Scientists Propose Destruction of Asteroid Threatening Moon

Astronomers are closely monitoring the asteroid named 2024 YR4, which has gained attention due to its potential to collide with the Moon in 2032. Although earlier predictions regarding a direct impact with Earth have been ruled out, the asteroid still carries a 4% chance of striking the lunar surface. This possibility has raised concerns within the scientific community about the implications of such an event, particularly the risk of micrometeoroid debris entering low-Earth orbit, which could jeopardize the safety of astronauts aboard the International Space Station.

In a recent study conducted by researchers from NASA and several U.S. institutions, various strategies to mitigate this risk have been evaluated. The findings were submitted for peer review to the Journal of the Astronautical Sciences and are also available on the preprint server arXiv. The researchers concluded that the most effective approach may be to destroy the asteroid, rather than deflect it.

Evaluating the Deflection Strategy

While deflecting asteroid 2024 YR4 could theoretically prevent any impact, this strategy presents significant challenges. Successfully altering the asteroid’s trajectory would require precise calculations regarding its mass and density, which remain uncertain. Previous measurements from the James Webb Space Telescope indicated that the asteroid is approximately 60 meters in diameter, but its mass is estimated to fall between 33 million kilograms and over 930 million kilograms. This extensive range creates a substantial margin for error in determining the energy required for deflection.

NASA’s DART mission, which successfully altered the trajectory of the asteroid moonlet Dimorphos last year, demonstrated the feasibility of kinetic impactor techniques. However, the complexities involved in accurately deflecting 2024 YR4 within a limited timeframe make this method impractical. The researchers suggest that a reconnaissance mission to gather more data on the asteroid would be ideal, but the optimal launch window for such a mission would be in 2028, leaving only three years for development.

The Case for Destruction

In light of these difficulties, the researchers propose that destruction may be a more viable solution. One suggested method involves a robust kinetic disruption mission, similar to the DART mission but aimed at breaking the asteroid apart rather than nudging it off course. Unlike deflection, this approach has not been tested before, yet it offers a reasonable timeframe for development, with a launch window available from April 2030 to April 2032.

An alternative and more drastic option would be to use a nuclear device. This method would entail detonating a nuclear device on or near the asteroid, effectively fragmenting it into smaller pieces. While this has not been proven, the researchers assert that it is theoretically possible, with a launch window potentially available between late 2029 and late 2031.

Currently, there is still ample time before asteroid 2024 YR4 approaches the Moon, and it is expected to pass safely. Nevertheless, this situation presents a unique opportunity for scientists to refine their strategies for preventing impacts on both Earth and its natural satellite. Preparing for such contingencies ensures readiness should similar threats emerge in the future.