NASA is preparing to destroy an asteroid to save the moon
Asteroid 2024 YR4, discovered last year, originally had a 3% chance of colliding with Earth.
This risk has now been eliminated, but there remains a 4% chance that it will crash into the Moon in December 2032. According to Universe Today, NASA scientists and engineers have begun working on scenarios to prevent this event.
Although there is no permanent base on the Moon, the impact of a large asteroid could lead to the formation of a debris cloud that would significantly increase the number of micrometeorites that threaten satellites orbiting the Earth and even ISS crews.
There aretwo response options: deflect or destroy the asteroid. To deflect it is preferable, but requires accurate knowledge of the mass of the object, which can range from 51 to 711 million kg. A miscalculation could, on the contrary, send it straight towards Earth. To avoid this, an exploration mission may be needed by 2028. But it is extremely difficult to prepare and launch such an expedition in three years.
Engineers are considering using existing missions such as OSIRIS-APEX or even the Psyche probe. However, to do so, they would have to abandon their current science goals.
Because of these difficulties, a report on arXiv details a plan to destroy the asteroid.
The first option is a kinetic strike: aim a heavy projectile at the object to split it into pieces up to 10 metres. This method was tested in the DART mission, but in this case much more power would be needed.
The second option is nuclear. According to calculations, an explosion with a power of 1 megaton produced at a certain height from the surface of the asteroid (the so-called "high-altitude detonation"), is capable of destroying it regardless of its mass. Although such operations have not been carried out before, they are theoretically possible and technically feasible. The prototype is the Starfish Prime test in 1962.
The decision to use one method or another will depend not only on science, but also on politics. It is not yet known whether 2024 YR4 will hit the Moon, but by 2028 it will be clearer. And by then, humanity should be ready to make a decision - including launching a nuclear projectile into space.