The committee strongly believes that the New Frontiers Program is a valuable and vital part of NASA’s solar system exploration program. The committee’s philosophy was to provide NASA with sufficient options and to provide potential proposers with sufficient flexibility in their proposals to enable NASA to select a mission that can be done within the constraints of the New Frontiers Program, particularly the cost cap. The health of the New Frontiers Program was an overriding priority for the committee. New Frontiers has so far been successful in selecting missions that accomplish science that is not possible under the Discovery Program. These missions will make fundamental contributions to scientific understanding of the formation and evolution of the solar system.


To develop a list of candidate missions for the next New Frontiers Announcement of Opportunity, the Committee on New Opportunities in Solar System Exploration: An Evaluation of the New Frontiers Announcement of Opportunity considered the missions discussed in the decadal survey. The decadal survey recommended five mission candidates and ranked them according to priority:

  • Kuiper Belt Pluto Explorer,

  • South Pole-Aitken Basin Sample Return,

  • Jupiter Polar Orbiter with Probes,

  • Venus In Situ Explorer, and

  • Comet Surface Sample Return.

To date there have been two New Frontiers missions selected—the New Horizons mission to Pluto and the Kuiper Belt and the Juno mission to orbit Jupiter.

The decadal survey listed five additional missions that were not recommended for reasons of “mission sequencing, technological readiness, or budget.”2 These missions, listed in the following order in the decadal survey, were not ranked according to scientific priority:

  • Network Science,

  • Trojan/Centaur Reconnaissance,

  • Asteroid Rover/Sample Return,

  • Io Observer, and

  • Ganymede Observer.


The New Horizons mission to Pluto (Box 1.1) was approved during the decadal survey and was essentially “grandfathered” into the New Frontiers Program. Launched in early 2006, New Horizons conducted a successful Jupiter flyby in February 2007 en route to a Pluto flyby in 2015 and is to conduct another flyby of a Kuiper Belt object sometime later. The second New Frontiers mission, the Juno mission to Jupiter (Box 1.2), was selected in 2005 and originally scheduled for launch in 2009. The launch date was delayed due to cost-phasing problems at NASA, and this delay substantially increased the cost of the overall mission. Juno will now launch in 2011 for arrival at Jupiter in 2015.

Both New Horizons and Juno were the result of lengthy efforts that predated the New Frontiers Program itself. New Horizons benefited from nearly a decade of studies of Pluto missions. Juno resulted from three previously proposed Discovery-class missions. The committee was impressed by this fact and the lesson that successful proposals are the result of a lengthy process of study, refinement, competition, and scientific and technological advances. In order for the New Frontiers Program to remain healthy into the future, the committee encourages not


New Frontiers in the Solar System, p. 197.

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