The duration of the Mars Climate Orbiter's science mission will be one Martian year, or approximately two Earth years. In addtion to collecting data, the Orbiter will act as a relay station for five years, assisting in data transmission to and from the Mars Polar Lander, as well as the 2001 Lander mission.

Two instruments are aboard the Orbiter: the Pressure Modulator Infrared Radiometer (PMIRR), and the Mars Color Imager (MARCI). PMIRR will provide detailed information about the atmospheric temperatire on Mars, dust, water vapor, and clouds. It will also provide valuable information about the amount of carbon dioxide (CO₂) that is added and removed from the poles each Martian Year. MARCI is comprised of two cameras that will observe the behavior of the Martian atmosphere and interaction between the atmosphere and the surface of the planet.

The mission's projected end date is December 1, 2004. If this mission is successful, we will have been able to witness the atmospheric conditions on Mars through each of its seasons, and from this data, perhaps understand the past and future weather conditions on Mars.