巡天再启程 问道向苍穹——访中国科学院院士、中国行星探测工程首席科学家侯增谦

Core Viewpoint - China successfully launched the Tianwen-2 probe on May 29, 2023, to explore asteroid 2016HO3 and comet 311P, marking a significant step in planetary exploration and sample collection [2][16]. Group 1: Mission Overview - The Tianwen-2 mission consists of two phases: the first phase (2025-2027) involves flying to and sampling the near-Earth asteroid 2016HO3, which is considered a potential source of primordial solar system information [5][16]. - The second phase (2028-2035) will focus on observing the main-belt comet 311P, which has characteristics of both comets and asteroids, to study its volatile components and formation [5][16]. Group 2: Future Missions - The Tianwen-3 mission is planned for launch around 2028, with a goal to return samples from Mars by 2031, including surface and subsurface samples weighing no less than 500 grams [6][16]. - Tianwen-4 is scheduled for around 2030, focusing on orbiting Jupiter and its moon Europa to investigate their spatial and internal structures [6][17]. Group 3: Scientific Goals - The primary scientific objectives of Tianwen-3 include searching for signs of extraterrestrial life, understanding the evolution of Mars' habitable environment, and studying its geological structure [8][12]. - The mission aims to clarify the distribution and evolution of water on Mars, as well as the mechanisms of atmospheric escape, which are crucial for understanding planetary habitability [10][12]. Group 4: Importance of Landing Site - The selection of landing sites for the Tianwen-3 mission is critical for achieving its scientific goals, requiring precise identification of high-value scientific locations that also meet engineering feasibility [12][18]. - The research team is employing methods similar to "mineral prediction" on Earth to evaluate potential landing sites on Mars, considering geological evolution, ancient climate, and water activity [13][18]. Group 5: Broader Context of Planetary Exploration - The exploration of Mars and other celestial bodies is part of a broader strategy to understand planetary habitability and the potential for extraterrestrial life, which is a significant focus of global scientific efforts [8][19]. - Following the Tianwen series, China plans to continue advancing its planetary exploration initiatives, including missions to Venus and the icy moons of the outer solar system [19][20].