TWINS and IBEX Observations of shock-associated Storms and Substorms

Abstract:

The Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) and Interstellar Boundary EXplorer (IBEX) missions provide a unique set of Energetic Neutral Atom (ENA) images of the magnetosphere. The TWINS mission has two spacecraft flown in Molniya orbits (inclination of 63.4, apogees of ~ 7.2 Re). Instruments aboard each spacecraft measure ENAs in the energy range from 1 to 100 keV / amu, and provide composition measurements for energies <~ 32 keV. The phasing of the two TWINS spacecraft allows for near continuous observations of the inner magnetosphere with high temporal (~ 1 min) and spatial (~0.1 Re) resolution. The IBEX mission is equipped with two sensitive ENA cameras designed to observe the interactions between our heliosphere and the interstellar medium. However, its vantage point from outside the magnetosphere (apogee ~ 40 Re in the ecliptic plane) also provides a unique 'outside in' view of the magnetosphere. IBEX images ENAs in the energy range of ~0.4 - 6 keV along a broad cut of the magnetosphere along the GSE-Z direction. The complementary ENA observations from TWINS and IBEX provide a global perspective of the dynamics of the magnetosphere. We present these observations of the global magnetospheric ENA response to shock-associated storms and substorms.