A European Space Agency (ESA) spacecraft,  Hera, has begun its journey to examine the effects of NASA’s asteroid-deflection test, known as the Double Asteroid Redirection Test (DART), which took place in 2022. The craft launched from Cape Canaveral, Florida, at 10:52 AM local time (15:52 BST) on Monday. Hera's mission is to study the aftermath of NASA's effort to alter the course of an asteroid called Dimorphos, a moonlet orbiting the larger asteroid Didymos.

The mission is part of an international collaboration aimed at developing strategies to prevent potentially dangerous asteroids from colliding with Earth. While Dimorphos posed no threat to Earth, NASA's DART mission successfully shifted the asteroid's trajectory, marking the first real-world demonstration of planetary defense. Scientists say that DART changed the asteroid’s course by a few meters, proving that such an intervention is possible.

The Hera spacecraft is expected to reach Dimorphos, approximately seven million miles away, by December 2026. Once there, it will analyze the size and depth of the impact crater created by NASA’s probe, along with two cube-shaped mini-probes that will examine the asteroid's composition and mass.

According to ESA scientist Naomi Murdoch, this mission will provide crucial data on the physical properties of asteroids. “We need to understand what are the physical properties of these asteroids? What are they made of?” Murdoch explained, emphasizing the importance of such knowledge for future asteroid-deflection efforts.

While the likelihood of an extinction-level asteroid hitting Earth is low, the DART and Hera missions target asteroids between 100 to 200 meters wide, which are difficult to detect from Earth and can cause significant damage if they enter the planet's atmosphere. In 2013, for example, a house-sized asteroid exploded over Chelyabinsk, Russia, causing widespread damage and injuring over 1,600 people.

With the Hera mission, scientists aim to refine techniques that could one day help deflect asteroids and minimize potential destruction. Prof. Murdoch highlighted the significance of this project, stating, “The dinosaurs didn’t have a space program, but we do.”

However, despite the success of DART, experts caution that not all asteroids will be as easy to intercept. Spotting and deflecting hazardous asteroids will require further research and advancements in space defense technologies.