Reacción a "Reactions to the first controlled asteroid impact"

The study of nature and the universe has allowed us to advance enormously in our understanding of our environment, from the nanoscopic to the cosmological, and to establish a body of knowledge, of scientific culture, which has contributed to our progress and development as a species on our planet. But it has also allowed us to identify a series of risks and dangers that were unknown to us and went completely unnoticed. This has been the case, for example, with radioactivity, with the identification of the role of viruses or bacteria or, as in this case, with the discovery of the nearly 200 impact craters on our planet, those of the Moon and those of other planetary bodies in our solar system (Mercury, Mars, Europa, Ceres, Pluto, etc.). 

In parallel to the discovery of all these "impactgenic structures" in the geological record, it has also been discovered that they are due to the arrival on Earth of large objects, which have contributed to the modification of environments, to drastic climatic changes and even to the extinction of certain species. This, together with the detection of millions of asteroids that accompany us in the so-called Near Earth Space, forces us to pay attention to this type of catastrophic events, which may pose a danger to humanity, and to try to be prepared in the event that an object - mainly an asteroid - is at risk of collision with the Earth. 

It is in this context of planetary defence that NASA's DART mission, which has struck the Dimorphos asteroid to test whether the probe's collision with this object will succeed in deflecting it, even slightly, from its orbit, is framed. So far, there have been impact-related laboratory experiments, crater field studies and numerous computer simulations of scenarios representing different types of collisions. But this is the first time a mission has been conducted with the aim of deflecting the asteroid, not destroying it. 

DART's target was a binary system that lies about 11 million kilometres from Earth. This system consists of the asteroid Didymos - about 780 metres in diameter - and Dimorphos - about 160 metres in diameter - which orbits the former primary object. The spacecraft, which had a speed of 23 000 km/h, hit Dimorphos to change its orbit within the binary system. The effect of the collision will provide crucial information to better understand how the deflection occurs, if it occurs at all. Another artificial satellite, LICIACube, is tasked with capturing images of the collision, the resulting crater and the cloud of ejected material. 

We have witnessed a unique and fundamental astrophysical and astrogeological mission, which is of no danger to the Earth and of great importance for understanding how to act in the future should we find ourselves in a situation of risk and danger of asteroidal impact. 

A few years ago I was the Spanish representative in the IMPACT programme of the European Science Foundation and author and scientific director of the High Level Technical Report for the current Department of National Security of the Presidency of the Government on this type of collision. I wish we could have had the data that, if all goes well, this mission will provide us with. A project of scientific and social importance for the whole of humanity that will help us to be prepared and to specify how to defend ourselves in the event that we might be exposed to such a danger in the future.