For nearly 40 years, Uranus and its five largest moons have been dismissed as frozen and lifeless. This view was formed by humanity’s only close encounter with the Uranian system at the edge of our cosmic neighbourhood. Data sent back by Voyager 2 in 1986 indicated that the distant ice giant was sterile and inactive. But that probe had the misfortune of flying past Uranus just when a powerful solar storm hit, creating a distorted impression of its true nature. Far from the barren worlds previously assumed, a new analysis suggests that the celestial bodies could hold hidden oceans, and perhaps even the conditions necessary to support life.
This news should put rocket boosters on the $4bn plan by Nasa, the US space agency, for a mission to return to Uranus. The clock is ticking to make it there by 2050, just in time for its planetary equinox, when sunlight floods Uranus and its moons from pole to pole. Nasa wants to launch a mission by 2032 – a timeline that allows the spacecraft to use Jupiter’s massive gravity like a slingshot and shoot a probe out to Uranus in time for its seasonal transition.
