Uranus Pathfinder was a mission concept for the Uranian system evaluated in the 2010s by the European Space Agency. ^[1] In 2011, scientists from the Mullard Space Science Laboratory in the United Kingdom proposed the joint NASA–ESA Uranus Pathfinder mission to Uranus. It would have been a medium-class (M-class) mission to be launched in 2022, and was submitted to the ESA in December 2010 with the signatures of 120 scientists from around the globe. ESA caps the cost of M-class missions at €470 million. ^{[2] [3] [4]} Uranus Pathfinder was proposed in support of ESA's Cosmic Vision 2015–2025. ^[5] The mission study including several possible combinations of launch dates, trajectories, and flybys (gravity assists), including flybys of Earth, Venus, and of the planet Saturn. ^[6] Indeed, the study noted the velocity change requirements are only marginally higher than for typical missions to Saturn of this period. ^[7]

In the baseline concept, UP is an ESA–NASA bilateral mission and it would launch on an Atlas V 551 in January 2025 on a Venus–Earth–Earth interplanetary transfer to Uranus, reaching Uranus orbit in November 2037 after a cruise phase lasting 12.8 years.

It would orbit Uranus in a highly eccentric 45-day polar science orbit, with close periapsis distances to Uranus to make high-fidelity measurements of Uranus's gravitational and magnetic fields.

The scientific payload has a strong heritage in Europe and beyond and includes: a narrow-angle camera, visible/near-IR imaging spectrometer, thermal IR bolometer, radio science, magnetometer, radio and plasma wave detector, and plasma detector.

The mission would use the Earth communication stations at New Norcia ( X band), and Cebreros (X and K_a bands) during its long cruise to the Uranian system. ^[8]

Possible flyby/ gravity assist combinations studied: ^[9]

• VVE (Venus–Venus–Earth)
• VEE
• EVVE
• VEES (Venus–Earth–Earth–Saturn)
• VVEES

For power, the proposal suggests using a European radioisotope thermoelectric generator based on americium-241, with NASA's MMRTG and ASRG mentioned as possible backup options, which would provide more power. ^[10]

• Atmosphere of Uranus
• Exploration of Uranus
• Moons of Uranus

Uranus mission proposals

• MUSE
• Oceanus
• ODINUS
• Uranus orbiter and probe

• Uranus Pathfinder