Simultaneous optical and meteor head echo measurements using the Middle Atmosphere Alomar Radar System (MAARSY): Data collection and preliminary analysis

摘要: Abstract The initial results of a two year simultaneous optical-radar meteor campaign are described. Analysis 105 double-station optical meteors having plane sky intersection angles greater than 5° and trail lengths in excess 2 km also detected by the Middle Atmosphere Alomar Radar System (MAARSY) as head echoes was performed. These events show median deviation radiants between radar determinations 1.5°, with 1/3 radiant agreement to less one degree. MAARSY tends record average speeds roughly 0.5 km/s 1.3 km higher records, part due sensitivity compared instruments. More 98% all not system. Using this non-detection ratio known limiting cameras, we estimate that meteoroid detection mass is 10−9–10−10 kg (astronomical magnitudes +11 +12) appropriate from 30 60 km/s. There clear trend peak RCS for brighter 35 −30 dBsm. For similar magnitudes, echo cross-section larger at speeds. Brighter fixed heights have consistently, on average, values, accordance established scattering theory. However, our data ∝ v/2, much weaker normally assumed v3, consequence requiring be detectable optically. Most smooth variation height broadly following light production behavior. A significant minority large variations relative curve over common intervals, reflecting fragmentation or possibly differential ablation. No optically occurring main beam times when collecting went unrecorded MAARSY. Thus there does appear any scale bias detections (comparatively) dataset, even very low