The Potential Danger to Satellites due to Ejecta from a 2032 Lunar Impact by Asteroid 2024 YR4

TL;DR

A potential lunar impact by asteroid 2024 YR4 in 2032 could eject significant lunar material, creating debris that poses a long-term impact risk to satellites in near-Earth space, highlighting the need for broader planetary defense.

Contribution

This study estimates the ejecta volume and potential satellite impact risk from a lunar impact event caused by asteroid 2024 YR4, emphasizing the importance of planetary defense beyond Earth.

Findings

Up to 10^8 kg of lunar material could be ejected in a 2032 impact.

Ejecta could cause years of increased meteoroid impact exposure to satellites.

Planetary defense should include considerations for cis-lunar space risks.

Abstract

On 2032 December 22 the 60 m diameter asteroid 2024 YR4 has a 4% chance of impacting the Moon. Such an impact would release 6.5 MT TNT equivalent energy and produce a ~1 km diameter crater. We estimate that up to 10^8 kg of lunar material could be liberated in such an impact by exceeding lunar escape speed. Depending on the actual impact location on the Moon as much as 10% of this material may accrete to the Earth on timescales of a few days. The lunar ejecta-associated particle fluence at 0.1 - 10 mm sizes could produce upwards of years to of order a decade of equivalent background meteoroid impact exposure to satellites in near-Earth space late in 2032. Our results demonstrate that planetary defense considerations should be more broadly extended to cis-lunar space and not confined solely to near-Earth space.