Year: 2026
Type: article
Abstract: The population of Earth-impacting meteoroids and their size-dependent orbital elements are key to understanding the origin of meteorites and informing planetary defense efforts. Outstanding questions include the role of collisions in depleting meteoroids on highly evolved orbits and the relative importance of delivery resonances. Those depend on size, with current dynamical models considering only asteroids larger than 10 m in diameter. Based on 1202 sporadic meteoroids observed by the Global Fireball Observatory, we created a debiased model of the near-Earth meteoroid population in the 10 g–150 kg size range (approximately 1 cm–0.5 m in diameter) as they dynamically evolved from the main asteroid belt onto Earth-crossing orbits. The observed impact population is best matched with a collisional half-life decreasing from 3 Myr for meteoroids of 0.6 kg (7 cm) or higher to 1 Myr below this size, extending to the model lower bound of 10 g. Placing our results in context with near-Earth object models for larger sizes, we find that the inner main belt continues to dominate feeding the small 1–10 m diameter population primarily via the ν 6 secular resonance and the 3:1J mean-motion resonance. We also evaluated the potential significance of physical processes other than collisions on Earth-impacting meteoroids, such as low-perihelion disruptions from thermal stresses.
Source: The Astronomical Journal
Authors: Sophie E. Deam, Hadrien A. R. Devillepoix, David Nesvorný, Patrick M. Shober, Eleanor K. Sansom, Jim Albers, Eric Anderson, Zouhair Benkhaldoun, Peter G. Brown, Luke Daly, George DiBattista, Hasnaa Chennaoui Aoudjehane, Christopher D. K. Herd, Tom Herring, Jonathan Horner, Peter Jenniskens, Derek C. Poulton, Martin D. Suttle, Anna Zappatini
Institutions: Curtin University, International Centre for Radio Astronomy Research, Southwest Research Institute, Johnson Space Center, Search for Extraterrestrial Intelligence, Cadi Ayyad University, University of Sharjah, Western University, The University of Sydney, University of Oxford, University of Glasgow, University of Hassan II Casablanca, University of Alberta, Western Nevada College, University of Southern Queensland, The Open University, University of Bern
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Aeronautics and Space Administration, Australian Government, Curtin University of Technology, Nuclear Safety and Security Commission, Canadian Space Agency, Natural Sciences and Engineering Research Council of Canada, Science and Technology Facilities Council, Australian Research Council
Awards: G1553938062, Making Habitable Worlds: The Formation and Evolution of Moons and Planets, The cosmic carbon observatory, The UK Fireball Alliance - building an all-sky UK meteor observatory, Understanding the Geologic Evolution of the Solar System through Meteorites and other Planetary Samples, The Global Fireball Observatory: Illuminating Solar System Origins, Exploring solar system origins with the Desert Fireball Network, G7507362318, UK leadership in extraterrestrial sample return, A global fireball observatory, Expanding the Foundation of Planetary Science, G814497173, G8457223931
OpenAlex ID: W7127343316