The Solar Wind Around Pluto (SWAP) Instrument Aboard New Horizons

The Solar Wind Around Pluto (SWAP) instrument on New Horizons will measure the interaction between the solar wind and ions created by atmospheric loss from Pluto. These measurements provide a characterization of the total loss rate and allow us to examine the complex plasma interactions at Pluto for the first time. Constrained to fit within minimal resources, SWAP is optimized to make plasma-ion measurements at all rotation angles as the New Horizons spacecraft scans to image Pluto and Charon during the flyby. To meet these unique requirements, we combined a cylindrically symmetric retarding potential analyzer with small deflectors, a top-hat analyzer, and a redundant/coincidence detection scheme. This configuration allows for highly sensitive measurements and a controllable energy passband at all scan angles of the spacecraft.     

Cosmic ray investigation for the Voyager missions; energetic particle studies in the outer heliosphere—And beyond

A cosmic-ray detector system (CRS) has been developed for the Voyager mission which will measure the energy spectrum of electrons from 3–110 MeV and the energy spectra and elemental composition of all cosmic-ray nuclei from hydrogen through iron over an energy range from 1–500 MeV/nuc. Isotopes of hydrogen through sulfur will be resolved from 2–75 MeV/nuc. Studies with CRS data will provide information on the energy content, origin and acceleration process, life history, and dynamics of cosmic rays in the galaxy, and contribute to an understanding of the nucleosynthesis of elements in the cosmic-ray sources. Particular emphasis will be placed on low-energy phenomena that are expected to exist in interstellar space and are known to be present in the outer Solar System. This investigation will also add to our understanding of the transport of cosmic rays, Jovian electrons, and low-energy interplanetary particles over an extended region of interplanetary space. A major contribution to these areas of study will be the measurement of three-dimensional streaming patterns of nuclei from H through Fe and electrons over an extended energy range, with a precision that will allow determination of anisotropies down to 1%. The required combination of charge resolution, reliability and redundance has been achieved with systems consisting entirely of solid-state charged-particle detectors.Principal Investigator of the Voyager Cosmic Ray Experiment.     

Waves on the subsolar ionopause of venus

The subsolar ionopause of Venus is expected to be stable to both the Kelvin-Helmholtz and flute instabilities. However, magnetic profiles obtained in the subsolar region indicate that the surface of the ionopause contains large amplitude corrugations, perhaps incipient flux ropes. A possible mechanism for destabilizing the boundary is suggested by the observation that the ion density does not drop abruptly at the ionopause but continues to decrease smoothly into the magnetosheath.     

Lunar Exploration Neutron Detector for the NASA Lunar Reconnaissance Orbiter

The design of the Lunar Exploration Neutron Detector (LEND) experiment is presented, which was optimized to address several of the primary measurement requirements of NASA’s Lunar Reconnaissance Orbiter (LRO): high spatial resolution hydrogen mapping of the Moon’s upper-most surface, identification of putative deposits of appreciable near-surface water ice in the Moon’s polar cold traps, and characterization of the human-relevant space radiation environment in lunar orbit. A comprehensive program of LEND instrument physical calibrations is discussed and the baseline scenario of LEND observations from the primary LRO lunar orbit is presented. LEND data products will be useful for determining the next stages of the emerging global lunar exploration program, and they will facilitate the study of the physics of hydrogen implantation and diffusion in the regolith, test the presence of water ice deposits in lunar cold polar traps, and investigate the role of neutrons within the radiation environment of the shallow lunar surface.