Operating Earth missions actively make measurements and send raw data to operation centers that process the data and make them available for archive and distribution at Earth science data centers. Missions are designed to operate for a lifetime on orbit ranging from one to several years. This defines the primary operational phase of the mission.

Missions that are still functional at the end of their primary operational phase undergo a senior review process at NASA Headquarters. A Senior Review Panel is convened to evaluate the scientific performance of each mission and the continued relevance of each mission to the NASA Science Strategic Plan. Performance factors include scientific merit, national needs, the technical status of the mission, and budget efficiency. Missions that pass the senior review process may then be extended beyond their primary operational phase into an extended operational phase.

Senior Reviews for Earth Operating Missions:

The table below lists all operating Earth missions.