A NASA series of medium-sized spacecraft to explore the Solar System. They are larger, more expensive, and less frequent than members of the Discovery Program. The first of the series was New Horizons, launched in 2006, and the second was the Juno mission to Jupiter in 2011. Missions in the New Frontiers Program are intended to be launched every three years, on average.

https://newfrontiers.nasa.gov/missions/index.cfml Official New Frontiers program website.