The Navigator Program is a long-term NASA project charged with over-seeing all missions related to the detection and characterization of Earth-like planets. It also seeks to further understand how galaxies, stars, and planets form. Navigator, with a 25-year time window, is essentially an umbrella program for more specific current and proposed projects which seek out Earth analogues and possible extraterrestrial life. The main components of Navigator include two ground-based and two space based missions.
On Earth:
And in space:
The Navigator Program is itself an element of even larger decades long project of NASA: the Origins Program, addressing the origins of the universe, astronomical bodies, and life.