Space Plasma Seminar: Five Years of Stereo Magnetospheric Imaging by TWINS

Jerry Goldstein, SWRI

Tuesday, May 14, 2013, 3:30pm

Wilder 111

Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) is the first stereoscopic magnetospheric imaging mission. TWINS is a NASA Explorer Mission of Opportunity performing simultaneous energetic neutral atom (ENA) imaging from two widely-separated Molniya orbits on two different spacecraft, and providing nearly continuous coverage of ENA emissions from the magnetosphere. The ENA imagers observe energetic neutrals produced from global magnetospheric ion populations, over a broad energy range (1-100 keV/u) with high angular (4-degree-by-4-degree) and time (about 1-minute) resolution. Each TWINS spacecraft also carries a Lyman alpha geocoronal imager to monitor the cold exospheric hydrogen atoms that produce ENAs from ions via charge exchange. Complementing the imagers are detectors that measure the local charged particle environment around the spacecraft. During its first five years of science operations, TWINS science analysis has discovered new global properties of geospace plasmas and neutrals, fostered understanding of causal relationships, confirmed theories and predictions based on in situ data, and yielded key insights needed to improve geospace models. This seminar will highlight TWINS science results in the following topics: (1) Global ion distributions including pitch angle; (2) Low altitude precipitating ions; (3) Ion temperature and composition; (4) Neutral hydrogen exosphere density; (5) Global modeling of the ring current; (6) In situ particle data; and (7) Multi-mission studies involving TWINS.