SWAP Pickup Ion Data Release (2022)

New Horizons’ Solar Wind Around Pluto (SWAP) instrument has been measuring interstellar hydrogen pickup ions (PUIs) out to ~52 au from the Sun. This data release provides the first high-time resolution observations of interstellar pickup ions (PUIs) in the outer heliosphere from ~49.5 – 52 au, including the first high-resolution observations of PUIs mediating shocks collected anywhere. These new data were enabled by a clever flight software reprogramming of the Solar Wind Around Pluto (SWAP) instrument on New Horizons to provide ~30-minute resolution compared to the prior ~24-hour time resolution. This time resolution is sufficient to resolve the shock structures and quantify the particle heating across these shocks. The new high-resolution observations are essential for understanding shocks in the outer heliosphere, the heliospheric termination shock, and more broadly for PUI mediated shocks across many astrophysical systems. A detailed description of the measurements, methodology, and analysis results can be found in McComas et al. (2022).

SWAP PUI distribution moments

SWAP count rates used to derive PUI distribution moments