Meteoroid orbital element distributions at 1 AU deduced from the Harvard Radio Meteor Project observations

Abstract

The orbital element distributions of meteoroids detected during the Harvard Radio Meteor Project, 1968–69 Synoptic Year Program, have been reanalysed to remove selection effects associated with the radar observations. Corrections are made for the observing schedule, antenna beampatterns, the radio diffusion ceiling, speed dependence of ionization production, the flux enhancement due to the Earth’s gravity and the probability of encounter with the Earth. These render the eccentricity, aphelion distance, and inclination distributions for meteoroids larger than 10⁻⁴ g (radius ∼200 μm), with orbits that cross the ecliptic near 1 AU.