Space remains an environment filled with unknowns y potential dangers for our planet. One of the greatest fears of the scientific community is the impact of an asteroid against the Earth, an event that, although unlikely, could have devastating consequences. In order to prepare for such a scenario, NASA carried out the DART (Double Asteroid Redirection Test) mission, an ambitious experiment to test the technology of asteroid deflection, marking a milestone in the planetary defense.
On September 26, 2022, the DART probe impacted Dimorphos, a small moon of the asteroid Didymos, in what was the first real-life demonstration of the technique. kinetic impact. This experiment not only achieved alter the orbit of the asteroid, but also left a large amount of scientific data that could aid in future asteroid defense strategies. Let's take a detailed look at how the mission was executed, the results obtained, and the ongoing research.
What is the DART mission and why is it important?
DART was conceived as a test to evaluate the effectiveness of the kinetic impact technique, which consists of alter the trajectory of an asteroid by colliding a spacecraft with its surface. NASA designed this mission in collaboration with several space agencies, including the European Space Agency (ESA), which would later send the Hera mission to analyze the effects of the impact in detail.
The asteroid chosen for the test was Dimorphos, a small natural satellite of Didymos with a diameter of approximately 160 metersLocated about 11 million kilometers from Earth, this binary system represented a ideal scenario for the experiment without posing a danger to our planet. Through this deflection mission, scientists hope to gain valuable information about the possibility of deflecting other asteroids that could threaten Earth, something also being studied with the asteroid Bennu.
The impact of DART against Dimorphos
The key moment of the mission took place on September 26, 2022, when the DART probe collided with Dimorphos at a distance of speed of approximately 22.000 kilometers per hourImages captured by the DRACO camera onboard the spacecraft showed the asteroid growing larger and larger until the transmission suddenly stopped at the moment of impact.
The collision generated a huge ejection of material, forming a cloud of debris that was later analyzed by ground-based and space-based telescopes, such as the Hubble Space Telescope and the James Webb. This ejection had a significant impact on the Dimorphos orbit, reducing its orbital period by 32 minutes, far exceeding the initial expectation of just 73 seconds.
Scientific and technological implications
The success of the DART mission demonstrated that the technique of kinetic impact is a viable option for the planetary defenseAlthough Dimorphos posed no threat to Earth, the experiment served to test this strategy in a realistic environment. It also allowed for firsthand study of the asteroid's composition, its response to the impact, and the behavior of the resulting debris.
One of the most interesting findings was the presence of a cloud of rock fragments that was left floating around the asteroid. Subsequent observations have detected up to 37 rocks several meters in diameter which were detached after the impact, which has generated new studies on the collateral effects of this type of maneuvers.
The Hera mission: the next step in research
To analyse the consequences of the impact in detail, ESA launched the Hera mission in October 2024. This spacecraft is currently en route to Dimorphos and is expected to arrive in 2026. Hera will study the internal structure of the asteroid, the crater left by DART and the distribution of the ejected material, providing crucial data for future missions planetary defense.
In addition to studying Dimorphos' physical characteristics, Hera will also test new technologies. for autonomous navigation in low-gravity environments and will deploy two small cubesats to obtain close-up observations of the asteroid.
Could Dimorphos fragments reach Earth?
A recent study published in The Planetary Science Journal suggests that some fragments of the asteroid could enter the Earth orbit in the coming years. Although they are unlikely to pose a danger, scientists believe they could generate a meteor shower observable from our planet.
The analysis indicates that the detached particles move at speeds of up to 1,5 kilometers per second and could take between 7 and 13 years to reach Earth. However, due to their small size, they are likely to disintegrate in the atmosphere before impacting the surface.
The impact of DART against Dimorphos has marked a before and after in the planetary defense. Not only has it demonstrated that kinetic impact technology is viable, but it has also opened up new lines of research into the Dynamics of asteroids and their interactions with spacecraft. With the Hera mission underway and ongoing studies of the debris generated, the scientific community continues to gain valuable information that could be crucial in the future, if humanity ever needs to deflect a real asteroid that threatens Earth.