In-Situ Observation by the ERG (Arase) Spacecraft (image) University of Tokyo Share Print E-Mail Caption The ERG spacecraft observed chorus waves and scattered electrons in the magnetosphere, the origin of pulsation auroras. The scattered electrons precipitated into the atmosphere resulting in auroral illumination. Intermittent occurrence of chorus waves and associated electron scattering lead to auroral pulsation. Credit 2018 ERG science team. Usage Restrictions Related to the news release only. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.