Alarge asteroid strike on the Moon could have negative consequences for the artificial satellites we now depend on. That being the case, a NASA-led team has looked into the options for preventing Asteroid 2024 YR4 from making such an impact in 2032. Contrary to the usual conclusions that asteroids should be diverted, not destroyed, they think this is a time for a Hollywood-approved demolition event.

When 2024 YR4 was discovered last December, it sparked headlines around the world, given the small possibility it would strike the Earth less than eight years later. As we learned more about its orbit, that chance rose to 3 percent before being downgraded. At an estimated 60 meters (200 feet) wide, this is no dinosaur-killer in size, nor probably speed, but it is large enough to do serious local damage if it struck a populated area, or unleash tsunamis in the ocean.

We now know the chance of a direct hit to Earth is essentially zero, but the chance of 2024 YR4 striking the Moon in seven years is currently 4 percent. While most people have been looking forward to the history-making once-in-5,000-years show we might all get if such an event were to occur, some spoilsports are crying “won’t somebody think of the satellites” and considering options.

An impact this large would inevitably throw up a lot of material, and with no atmosphere to constrain it, vast quantities of tiny particles would escape the low lunar gravity and spread widely. Some of this material would impact Earth’s atmosphere, creating a marvelous meteor shower lasting several days. Most of the rest would expand around the general vicinity of the Earth-Moon system, sometimes colliding later to slightly increase our ongoing meteor count. 

This all sounds great until you consider all the satellites that are vulnerable to being hit by material this size, including the JWST and the International Space Station. In a pre-print paper still undergoing peer review, a team led by Brent Barbee of NASA’s Goddard Space Flight Center has looked into what can be done to minimise the danger.