Electrodynamics Observations with Numerous Satellites (EONS)

1. Electrodynamics Observations with Numerous Satellites (EONS) Science Objective: To determine when and how the upper atmosphere is driven from below, when and how it is driven from above Science Questions: What are the roles of the disturbance dynamo, tidal dynamos and magnetospheric penetration electric fields in determining the global electrodynamics at? How does the coupling between ion and neutrals affect the structure of the upper atmosphere? Associated RFAs: F2, F3, F4, H2, H3, H4, J1, J2, J4 Mission Implementation Description: 6 small-sats in 450 km circular orbits, final configuration separated by 2 hours LT 3-axis stabilized; eclipse operations 5 in-situ instruments (TRL-9), 1 remote sensing (TRL 7) Payload resources req’d (each sat.): 16kg, 40W, 12kbps Measurement Strategy:Three Mission Phases Phase 1: Pearls on a string - all 6 satellites are deposited into the same orbital plane at 600 km. Phase 2: Slowly phasing – sequential satellite drops to 450 km after certain months - space satellites out in LT Phase 3: Final configuration - Spread out equally in local time at the same altitude in 6 orbital planes • Enabling and Enhancing Technology Development: • Small satellite technology with 3-axis stabilization • Next generation GPS receivers • Optimized for small satellites • Capable of using Galileo constellation • Ion thrusters optimized for small satellites would enhance maneuverability/lifetime