Plasma Pressures in the Heliosheath From Cassini ENA and Voyager 2 Measurements: Validation by the Voyager 2 Heliopause Crossing

We report ground truth, 28- to 3,500-keV in situ ion and 5.2- to 55-keV remotely sensed ENA measurements from Voyager 2/Low Energy Charged Particle detector and Cassini/Ion and Neutral Camera, respectively, that assess the components of the ion pressure in the heliosheath. In this process, we predict an interstellar neutral hydrogen density of similar to 0.12cm(-3) and an interstellar magnetic field strength of similar to 0.5-nT upstream of the heliopause in the direction of V2, that is, consistent with the measured magnetic field and neutral density measurements at Voyager 1 from August 2012, when the spacecraft entered interstellar space, to date. Further, this analysis results in an estimated heliopause crossing by V2 of similar to 119AU, as observed, suggesting that the parameters deduced from the pressure analysis are valid. The shape of the >5.2-keV ion energy spectra play a critical role toward determining the pressure balance and acceleration mechanisms inside the heliosheath.