Radar observations of highly-transient meteor and related plasma phenomena at Jicamarca Radio Observatory

We describe a variety of MLT (Mesosphere, Lower Thermosphere) transient—microsecond through a few seconds—phenomena observed at the Jicamarca Radio Observatory (JRO) with a few additional examples from Arecibo Observatory (AO). The primary source of these transient events is the meteoroid flux. However, a significant fraction are likely electrodynamic in nature and include EEJ- (Equatorial ElectroJet) and 150 km echo-related phenomena. These results introduce new HARM (High Altitude Radar Meteor; B. Gao, and J. D. Mathews, Mon. Not. R. Astron. Soc., 446, 2015, pp. 3404–3415, doi: 10.1093/mnras/stu2176) events extending to ∼180 km altitude. Also given are examples of meteoroid fragmentation and flaring and detailed observations of Field-Aligned Irregularity (FAI) and RSTE (Range-Spread, Trail-Echo) development following meteoroid flares. New features of these observations include the simultaneous use of six-receiver interferometry (holography) for angle-of-arrival-ambiguity removal and a hybrid interferometry/compressed-sensing technique that yields unprecedented spatial and temporal resolution of transient events.