Effect of tidal-heating on the rheology of Io

Abstract

Io exhibits widespread volcanism powered by tides raised by Jupiter. The distribution of volcanoes offers a window into the interior of the moon. The distribution shows more volcanism at the equator as well as peak volcanic output which is shifted by roughly 30-60 degrees to the east of the subjovian point [1]. Models of tidal dissipation that assume a spherically symmetric, solid Io cannot reproduce this shift [2]. More recently, it has been proposed that tidal dissipation in a magma ocean [3] or in a non-spherically symmetric, solid Io [4] can induce this lag. In this study, we explore the second option and show that solid-body dissipation can induce an eastward shift of the tidal dissipation pattern.