Uranus - Exploration

Exploration

In 1986, NASA's Voyager 2 interplanetary probe encountered Uranus. This flyby remains the only investigation of the planet carried out from a short distance, and no other visits are currently planned. Launched in 1977, Voyager 2 made its closest approach to Uranus on January 24, 1986, coming within 81,500 kilometers of the planet's cloudtops, before continuing its journey to Neptune. Voyager 2 studied the structure and chemical composition of Uranus's atmosphere, including the planet's unique weather, caused by its axial tilt of 97.77°. It made the first detailed investigations of its five largest moons, and discovered 10 new moons. It examined all nine of the system's known rings and discovered two new ones. It also studied the magnetic field, its irregular structure, its tilt and its unique corkscrew magnetotail caused by Uranus's sideways orientation.

The possibility of sending the Cassini spacecraft to Uranus was evaluated during a mission extension planning phase in 2009. It would take about twenty years to get to the Uranian system after departing Saturn. A Uranus orbiter and probe was recommended by the 2013–2022 Planetary Science Decadal Survey published in 2011;the proposal envisages launch during 2020–2023 and a 13-year cruise to Uranus. A Uranus entry probe could use Pioneer Venus Multiprobe heritage and descend to 1–5 atmospheres. The ESA evaluated a "medium-class" mission called Uranus Pathfinder. A New Frontiers Uranus Orbiter has been evaluated and recommended in the study, The Case for a Uranus Orbiter. Such a mission is aided by the ease with which a relatively big mass can be sent to the system—over 1500 kg with an Atlas 521 and 12-year journey. For more concepts see Proposed Uranus missions.