Exact boundary-crossing time during Solar Orbiter’s second Venus flyby

Identify the exact time and location of Solar Orbiter’s inbound transition into Venus’s plasma environment during its second flyby using magnetic field data, and reconcile this with concurrent upstream observations to pinpoint the boundary crossing unambiguously.

Background

For Solar Orbiter’s second Venus flyby, the inbound entry into Venus’s far-tail plasma environment is less evident in magnetic field data than in density data. The magnetic field shows a rotation near 23:37 UTC on 2021-08-08, but increased fluctuations are not as pronounced as in other flybys, leading to ambiguity in the exact crossing time.

Although the authors compare to BepiColombo measurements to argue for a spatial boundary crossing, they explicitly note that the magnetic field data alone do not reveal a clear boundary-crossing moment, and they assign a generous uncertainty window.