En frôlant un astéroïde à 400 mètres, une sonde japonaise montre qu’un rocher spatial menaçant la Terre pourrait être dévié

On July 5, 2026, Japan’s Hayabusa2 probe made history by flying within 400 meters of the asteroid Torifune, setting a new world record for the closest approach ever achieved during such a mission. The Japanese Aerospace Exploration Agency (JAXA) announced the achievement, highlighting its significance in demonstrating how potentially hazardous space rocks could be deflected from Earth's path. This milestone was captured in imagery released by Jiji Press on July 6, with the footage showing Hayabusa2 gliding past Torifune at speeds exceeding 18,000 kilometers per hour. The probe, roughly the size of a refrigerator, came within 400 meters of the asteroid’s surface and 744 meters of its center, surpassing earlier estimates that had placed the distance at around 800 meters from the center. According to JAXA, this marks the closest proximity ever recorded in a spacecraft’s flyby of an Earth-crossing asteroid. A scientist from JAXA, Yuya Mimasu, noted that compared to other global space probes, Hayabusa2 has come closer than any before it to an asteroid, surpassing a previous record set by a Chinese probe which had flown within 770 meters of another asteroid’s surface. Following the successful maneuver, JAXA released rare images capturing Torifune’s unusual shape, resembling a snowman. These black-and-white photographs, taken through a telescope camera, revealed two rounded objects connected together, challenging prior assumptions that the asteroid had an elongated form. Scientists were surprised by these findings, as they had previously believed Torifune to have a more stretched appearance. The images offer valuable insights into the composition and structure of near-Earth asteroids, contributing to ongoing efforts to better understand potential threats to our planet. This latest mission follows a successful test conducted by NASA in 2022, during which a spacecraft intentionally impacted the asteroid Dimorphos to alter its orbit. That experiment demonstrated the feasibility of using kinetic impactors to change the trajectory of space rocks, a technique that could one day be used to prevent collisions with Earth. The current mission, involving collaboration between JAXA and the European Space Agency (ESA), aims to further develop such planetary defense strategies. Hayabusa2 was launched in 2014 and has already completed several milestones, including landing on the asteroid Ryugu and collecting samples from its surface. Those samples, returned to Earth in 2020, provided scientists with crucial data about the early solar system, offering glimpses into conditions billions of years ago. Now, after completing its Torifune mission, the probe is scheduled to attempt a “rendezvous” with another asteroid, designated 1998KY26, in 2031. This planned encounter will involve either flying alongside the rock or landing on its surface to gather detailed scientific data. The success of Hayabusa2’s recent flyby underscores Japan’s growing capabilities in deep-space exploration and planetary defense. As the threat of asteroid impacts remains a concern for planetary safety, missions like these provide critical knowledge that could one day help protect Earth from cosmic hazards. With future plans in place, Hayabusa2 continues to play a vital role in advancing humanity’s understanding of the universe and safeguarding our planet.