Successful Recovery of an Observed Meteorite Fall Using Drones and Machine Learning

We report the first-time recovery of a fresh meteorite fall using a drone and a machine-learning algorithm. The fireball was observed on 2021 April 1 over Western Australia by the Desert Fireball Network, for which a fall area was calculated for the predicted surviving mass. A search team arrived on-site and surveyed 5.1 km2 area over a 4 day period. A convolutional neural network, trained on previously recovered meteorites with fusion crusts, processed the images on our field computer after each flight. Meteorite candidates identified by the algorithm were sorted by team members using two user interfaces to eliminate false positives. Surviving candidates were revisited with a smaller drone, and imaged in higher resolution, before being eliminated or finally being visited in person. The 70 g meteorite was recovered within 50 m of the calculated fall line, demonstrating the effectiveness of this methodology, which will facilitate the efficient collection of many more observed meteorite falls

The main asteroid belt: The primary source of debris on comet-like orbits

Jupiter-family comets (JFCs) contribute a significant amount of debris to near-Earth space. However, telescopic observations of these objects seem to suggest that they have short physical lifetimes. If this is true, the material generated will also be short-lived, but fireball observation networks still detect material on cometary orbits. This study examines centimeter-to-meter-scale sporadic meteoroids detected by the Desert Fireball Network from 2014 to 2020 originating from JFC-like orbits. Analyzing each event's dynamic history and physical characteristics, we confidently determined whether they originated from the main asteroid belt or the trans-Neptunian region. Our results indicate that <4% of sporadic meteoroids on JFC-like orbits are genetically cometary. This observation is statistically significant and shows that cometary material is too friable to survive in near-Earth space. Even when considering shower contributions, meteoroids on JFC-like orbits are primarily from the main belt. Thus, the presence of genuine cometary meteorites in terrestrial collections is highly unlikely