Mars Surveyor '98 Lander . NASA Mars Lander . ... The Mars Surveyor '98 Lander is the companion spacecraft to the Mars Surveyor '98 Orbiter. The two spacecraft will be launched separately, but comprise a single mission to study the Martian weather, climate, and water and carbon dioxide budget. ... The lander consists of a base with three landing legs and an exposed upper deck to hold the instruments. Two solar power arrays extend from the deck parallel to the ground on opposite sides. ...