Observations of Jupiter's distant magnetotail and wake

In the period from mid‐1980 to August 1981 the Voyager 2 plasma wave instrument occasionally detected clear signatures of Jovian nonthermal continuum radiation while the spacecraft was in the general downstream direction from Jupiter at distances of 5000 < R < 9000 R J (up to ∼4.5 AU). The magnitude and duration of the events increased as Voyager 2 approached the nominal aberrated tail position in the spring of 1981 and also indicated a periodicity suggesting some solar wind control. Each event shows characteristics suggestive of electromagnetic radiation trapped within a low‐density cavity. Supported with plasma observations, several of the events are characterized by a broad, moderately low density region surrounding a well‐defined, very low density core. We conclude that this series of continuum radiation events is best interpreted as the passage of Voyager 2 through the extended magnetotail and wake of Jupiter. Although the analysis of the events does not lead to a unique and unambiguous understanding of the structure of the tail, we can speculate on the various allowed tail configurations consistent with the observations. There are many cases in which there is a significant difference in the estimated duration of a given event as defined by the plasma wave or plasma observations, which may be explained by dynamical processes in the tail such as a pinch‐off or disconnection event similar to that observed in cometary plasma tails.