1999

Suspecting frozen water beneath the Martian landscape at the south pole, NASA sent the Mars Polar Lander to search for evidence of recent climate change and near-surface ground ice in the polar regions.

The Mars Polar Lander reached the Red Planet on December 3, 1999, and just prior to stage separation and atmospheric entry, signals from the spacecraft mysteriously stopped.  No explanation has been found as to the sudden cessation of communication.  It is assumed that the Mars Polar Lander has crashed onto the surface of Mars.  How many probes litter the surface of Mars now?