Uranus orbiter and probe

A Uranus orbiter and probe is a mission proposal for study of the planet Uranus. It was recommended to NASA in 2011 by its Planetary Science Decadal Survey 2013–2022. A mission study was conducted which also considered a Neptune orbiter, however, for feasibility reasons Neptune was dropped in favor of Uranus. Two white papers on Uranus exploration were also submitted to the Decadal Survey. The survey listed the Uranus orbiter and probe as the third priority for a Flagship mission class after the MAX-C rover and the JEO component of the Europa Jupiter System Mission.

Although a chemical propulsion mission to Uranus is possible, solar electric propulsion (ion engine) is preferred because it allows a larger spacecraft mass. If funded, the proposed mission would launch in 2020–2023 with launch-windows of 21 days every year; travel time to Uranus with solar-electric propulsion would be 13 years, with one Earth flyby for gravity assist.

In early 2012, because of the FY2013 budget proposal, NASA Flagship-class planetary missions were put on hold. There is also a study that recommended a medium-class concept for the New Frontiers program to develop such an orbiter for Uranus.

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