What drives the choice between orbiters, landers, and rovers?

Matching mission type to objectives

Mission design—orbiter, lander, or rover—is driven by the science goals, desired spatial coverage, and technical constraints. Each platform offers unique strengths.

When mission planners choose:

  • Orbiters provide global or regional context, remote sensing, and communications relay.
  • Landers deliver stationary, high-precision measurements at a single site.
  • Rovers enable mobility to explore diverse geology and perform targeted sampling.

Trade-offs to consider

  • Mobility vs. coverage: Rovers explore locally but orbiters see the whole planet.
  • Complexity and cost: Rovers are more complex and expensive than passive landers.
  • Science requirements: Some experiments need in situ sampling; others rely on spectral data from orbit.

A balanced exploration program uses all three platforms to build context, conduct detailed studies, and collect samples for future return.