Several current active radar programmes are dedicated to monitoring both background interplanetary influx and stream spatial densities and structure. There are some areas where valuable insight may be gained about the meteoric process and therefore improvements in our models of radar reflection mechanisms and related processes of the meteoric plasma. There are specific areas where programmes might be valuably directed.
Employing geometrical arrangements to select head echoes to gain information about meteoroid Earth-impacting trajectories needs input about the details of the plasma that surrounds the ablating meteoroid; its production and maintenance. The role of meteoroid fragmentation needs targeting; how structural characteristics of the grains affect the created ionization and the form of the echo: are radars seeing all types of meteoroids or are our samples biased: there is a need to better understand the nature of the fragmentation (gross or minor) if we want unbiased sampling of interplanetary dust. Measurements of ablation coefficients and its effect on meteoroid deceleration needs further examination to fix more firmly the pre-atmospheric orbital speeds of grains sampled by ground-based radars.
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