  The Galileo mission to Jupiter discovered magnetic signatures associated with
hidden sub-surface oceans at the moons Europa and Callisto using the phenomenon
of magnetic induction. These induced magnetic fields originate from
electrically conductive layers within the moons and are driven by Jupiter's
strong time-varying magnetic field. The ice giants and their moons are also
ideal laboratories for magnetic induction studies. Both Uranus and Neptune have
a strongly tilted magnetic axis with respect to their spin axis, creating a
dynamic and strongly variable magnetic field environment at the orbits of their
major moons. Although Voyager 2 visited the ice giants in the 1980s, it did not
pass close enough to any of the moons to detect magnetic induction signatures.
However, Voyager 2 revealed that some of these moons exhibit surface features
that hint at recent geologically activity, possibly associated with sub-surface
oceans. Future missions to the ice giants may therefore be capable of
discovering sub-surface oceans, thereby adding to the family of known ocean
worlds in our solar system. Here, we assess magnetic induction as a technique
for investigating sub-surface oceans within the major moons of Uranus.
Furthermore, we establish the ability to distinguish induction responses
created by different interior characteristics that tie into the induction
response: ocean thickness, conductivity, and depth, and ionospheric
conductance. The results reported here demonstrate the possibility of
single-pass ocean detection and constrained characterization within the moons
of Miranda, Ariel, and Umbriel, and provide guidance for magnetometer selection
and trajectory design for future missions to Uranus.
