Core Insights - A recent study by the American Association for the Advancement of Science indicates that precisely selecting the impact location on an asteroid can significantly enhance the effectiveness of defense missions, preventing asteroids from entering areas that could lead to future collisions, thereby ensuring long-term safety [1][2] Group 1: Research Background - The study is based on NASA's Double Asteroid Redirection Test (DART) mission executed in September 2022, which successfully demonstrated the "kinetic impactor" technique by impacting the satellite Dimorphos orbiting the asteroid Didymos [1] - The DART mission did not pose a new threat to Earth as the massive double asteroid system's orbit was not significantly altered [1] Group 2: Threat Assessment - For certain asteroids that directly orbit the Sun and may pose danger, even minor orbital changes can lead to the phenomenon of passing through gravitational keyholes, which can lock future collision paths [1][2] - Gravitational keyholes are specific regions in space where the gravitational influence of Earth or other planets can disturb an asteroid's orbit, potentially leading to future collisions [1] Group 3: New Technology Development - The research team developed a new technology to create "probability maps" of asteroid surfaces, indicating the likelihood of entering dangerous trajectories from various impact points [2] - This method utilizes data from the DART mission while considering individual differences such as shape, surface terrain, rotation state, and mass of each asteroid [2] Group 4: Analysis and Safety Measures - Ideally, parameters for the analysis can be obtained by sending a probe to rendezvous with the asteroid for high-resolution imaging and data collection; however, not all potential threats provide sufficient warning time for such missions [2] - The team asserts that even ground-based telescope observations can facilitate initial analyses [2] - By calculating subsequent trajectories under different impact scenarios and identifying the most dangerous evolutionary paths, scientists can determine the safest impact locations, ensuring long-term protection for Earth [2]