An orbiter to Neptune was considered as part of the aborted Mariner Mark II program in the 1990s, and several mission concepts for an orbiter were developed in the 2000s, including a concept by the California Institute of Technology and a version by the University of Idaho and Boeing, though none were selected for further development. Voyager 2 is the only space probe to have visited the Neptune system, completing a flyby on August 25, 1989. įurther information: Exploration of Neptune The mission concept was considered for possible recommendation as a mission priority in the 2023–2032 Planetary Science Decadal Survey, however for logistical reasons the Uranus Orbiter and Probe mission was selected as the ice giant obiter mission recommendation, with top priority ahead of the Enceladus Orbilander. The current proposal targets a launch in 2033 using the Space Launch System with arrival at Neptune in 2049, although trajectories using gravity assists at Jupiter have also been considered with launch dates in 2031.

The concept is being developed as a potential large strategic science mission for NASA by a team led by the Applied Physics Laboratory at Johns Hopkins University.

The orbiter would enter into a retrograde orbit of Neptune to facilitate simultaneous study of Triton and would launch an atmospheric probe to characterize Neptune's atmosphere. For these reasons and more, we advocate that an Ice Giant System explorer should become a strategic cornerstone mission within ESA’s Voyage 2050 programme, in partnership with international collaborators, and targeting launch opportunities in the early 2030s.Neptune Odyssey is an orbiter mission concept to study Neptune and its moons, particularly Triton. Exploring Uranus’ natural satellites and Neptune’s captured moon Triton could reveal how Ocean Worlds form and remain active, redefining the extent of the habitable zone in our Solar System. These two worlds are superb examples of how planets with shared origins can exhibit remarkably different evolutionary paths: Neptune as the archetype for Ice Giants, whereas Uranus may be atypical. This review article describes how such a mission could explore their origins, ice-rich interiors, dynamic atmospheres, unique magnetospheres, and myriad icy satellites, to address questions at the heart of modern planetary science.

We used this opportunity to review our present-day knowledge of the Uranus and Neptune systems, producing a revised and updated set of scientific questions and motivations for their exploration.

In 2019, the European Space Agency released a call for scientific themes for its strategic science planning process for the 2030s and 2040s, known as Voyage 2050. Ice Giants will be the last remaining class of Solar System planet to have a dedicated orbital explorer, and international efforts are under way to realise such an ambitious mission in the coming decades. Uranus and Neptune, and their diverse satellite and ring systems, represent the least explored environments of our Solar System, and yet may provide the archetype for the most common outcome of planetary formation throughout our galaxy.

Neptunes missions