In the very early hours of Sept. 1 — just under two days since the 4:05 a.m. EDT launch of NASA’s Radiation Belt Storm Probes — the team at the RBSP Mission Operations Center (MOC) controlling spacecraft A at the Johns Hopkins Applied Physics Laboratory in Laurel, Md. was about to power up that spacecraft’s Relativistic Electron Proton Telescope (REPT-A), one of the instruments that comprise the Energetic Particle, Composition, and Thermal Plasma Suite (ECT).