Year: 2026
Type: preprint
Abstract: Meteoroids are known to impact the Moon although the smallest size fraction is unconstrained due to the difficulty in observing faint impact flashes. Here we present observations of lunar impact flashes from NASA’s Artemis II crew during their lunar flyby on 7 April 2026 UTC. Five impact flashes were observed on the lunar farside during a total solar eclipse. These observations indicate meteoroids impacting the Moon with a lower limit of ~4.65 cm in diameter. The energy of each impact was equivalent to ~0.64 lbs of TNT and created a new lunar crater less than 1 meter in diameter. This information is used to supplement risk assessments for impact debris on lunar infrastructure which is critical as NASA plans to develop a sustained human presence on the lunar surface. Artemis II flew outside of any major annual meteoroid streams, and thus these observations place a lower bound on the impact flux at the lunar surface. With these observations, the Artemis II crew set a record for the smallest meteoroids ever optically observed to impact the Moon.
Source: Research Square
Authors: Jennifer Heldmann, William Cooke, Ernest Wright, Barbara Cohen, Jacob Richardson, Megan Borel, Amber Turner, Alexandra Constantinou, Cynthia Evans, David Hollibaugh-Baker, Ariel Deutsch, Anthony Colaprete, Debra Needham, Juliane Gross, Jose Hurtado, Maria Banks, Kiarre Dumes, Marie Henderson, Kelsey Young
Institutions: Ames Research Center, Goddard Space Flight Center, Marshall Space Flight Center, National Aeronautics and Space Administration, University of Maryland, Baltimore County, Johnson Space Center, Amentum (United States), Bay Area Environmental Research Institute, The University of Texas at El Paso
Language: English
Topic: Astro and Planetary Science
Subfield: Space and Planetary Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225337035